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Sample records for ls coupling scheme

  1. Electromagnetic transitions of heavy quarkonia in the boosted LS-coupling scheme

    International Nuclear Information System (INIS)

    Ishida, Shin; Morikawa, Akiyoshi; Oda, Masuho

    1998-01-01

    Radiative transitions among heavy quarkonium systems are investigated in a general framework of the boosted LS-coupling (BLS) scheme, where mesons are treated in a manifestly covariant way and conserved effective currents are explicitly given. As a result it is shown that our theory reproduces the qualitative features of experiments remarkably well, giving evidence for the validity of the BLS scheme. (author)

  2. Intermediate coupling collision strengths from LS coupled R-matrix elements

    International Nuclear Information System (INIS)

    Clark, R.E.H.

    1978-01-01

    Fine structure collision strength for transitions between two groups of states in intermediate coupling and with inclusion of configuration mixing are obtained from LS coupled reactance matrix elements (R-matrix elements) and a set of mixing coefficients. The LS coupled R-matrix elements are transformed to pair coupling using Wigner 6-j coefficients. From these pair coupled R-matrix elements together with a set of mixing coefficients, R-matrix elements are obtained which include the intermediate coupling and configuration mixing effects. Finally, from the latter R-matrix elements, collision strengths for fine structure transitions are computed (with inclusion of both intermediate coupling and configuration mixing). (Auth.)

  3. Dielectronic recombination of P5+ and Cl7+ in configuration-average, LS-coupling, and intermediate-coupling approximations

    International Nuclear Information System (INIS)

    Badnell, N.R.; Pindzola, M.S.

    1989-01-01

    We have calculated dielectronic recombination cross sections and rate coefficients for the Ne-like ions P 5+ and Cl 7+ in configuration-average, LS-coupling, and intermediate-coupling approximations. Autoionization into excited states reduces the cross sections and rate coefficients by substantial amounts in all three methods. There is only rough agreement between the configuration-average cross-section results and the corresponding intermediate-coupling results. There is good agreement, however, between the LS-coupling cross-section results and the corresponding intermediate-coupling results. The LS-coupling and intermediate-coupling rate coefficients agree to better than 5%, while the configuration-average rate coefficients are about 30% higher than the other two coupling methods. External electric field effects, as calculated in the configuration-average approximation, are found to be relatively small for the cross sections and completely negligible for the rate coefficients. Finally, the general formula of Burgess was found to overestimate the rate coefficients by roughly a factor of 5, mainly due to the neglect of autoionization into excited states

  4. Scalar correlator, Higgs decay into quarks, and scheme variations of the QCD coupling

    Energy Technology Data Exchange (ETDEWEB)

    Jamin, Matthias [IFAE, BIST,Campus UAB, 08193 Bellaterra (Barcelona) (Spain); ICREA,Pg. Lluís Companys 23, 08010 Barcelona (Spain); Miravitllas, Ramon [IFAE, BIST,Campus UAB, 08193 Bellaterra (Barcelona) (Spain)

    2016-10-12

    In this work, the perturbative QCD series of the scalar correlation function Ψ(s) is investigated. Besides /rm ImΨ(s), which is relevant for Higgs decay into quarks, two other physical correlators, Ψ{sup ″}(s) and D{sup L}(s), have been employed in QCD applications like quark mass determinations or hadronic τ decays. D{sup L}(s) suffers from large higher-order corrections and, by resorting to the large-β{sub 0} approximation, it is shown that this is related to a spurious renormalon ambiguity at u=1. Hence, this correlator should be avoided in phenomenological analyses. Moreover, it turns out advantageous to express the quark mass factor, introduced to make the scalar current renormalisation group invariant, in terms of the renormalisation invariant quark mass m̂{sub q}. To further study the behaviour of the perturbative expansion, we introduce a QCD coupling α̂{sub s}, whose running is explicitly renormalisation scheme independent. The scheme dependence of α̂{sub s} is parametrised by a single parameter C, being related to transformations of the QCD scale parameter Λ. It is demonstrated that appropriate choices of C lead to a substantial improvement in the behaviour of the perturbative series for Ψ{sup ″}(s) and /rm ImΨ(s).

  5. A threshold-based fixed predictor for JPEG-LS image compression

    Science.gov (United States)

    Deng, Lihua; Huang, Zhenghua; Yao, Shoukui

    2018-03-01

    In JPEG-LS, fixed predictor based on median edge detector (MED) only detect horizontal and vertical edges, and thus produces large prediction errors in the locality of diagonal edges. In this paper, we propose a threshold-based edge detection scheme for the fixed predictor. The proposed scheme can detect not only the horizontal and vertical edges, but also diagonal edges. For some certain thresholds, the proposed scheme can be simplified to other existing schemes. So, it can also be regarded as the integration of these existing schemes. For a suitable threshold, the accuracy of horizontal and vertical edges detection is higher than the existing median edge detection in JPEG-LS. Thus, the proposed fixed predictor outperforms the existing JPEG-LS predictors for all images tested, while the complexity of the overall algorithm is maintained at a similar level.

  6. Finite Element Simulation of Medium-Range Blast Loading Using LS-DYNA

    Directory of Open Access Journals (Sweden)

    Yuzhen Han

    2015-01-01

    Full Text Available This study investigated the Finite Element simulation of blast loading using LS-DYNA. The objective is to identify approaches to reduce the requirement of computation effort while maintaining reasonable accuracy, focusing on blast loading scheme, element size, and its relationship with scale of explosion. The study made use of the recently developed blast loading scheme in LS-DYNA, which removes the necessity to model the explosive in the numerical models but still maintains the advantages of nonlinear fluid-structure interaction. It was found that the blast loading technique could significantly reduce the computation effort. It was also found that the initial density of air in the numerical model could be purposely increased to partially compensate the error induced by the use of relatively large air elements. Using the numerical approach, free air blast above a scaled distance of 0.4 m/kg1/3 was properly simulated, and the fluid-structure interaction at the same location could be properly duplicated using proper Arbitrary Lagrangian Eulerian (ALE coupling scheme. The study also showed that centrifuge technique, which has been successfully employed in model tests to investigate the blast effects, may be used when simulating the effect of medium- to large-scale explosion at small scaled distance.

  7. Investigation of coupling scheme for neutronic and thermal-hydraulic codes

    International Nuclear Information System (INIS)

    Wang Guoli; Yu Jianfeng; Pen Muzhang; Zhang Yuman.

    1988-01-01

    Recently, a number of coupled neutronics/thermal-hydraulics codes have been used in reaction design and safty analysis, which have been obtained by coupling previous neutronic and thermal-hydraulic codes. The different coupling schemes affect computer time and accuracy of calculation results. Numberical experiments of several different coupling schemes and some heuristic results are described

  8. Investigation on the MOC with a linear source approximation scheme in three-dimensional assembly

    International Nuclear Information System (INIS)

    Zhu, Chenglin; Cao, Xinrong

    2014-01-01

    Method of characteristics (MOC) for solving neutron transport equation has already become one of the fundamental methods for lattice calculation of nuclear design code system. At present, MOC has three schemes to deal with the neutron source of the transport equation: the flat source approximation of the step characteristics (SC) scheme, the diamond difference (DD) scheme and the linear source (LS) characteristics scheme. The MOC for SC scheme and DD scheme need large storage space and long computing time when they are used to calculate large-scale three-dimensional neutron transport problems. In this paper, a LS scheme and its correction for negative source distribution were developed and added to DRAGON code. This new scheme was compared with the SC scheme and DD scheme which had been applied in this code. As an open source code, DRAGON could solve three-dimensional assembly with MOC method. Detailed calculation is conducted on two-dimensional VVER-1000 assembly under three schemes of MOC. The numerical results indicate that coarse mesh could be used in the LS scheme with the same accuracy. And the LS scheme applied in DRAGON is effective and expected results are achieved. Then three-dimensional cell problem and VVER-1000 assembly are calculated with LS scheme and SC scheme. The results show that less memory and shorter computational time are employed in LS scheme compared with SC scheme. It is concluded that by using LS scheme, DRAGON is able to calculate large-scale three-dimensional problems with less storage space and shorter computing time

  9. SO(2 ell + 1) contains ? contains SO/sub L/(3) in group chains for L-S coupling

    International Nuclear Information System (INIS)

    Wu, Z.Y.; Sun, C.P.; Zhang, L.; Li, B.F.

    1986-01-01

    Racah pointed out in his 1949 article that there exists a proper subgroup of SO(7) which properly contains SO/sub L/(3) in group chains for L-S coupling. This paper investigates whether such a proper subgroup exists for SO(2l + 1) which contains SO/sub L/(3) for an arbitrary l and concludes that this subgroup exists only for the case in which l is equal to 3. 4 references

  10. Improvements and validation of the linear surface characteristics scheme

    International Nuclear Information System (INIS)

    Santandrea, S.; Jaboulay, J.C.; Bellier, P.; Fevotte, F.; Golfier, H.

    2009-01-01

    In this paper we present the last improvements of the recently proposed linear surface (LS) characteristics scheme for unstructured meshes. First we introduce a new numerical tracking technique, specifically adapted to the LS method, which tailors transverse integration weights to take into account the geometrical discontinuities that appear along the pipe affected to every trajectory in classical characteristics schemes. Another development allows using the volumetric flux variation of the LS method to re-compute step-wise constant fluxes to be used in other parts of a computational scheme. This permits to take greater advantage of the higher precision of the LS method without necessarily conceiving specialized theories for all the modular functionalities of a spectral code such as APOLLO2. Moreover we present a multi-level domain decomposition method for solving the synthetic acceleration operator that is used to accelerate the free iterations for the LS method. We discuss all these new developments by illustrating some benchmarks results obtained with the LS method. This is done by detailed comparisons with Monte-Carlo calculations. In particular we show that the new method can be used not only as a reference tool, but also inside a suitable industrial calculation scheme

  11. Strong-coupling constant at three loops in momentum subtraction scheme

    International Nuclear Information System (INIS)

    Chetyrkin, K.G.; Russian Academy of Sciences, Moscow; Kniehl, B.A.; Steinhauser, M.

    2008-12-01

    In this paper we compute the three-loop corrections to the β function in a momentum subtraction (MOM) scheme with a massive quark. The calculation is performed in the background field formalism applying asymptotic expansions for small and large momenta. Special emphasis is devoted to the relation between the coupling constant in the MOM and MS schemes as well as their ability to describe the phenomenon of decoupling. It is demonstrated by an explicit comparison that the MS scheme can be consistently used to relate the values of the MOM-scheme strong-coupling constant in the energy regions higher and lower than the massive-quark production threshold. This procedure obviates the necessity to know the full mass dependence of the MOM β function and clearly demonstrates the equivalence of both schemes for the description of physics outside the threshold region. (orig.)

  12. Strong-coupling constant at three loops in momentum subtraction scheme

    Energy Technology Data Exchange (ETDEWEB)

    Chetyrkin, K.G. [Karlsruhe Univ. (T.H.), Karlsruhe Inst. of Technology (KIT) (Germany). Inst. fuer Theoretische Teilchenphysik]|[Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research; Kniehl, B.A. [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik; Steinhauser, M. [Karlsruhe Univ. (T.H.), Karlsruhe Inst. of Technology (KIT) (Germany). Inst. fuer Theoretische Teilchenphysik

    2008-12-15

    In this paper we compute the three-loop corrections to the {beta} function in a momentum subtraction (MOM) scheme with a massive quark. The calculation is performed in the background field formalism applying asymptotic expansions for small and large momenta. Special emphasis is devoted to the relation between the coupling constant in the MOM and MS schemes as well as their ability to describe the phenomenon of decoupling. It is demonstrated by an explicit comparison that the MS scheme can be consistently used to relate the values of the MOM-scheme strong-coupling constant in the energy regions higher and lower than the massive-quark production threshold. This procedure obviates the necessity to know the full mass dependence of the MOM {beta} function and clearly demonstrates the equivalence of both schemes for the description of physics outside the threshold region. (orig.)

  13. Linear source approximation scheme for method of characteristics

    International Nuclear Information System (INIS)

    Tang Chuntao

    2011-01-01

    Method of characteristics (MOC) for solving neutron transport equation based on unstructured mesh has already become one of the fundamental methods for lattice calculation of nuclear design code system. However, most of MOC codes are developed with flat source approximation called step characteristics (SC) scheme, which is another basic assumption for MOC. A linear source (LS) characteristics scheme and its corresponding modification for negative source distribution were proposed. The OECD/NEA C5G7-MOX 2D benchmark and a self-defined BWR mini-core problem were employed to validate the new LS module of PEACH code. Numerical results indicate that the proposed LS scheme employs less memory and computational time compared with SC scheme at the same accuracy. (authors)

  14. Scheme for quantum state manipulation in coupled cavities

    Science.gov (United States)

    Lin, Jin-Zhong

    By controlling the parameters of the system, the effective interaction between different atoms is achieved in different cavities. Based on the interaction, scheme to generate three-atom Greenberger-Horne-Zeilinger (GHZ) is proposed in coupled cavities. Spontaneous emission of excited states and decay of cavity modes can be suppressed efficiently. In addition, the scheme is robust against the variation of hopping rate between cavities.

  15. Description of a stable scheme for steady-state coupled Monte Carlo–thermal–hydraulic calculations

    International Nuclear Information System (INIS)

    Dufek, Jan; Eduard Hoogenboom, J.

    2014-01-01

    Highlights: • A stable coupling scheme for steady-state MC–TH calculations is described. • The coupling scheme is based on the stochastic approximation method. • The neutron flux (or power) distribution is relaxed using a variable step-size. - Abstract: We provide a detailed description of a numerically stable and efficient coupling scheme for steady-state Monte Carlo neutronic calculations with thermal–hydraulic feedback. While we have previously derived and published the stochastic approximation based method for coupling the Monte Carlo criticality and thermal–hydraulic calculations, its possible implementation has not been described in a step-by-step manner. As the simple description of the coupling scheme was repeatedly requested from us, we have decided to make it available via this note

  16. A coupling of empirical explosive blast loads to ALE air domains in LS-DYNA (registered)

    International Nuclear Information System (INIS)

    Slavik, Todd P

    2010-01-01

    A coupling method recently implemented in LS-DYNA (registered) allows empirical explosive blast loads to be applied to air domains treated with the multi-material arbitrary Lagrangian-Eulerian (ALE) formulation. Previously, when simulating structures subjected to blast loads, two methods of analysis were available: a purely Lagrangian approach or one involving the ALE and Lagrangian formulations coupled with a fluid-structure interaction (FSI) algorithm. In the former, air blast pressure is computed with empirical equations and directly applied to Lagrangian elements of the structure. In the latter approach, the explosive as well as the air are explicitly modeled and the blast wave propagating through the ALE air domain impinges on the Lagrangian structure through FSI. Since the purely Lagrangian approach avoids modeling the air between the explosive and structure, a significant computational cost savings can be realized - especially so when large standoff distances are considered. The shortcoming of the empirical blast equations is their inability to account for focusing or shadowing of the blast waves due to their interaction with structures which may intervene between the explosive and primary structure of interest. The new method presented here obviates modeling the explosive and air leading up the structure. Instead, only the air immediately surrounding the Lagrangian structures need be modeled with ALE, while effects of the far-field blast are applied to the outer face of that ALE air domain with the empirical blast equations; thus, focusing and shadowing effects can be accommodated yet computational costs are kept to a minimum. Comparison of the efficiency and accuracy of this new method with other approaches shows that the ability of LS-DYNA (registered) to model a variety of new blast scenarios has been greatly extended.

  17. Monotone difference schemes for weakly coupled elliptic and parabolic systems

    NARCIS (Netherlands)

    P. Matus (Piotr); F.J. Gaspar Lorenz (Franscisco); L. M. Hieu (Le Minh); V.T.K. Tuyen (Vo Thi Kim)

    2017-01-01

    textabstractThe present paper is devoted to the development of the theory of monotone difference schemes, approximating the so-called weakly coupled system of linear elliptic and quasilinear parabolic equations. Similarly to the scalar case, the canonical form of the vector-difference schemes is

  18. Approximation scheme for strongly coupled plasmas: Dynamical theory

    International Nuclear Information System (INIS)

    Golden, K.I.; Kalman, G.

    1979-01-01

    The authors present a self-consistent approximation scheme for the calculation of the dynamical polarizability α (k, ω) at long wavelengths in strongly coupled one-component plasmas. Development of the scheme is carried out in two stages. The first stage follows the earlier Golden-Kalman-Silevitch (GKS) velocity-average approximation approach, but goes much further in its application of the nonlinear fluctuation-dissipation theorem to dynamical calculations. The result is the simple expression for α (k, ω), αatsub GKSat(k, ω) 4 moment sum rule. In the second stage, the above dynamical expression is made self-consistent at long wavelengths by postulating that a decomposition of the quadratic polarizabilities in terms of linear ones, which prevails in the k → 0 limit for weak coupling, can be relied upon as a paradigm for arbitrary coupling. The result is a relatively simple quadratic integral equation for α. Its evaluation in the weak-coupling limit and its comparison with known exact results in that limit reveal that almost all important correlational and long-time effects are reproduced by our theory with very good numerical accuracy over the entire frequency range; the only significant defect of the approximation seems to be the absence of the ''dominant'' γ ln γ -1 (γ is the plasma parameter) contribution to Im α

  19. An analytical demonstration of coupling schemes between magnetohydrodynamic codes and eddy current codes

    International Nuclear Information System (INIS)

    Liu Yueqiang; Albanese, R.; Rubinacci, G.; Portone, A.; Villone, F.

    2008-01-01

    In order to model a magnetohydrodynamic (MHD) instability that strongly couples to external conducting structures (walls and/or coils) in a fusion device, it is often necessary to combine a MHD code solving for the plasma response, with an eddy current code computing the fields and currents of conductors. We present a rigorous proof of the coupling schemes between these two types of codes. One of the coupling schemes has been introduced and implemented in the CARMA code [R. Albanese, Y. Q. Liu, A. Portone, G. Rubinacci, and F. Villone, IEEE Trans. Magn. 44, 1654 (2008); A. Portone, F. Villone, Y. Q. Liu, R. Albanese, and G. Rubinacci, Plasma Phys. Controlled Fusion 50, 085004 (2008)] that couples the MHD code MARS-F[Y. Q. Liu, A. Bondeson, C. M. Fransson, B. Lennartson, and C. Breitholtz, Phys. Plasmas 7, 3681 (2000)] and the eddy current code CARIDDI[R. Albanese and G. Rubinacci, Adv. Imaging Electron Phys. 102, 1 (1998)]. While the coupling schemes are described for a general toroidal geometry, we give the analytical proof for a cylindrical plasma.

  20. Synchronization of linearly coupled unified chaotic systems based on linear balanced feedback scheme with constraints

    International Nuclear Information System (INIS)

    Chen, H.-H.; Chen, C.-S.; Lee, C.-I

    2009-01-01

    This paper investigates the synchronization of unidirectional and bidirectional coupled unified chaotic systems. A balanced coupling coefficient control method is presented for global asymptotic synchronization using the Lyapunov stability theorem and a minimum scheme with no constraints/constraints. By using the result of the above analysis, the balanced coupling coefficients are then designed to achieve the chaos synchronization of linearly coupled unified chaotic systems. The feasibility and effectiveness of the proposed chaos synchronization scheme are verified via numerical simulations.

  1. A new scheme for the running coupling constant in gauge theories using Wilson loops

    Energy Technology Data Exchange (ETDEWEB)

    Kurachi, Masafumi [Los Alamos National Laboratory; Bilgici, Erek [AUSTRIA; Flachi, Antonion [KYOTO UNIV; Itou, Etsuko [KOGAKUIN UNIV; David Lin, C J [NATIONAL CHIAO-TUNG UNIV; Matsufuru, Hideo [KEK; Ohki, Hiroshi [KYOTO UNIV; Onogi, Tetsuya [KYOTO UNIV; Yamazaki, Takeshi [UNIV OF TSUKUBA

    2009-01-01

    We propose a new renormalization scheme of the running coupling constant in general gauge theories defined by using the Wilson loops. The renormalized coupling constant is obtained from the Cretz ratio in lattice simulations and the corresponding perturbative coefficient at the leading order. The latter calculation is performed by adopting the zeta-function resummation techniques. We make a benchmark test of our scheme in quenched QCD with the plaquette gauge action. The running of the coupling constant is determined by applying the step scaling procedure. Using several methods to improve the statistical accuracy, we show that the running coupling constant can be determined in a wide range of energy scales with relatively small number of gauge configurations.

  2. Electromagnetically induced transparency and nonlinear pulse propagation in a combined tripod and Λ atom-light coupling scheme

    International Nuclear Information System (INIS)

    Hamedi, H R; Ruseckas, J; Juzeliūnas, G

    2017-01-01

    We consider propagation of a probe pulse in an atomic medium characterized by a combined tripod and Lambda (Λ) atom-light coupling scheme. The scheme involves three atomic ground states coupled to two excited states by five light fields. It is demonstrated that dark states can be formed for such an atom-light coupling. This is essential for formation of the electromagnetically induced transparency (EIT) and slow light. In the limiting cases the scheme reduces to conventional Λ- or N -type atom-light couplings providing the EIT or absorption, respectively. Thus, the atomic system can experience a transition from the EIT to the absorption by changing the amplitudes or phases of control lasers. Subsequently the scheme is employed to analyze the nonlinear pulse propagation using the coupled Maxwell–Bloch equations. It is shown that a generation of stable slow light optical solitons is possible in such a five-level combined tripod and Λ atomic system. (paper)

  3. Neutronics and thermal hydraulics coupling scheme for design improvement of liquid metal fast systems

    International Nuclear Information System (INIS)

    Sanchez-Espinoza, V.H.; Jaeger, W.; Travleev, A.; Monti, L.; Doern, R.

    2009-01-01

    Many advanced reactor concepts are nowadays under investigations within the Generation IV international initiative as well as in European research programs including subcritical and critical fast reactor systems cooled by liquid metal, gas and supercritical water. The Institute of Neutron Physics and Reactor Technology (INR) at the Forschungszentrum Karlsruhe GmbH is involved in different European projects like IP EUROTRANS, ELSY, ESFR. The main goal of these projects is, among others, to assess the technical feasibility of proposed concepts regarding safety, economics and transmutation requirements. In view of increased computer capabilities, improved computational schemes, where the neutronic and the thermal hydraulic solution is iteratively coupled, become practicable. The codes ERANOS2.1 and TRACE are being coupled to analyze fuel assembly or core designs of lead-cooled fast reactors (LFR). The neutronic solution obtained with the coupled system for a LFR fuel assembly was compared with the MCNP5 solution. It was shown that the coupled system is predicting physically sound results. The iterative coupling scheme was realized using Perlscripts and auxiliary Fortran programs to ensure that the mapping between the neutronic and the thermal hydraulic part is consistent. The coupled scheme is very flexible and appropriate for the neutron physical and thermal hydraulic investigation of fuel assemblies and of cores of lead cooled fast reactors. The developed methods and the obtained results will be presented and discussed. (author)

  4. Novel sensing and control schemes for a three-mirror coupled cavity

    International Nuclear Information System (INIS)

    Huttner, S H; Barr, B W; Plissi, M V; Taylor, J R; Sorazu, B; Strain, K A

    2007-01-01

    We present two options for length sensing and control of a three-mirror coupled cavity. The control of the first cavity uses amplitude or single sideband modulation and phase modulation in combination with a beat-frequency demodulation scheme, whereas the control scheme for the second cavity incorporates phase modulation and single demodulation. The theoretical and experimental performance is discussed as well as the relevance to a research programme to develop interferometric techniques for application in future interferometric gravitational wave detectors

  5. Stable explicit coupling of the Yee scheme with a linear current model in fluctuating magnetized plasmas

    International Nuclear Information System (INIS)

    Silva, Filipe da; Pinto, Martin Campos; Després, Bruno; Heuraux, Stéphane

    2015-01-01

    This work analyzes the stability of the Yee scheme for non-stationary Maxwell's equations coupled with a linear current model with density fluctuations. We show that the usual procedure may yield unstable scheme for physical situations that correspond to strongly magnetized plasmas in X-mode (TE) polarization. We propose to use first order clustered discretization of the vectorial product that gives back a stable coupling. We validate the schemes on some test cases representative of direct numerical simulations of X-mode in a magnetic fusion plasma including turbulence

  6. Frequency domain based LS channel estimation in OFDM based Power line communications

    OpenAIRE

    Bogdanović, Mario

    2015-01-01

    This paper is focused on low voltage power line communication (PLC) realization with an emphasis on channel estimation techniques. The Orthogonal Frequency Division Multiplexing (OFDM) scheme is preferred technology in PLC systems because of its effective combat with frequency selective fading properties of PLC channel. As the channel estimation is one of the crucial problems in OFDM based PLC system because of a problematic area of PLC signal attenuation and interference, the improved LS est...

  7. A tightly coupled scheme for neutronics and thermal–hydraulics using open-source software

    International Nuclear Information System (INIS)

    Wu, Hsingtzu; Rizwan-uddin

    2016-01-01

    Highlights: • A novel tight coupling scheme called “the Integrated Tight Coupling (ITC) method” is proposed. • The ITC method is implemented using DRAGON and OpenFOAM. • The ITC method is verified using a 1.5-D example. - Abstract: Coupling neutronic and thermal–hydraulic analyses of a nuclear reactor core is important because it helps identify the most relevant safety issues without conservative assumptions. Currently coupled computations solve the same governing equations using different coupling methods, which can be sorted into two categories: loose coupling and tight coupling. This paper proposes and verifies a third coupling approach called “the Integrated Tight Coupling (ITC) method”. The mathematical equations in the nuclear fuel are rearranged to be integrated via a novel concept of the energy-group function. In addition, the data from the neutron cross section library can be used directly. The ITC method is implemented using two open-source codes: the DRAGON code and OpenFOAM. Additionally, a coupled computation using these two codes is new and has not been done. The ITC method is verified using a 1.5-D (1-D neutronics and 2-D thermal–hydraulics) symmetric unit cell example. The mesh of the tightly integrated computation is 25% coarser than the loosely coupled one. Starting from a similar initial guess, the number of iterations for the ITC method is 24% fewer than that for the loosely coupled computation to reach the same accuracy. In addition, the ITC method is tested with different initial guesses. For all cases tested, the scheme converged to the same solution. With further improvement and additional testing, the ITC method has the potential to be incorporated with other neutronics and thermal–hydraulics codes.

  8. Forsskåls Fiskeherbarium

    DEFF Research Database (Denmark)

    Provencal, Philippe

    2017-01-01

    En beskrivelse af Peter Forsskåls fiskeherbarium og hans metoder i det marinbiologiske feltarbejde da han rejste i Egypten, Rødehavet og Yemen som ekspeditionsmedlem i den Arabiske Rejse 2061-67.......En beskrivelse af Peter Forsskåls fiskeherbarium og hans metoder i det marinbiologiske feltarbejde da han rejste i Egypten, Rødehavet og Yemen som ekspeditionsmedlem i den Arabiske Rejse 2061-67....

  9. Global Convergence of a Modified LS Method

    Directory of Open Access Journals (Sweden)

    Liu JinKui

    2012-01-01

    Full Text Available The LS method is one of the effective conjugate gradient methods in solving the unconstrained optimization problems. The paper presents a modified LS method on the basis of the famous LS method and proves the strong global convergence for the uniformly convex functions and the global convergence for general functions under the strong Wolfe line search. The numerical experiments show that the modified LS method is very effective in practice.

  10. Controlling a Conventional LS-pump based on Electrically Measured LS-pressure

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    As a result of the increasing use of sensors in mobile hydraulic equipment, the need for hydraulic pilot lines is decreasing, being replaced by electrical wiring and electrically controllable components. For controlling some of the existing hydraulic components there are, however, still a need...... this system, by either generating a copy of the LS-pressure, the LS-pressure being the output, or letting the output be the pump pressure. The focus of the current paper is on the controller design based on the first approach. Specifically a controlled leakage flow is used to avoid the need for a switching...

  11. Simulation of coupled flow and mechanical deformation using IMplicit Pressure-Displacement Explicit Saturation (IMPDES) scheme

    KAUST Repository

    El-Amin, Mohamed

    2012-01-01

    The problem of coupled structural deformation with two-phase flow in porous media is solved numerically using cellcentered finite difference (CCFD) method. In order to solve the system of governed partial differential equations, the implicit pressure explicit saturation (IMPES) scheme that governs flow equations is combined with the the implicit displacement scheme. The combined scheme may be called IMplicit Pressure-Displacement Explicit Saturation (IMPDES). The pressure distribution for each cell along the entire domain is given by the implicit difference equation. Also, the deformation equations are discretized implicitly. Using the obtained pressure, velocity is evaluated explicitly, while, using the upwind scheme, the saturation is obtained explicitly. Moreover, the stability analysis of the present scheme has been introduced and the stability condition is determined.

  12. A study on the modeling techniques using LS-INGRID

    Energy Technology Data Exchange (ETDEWEB)

    Ku, J. H.; Park, S. W

    2001-03-01

    For the development of radioactive material transport packages, the verification of structural safety of a package against the free drop impact accident should be carried out. The use of LS-DYNA, which is specially developed code for impact analysis, is essential for impact analysis of the package. LS-INGRID is a pre-processor for LS-DYNA with considerable capability to deal with complex geometries and allows for parametric modeling. LS-INGRID is most effective in combination with LS-DYNA code. Although the usage of LS-INGRID seems very difficult relative to many commercial mesh generators, the productivity of users performing parametric modeling tasks with LS-INGRID can be much higher in some cases. Therefore, LS-INGRID has to be used with LS-DYNA. This report presents basic explanations for the structure and commands, basic modelling examples and advanced modelling of LS-INGRID to use it for the impact analysis of various packages. The new users can build the complex model easily, through a study for the basic examples presented in this report from the modelling to the loading and constraint conditions.

  13. A Coupled Surface Nudging Scheme for use in Retrospective ...

    Science.gov (United States)

    A surface analysis nudging scheme coupling atmospheric and land surface thermodynamic parameters has been implemented into WRF v3.8 (latest version) for use with retrospective weather and climate simulations, as well as for applications in air quality, hydrology, and ecosystem modeling. This scheme is known as the flux-adjusting surface data assimilation system (FASDAS) developed by Alapaty et al. (2008). This scheme provides continuous adjustments for soil moisture and temperature (via indirect nudging) and for surface air temperature and water vapor mixing ratio (via direct nudging). The simultaneous application of indirect and direct nudging maintains greater consistency between the soil temperature–moisture and the atmospheric surface layer mass-field variables. The new method, FASDAS, consistently improved the accuracy of the model simulations at weather prediction scales for different horizontal grid resolutions, as well as for high resolution regional climate predictions. This new capability has been released in WRF Version 3.8 as option grid_sfdda = 2. This new capability increased the accuracy of atmospheric inputs for use air quality, hydrology, and ecosystem modeling research to improve the accuracy of respective end-point research outcome. IMPACT: A new method, FASDAS, was implemented into the WRF model to consistently improve the accuracy of the model simulations at weather prediction scales for different horizontal grid resolutions, as wel

  14. On the sub-model errors of a generalized one-way coupling scheme for linking models at different scales

    Science.gov (United States)

    Zeng, Jicai; Zha, Yuanyuan; Zhang, Yonggen; Shi, Liangsheng; Zhu, Yan; Yang, Jinzhong

    2017-11-01

    Multi-scale modeling of the localized groundwater flow problems in a large-scale aquifer has been extensively investigated under the context of cost-benefit controversy. An alternative is to couple the parent and child models with different spatial and temporal scales, which may result in non-trivial sub-model errors in the local areas of interest. Basically, such errors in the child models originate from the deficiency in the coupling methods, as well as from the inadequacy in the spatial and temporal discretizations of the parent and child models. In this study, we investigate the sub-model errors within a generalized one-way coupling scheme given its numerical stability and efficiency, which enables more flexibility in choosing sub-models. To couple the models at different scales, the head solution at parent scale is delivered downward onto the child boundary nodes by means of the spatial and temporal head interpolation approaches. The efficiency of the coupling model is improved either by refining the grid or time step size in the parent and child models, or by carefully locating the sub-model boundary nodes. The temporal truncation errors in the sub-models can be significantly reduced by the adaptive local time-stepping scheme. The generalized one-way coupling scheme is promising to handle the multi-scale groundwater flow problems with complex stresses and heterogeneity.

  15. A flexible coupling scheme for Monte Carlo and thermal-hydraulics codes

    Energy Technology Data Exchange (ETDEWEB)

    Hoogenboom, J. Eduard, E-mail: J.E.Hoogenboom@tudelft.nl [Delft University of Technology (Netherlands); Ivanov, Aleksandar; Sanchez, Victor, E-mail: Aleksandar.Ivanov@kit.edu, E-mail: Victor.Sanchez@kit.edu [Karlsruhe Institute of Technology, Institute of Neutron Physics and Reactor Technology, Eggenstein-Leopoldshafen (Germany); Diop, Cheikh, E-mail: Cheikh.Diop@cea.fr [CEA/DEN/DANS/DM2S/SERMA, Commissariat a l' Energie Atomique, Gif-sur-Yvette (France)

    2011-07-01

    A coupling scheme between a Monte Carlo code and a thermal-hydraulics code is being developed within the European NURISP project for comprehensive and validated reactor analysis. The scheme is flexible as it allows different Monte Carlo codes and different thermal-hydraulics codes to be used. At present the MCNP and TRIPOLI4 Monte Carlo codes can be used and the FLICA4 and SubChanFlow thermal-hydraulics codes. For all these codes only an original executable is necessary. A Python script drives the iterations between Monte Carlo and thermal-hydraulics calculations. It also calls a conversion program to merge a master input file for the Monte Carlo code with the appropriate temperature and coolant density data from the thermal-hydraulics calculation. Likewise it calls another conversion program to merge a master input file for the thermal-hydraulics code with the power distribution data from the Monte Carlo calculation. Special attention is given to the neutron cross section data for the various required temperatures in the Monte Carlo calculation. Results are shown for an infinite lattice of PWR fuel pin cells and a 3 x 3 fuel BWR pin cell cluster. Various possibilities for further improvement and optimization of the coupling system are discussed. (author)

  16. A flexible coupling scheme for Monte Carlo and thermal-hydraulics codes

    International Nuclear Information System (INIS)

    Hoogenboom, J. Eduard; Ivanov, Aleksandar; Sanchez, Victor; Diop, Cheikh

    2011-01-01

    A coupling scheme between a Monte Carlo code and a thermal-hydraulics code is being developed within the European NURISP project for comprehensive and validated reactor analysis. The scheme is flexible as it allows different Monte Carlo codes and different thermal-hydraulics codes to be used. At present the MCNP and TRIPOLI4 Monte Carlo codes can be used and the FLICA4 and SubChanFlow thermal-hydraulics codes. For all these codes only an original executable is necessary. A Python script drives the iterations between Monte Carlo and thermal-hydraulics calculations. It also calls a conversion program to merge a master input file for the Monte Carlo code with the appropriate temperature and coolant density data from the thermal-hydraulics calculation. Likewise it calls another conversion program to merge a master input file for the thermal-hydraulics code with the power distribution data from the Monte Carlo calculation. Special attention is given to the neutron cross section data for the various required temperatures in the Monte Carlo calculation. Results are shown for an infinite lattice of PWR fuel pin cells and a 3 x 3 fuel BWR pin cell cluster. Various possibilities for further improvement and optimization of the coupling system are discussed. (author)

  17. LCM-seq reveals the crucial role of LsSOC1 in heat-promoted bolting of lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Chen, Zijing; Zhao, Wensheng; Ge, Danfeng; Han, Yingyan; Ning, Kang; Luo, Chen; Wang, Shenglin; Liu, Renyi; Zhang, Xiaolan; Wang, Qian

    2018-05-17

    Lettuce (Lactuca sativa L.) is one of the most economically important vegetables. The floral transition in lettuce is accelerated under high temperatures, which can significantly decrease yields. However, the molecular mechanism underlying the floral tranition in lettuce is poorly known. Using laser capture microdissection coupled with RNA sequencing, we isolated shoot apical meristem cells from the bolting-sensitive lettuce line S39 at four critical stages of development. Subsequently, we screened specifically for the flowering-related gene LsSOC1 during the floral transition through comparative transcriptomic analysis. Molecular biology, developmental biology, and biochemical tools were combined to investigate the biological function of LsSOC1 in lettuce. LsSOC1 knockdown by RNA interference resulted in a significant delay in the timing of bolting and insensitivity to high temperature, which indicated that LsSOC1 functions as an activator during heat-promoted bolting in lettuce. We determined that two heat-shock transcription factors, HsfA1e and HsfA4c, bound to the promoter of LsSOC1 to confirm that LsSOC1 played an important role in heat-promoted bolting. This study indicates that LsSOC1 plays a crucial role in the heat-promoted bolting process in lettuce. Further investigation of LsSOC1 may be useful for clarification of the bolting mechanism in lettuce. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  18. Impact of filling scheme on beam induced RF heating in CERN LHC and HL-LHC

    CERN Document Server

    AUTHOR|(CDS)2241936; De Vito, Luca; Salvant, Benoit

    At CERN, after the first maintenance cycle (Long Shutdown 1, LS1) of the Large Hadron Collider (LHC), several sectors of the accelerator present a beam-induced heating much larger than expectations. This work compares data measured by cryogenic instrumentation with the expected heat load for various filling schemes and shows that impedance is not reasonably the major cause of the additional heat load. With this aim, the scaling of the power loss is analyzed carefully. In particular the scaling of the computed power loss from beam coupling impedance with the number of bunches is well understood only for a very broad band Impedance and for a very narrow band Impedance in ideal filling schemes that assume that the machine is full of equispaced bunches. This thesis analyzes also this dependence with number of bunches of the impedance of a resonator for a wide range of quality factors and more realistic filling schemes. The commonly assumed scaling with the square of number of bunches for narrow band resonator...

  19. Adaptive protection scheme

    Directory of Open Access Journals (Sweden)

    R. Sitharthan

    2016-09-01

    Full Text Available This paper aims at modelling an electronically coupled distributed energy resource with an adaptive protection scheme. The electronically coupled distributed energy resource is a microgrid framework formed by coupling the renewable energy source electronically. Further, the proposed adaptive protection scheme provides a suitable protection to the microgrid for various fault conditions irrespective of the operating mode of the microgrid: namely, grid connected mode and islanded mode. The outstanding aspect of the developed adaptive protection scheme is that it monitors the microgrid and instantly updates relay fault current according to the variations that occur in the system. The proposed adaptive protection scheme also employs auto reclosures, through which the proposed adaptive protection scheme recovers faster from the fault and thereby increases the consistency of the microgrid. The effectiveness of the proposed adaptive protection is studied through the time domain simulations carried out in the PSCAD⧹EMTDC software environment.

  20. An efficient coupled polynomial interpolation scheme for shear mode sandwich beam finite element

    Directory of Open Access Journals (Sweden)

    Litesh N. Sulbhewar

    Full Text Available An efficient piezoelectric sandwich beam finite element is presented here. It employs the coupled polynomial field interpolation scheme for field variables which incorporates electromechanical coupling at interpolation level itself; unlike conventional sandwich beam theory (SBT based formulations available in the literature. A variational formulation is used to derive the governing equations, which are used to establish the relationships between field variables. These relations lead to the coupled polynomial field descriptions of variables, unlike conventional SBT formulations which use assumed independent polynomials. The relative axial displacement is expressed only by coupled terms containing contributions from other mechanical and electrical variables, thus eliminating use of the transverse displacement derivative as a degree of freedom. A set of coupled shape function based on these polynomials has shown the improvement in the convergence characteristics of the SBT based formulation. This improvement in the performance is achieved with one nodal degree of freedom lesser than the conventional SBT formulations.

  1. Neutron calculation scheme for coupled reactors

    International Nuclear Information System (INIS)

    Porta, Jacques.

    1980-11-01

    The CABRI and PHEBUS cores are of the low enrichment rod type in which the fuel is made up of uranium oxide pellets encased in tubular cladding but the SCARABEE core has high enrichment plates, the fuel, an aluminium-uranium alloy (UAl) is metal, rolled into plate form. These three cores in well described rectangular geometry, receive in their centres the very heterogeneous cylindrical test loops (numerous containments of different kinds, large void spaces acting as lagging). After a detailed study of these three reactors, it is found that the search for a calculation scheme (common to the three projects) leads to the elimination of the scattering approximation in our calculations. It is therefore necessary to review the various existing models from a theoretical angle and then to select a particular method, according to the available data processing tools, a choice that will be dictated by the optimization of the parameters: cost in calculation time, difficulties (or ease) of use and accuracy achieved. A problem of experiment interpretation by calculation is dealt with in Chapter 3. The determination of the coupling by calculation is closely linked to the geometrical and energy modelization chosen. But from the experimental angle the determination of the coupling also gives rise to problems with respect to the interpretation of the experimental values obtained by thermal balance determinations, counting of the gamma emission of the fission products of fissile detectors and counting of lanthane 140 in the fuel fission products. The method of calculation is discussed as is the use made of detectors and the counting procedures. In chapter 4, it is not a local modelization that is discussed but an overall one in an original three dimensional calculation [fr

  2. Summary: after LS1

    International Nuclear Information System (INIS)

    Pojer, M.; Schmidt, R.

    2012-01-01

    After LS1 the energy will be about 6.5 TeV. The physics potential of LHC is determined by the integrated luminosity useful for the experiments and not only by the peak luminosity. The integrated luminosity is determined by the peak luminosity, the luminosity decay and the efficiency of operation (availability). In this session two of these parameters are addressed, the peak luminosity and the availability. In this paper peak luminosity is discussed through the performance potential of the injectors and through the global performance reach of LHC after LS1. LHC availability is tackled through the issues of the reliability of the magnet powering and of the beam system and of the occurrence of quenches

  3. Influence of Terraced area DEM Resolution on RUSLE LS Factor

    Science.gov (United States)

    Zhang, Hongming; Baartman, Jantiene E. M.; Yang, Xiaomei; Gai, Lingtong; Geissen, Viollette

    2017-04-01

    Topography has a large impact on the erosion of soil by water. Slope steepness and slope length are combined (the LS factor) in the universal soil-loss equation (USLE) and its revised version (RUSLE) for predicting soil erosion. The LS factor is usually extracted from a digital elevation model (DEM). The grid size of the DEM will thus influence the LS factor and the subsequent calculation of soil loss. Terracing is considered as a support practice factor (P) in the USLE/RUSLE equations, which is multiplied with the other USLE/RUSLE factors. However, as terraces change the slope length and steepness, they also affect the LS factor. The effect of DEM grid size on the LS factor has not been investigated for a terraced area. We obtained a high-resolution DEM by unmanned aerial vehicles (UAVs) photogrammetry, from which the slope steepness, slope length, and LS factor were extracted. The changes in these parameters at various DEM resolutions were then analysed. The DEM produced detailed LS-factor maps, particularly for low LS factors. High (small valleys, gullies, and terrace ridges) and low (flats and terrace fields) spatial frequencies were both sensitive to changes in resolution, so the areas of higher and lower slope steepness both decreased with increasing grid size. Average slope steepness decreased and average slope length increased with grid size. Slope length, however, had a larger effect than slope steepness on the LS factor as the grid size varied. The LS factor increased when the grid size increased from 0.5 to 30-m and increased significantly at grid sizes >5-m. The LS factor was increasingly overestimated as grid size decreased. The LS factor decreased from grid sizes of 30 to 100-m, because the details of the terraced terrain were gradually lost, but the factor was still overestimated.

  4. A faster numerical scheme for a coupled system modeling soil erosion and sediment transport

    Science.gov (United States)

    Le, M.-H.; Cordier, S.; Lucas, C.; Cerdan, O.

    2015-02-01

    Overland flow and soil erosion play an essential role in water quality and soil degradation. Such processes, involving the interactions between water flow and the bed sediment, are classically described by a well-established system coupling the shallow water equations and the Hairsine-Rose model. Numerical approximation of this coupled system requires advanced methods to preserve some important physical and mathematical properties; in particular, the steady states and the positivity of both water depth and sediment concentration. Recently, finite volume schemes based on Roe's solver have been proposed by Heng et al. (2009) and Kim et al. (2013) for one and two-dimensional problems. In their approach, an additional and artificial restriction on the time step is required to guarantee the positivity of sediment concentration. This artificial condition can lead the computation to be costly when dealing with very shallow flow and wet/dry fronts. The main result of this paper is to propose a new and faster scheme for which only the CFL condition of the shallow water equations is sufficient to preserve the positivity of sediment concentration. In addition, the numerical procedure of the erosion part can be used with any well-balanced and positivity preserving scheme of the shallow water equations. The proposed method is tested on classical benchmarks and also on a realistic configuration.

  5. LS1: exciting times ahead

    CERN Multimedia

    Caroline Duc

    2013-01-01

    As the first and last proton-lead run of 2013 draws to a close, the extensive upgrade and maintenance programme of the LHC's first long shutdown (LS1) is about to get under way.   The LHC has provided physicists with a huge quantity of data to analyse since the first physics run in 2009. Now it's time for the machine, along with CERN's other accelerators, to get a facelift. LS1 will start on 13 February 2013, but this doesn’t mean that life at the Laboratory will be any less rich and exciting. Although there will be no collisions for a period of almost two years, the whole CERN site will be a hive of activity, with large-scale work under way to modernise the infrastructure and prepare the LHC for operation at higher energy. "A whole series of renovation work will be carried out around the LHC during LS1,” explains Simon Baird, deputy head of the EN Department. "The key driver is of course the consolidation of the 10,170 high-curren...

  6. Quenching of the Gamow-Teller matrix element in closed LS-shell-plus-one nuclei

    International Nuclear Information System (INIS)

    Towner, I.S.

    1989-06-01

    It is evident that nuclear Gamow-Teller matrix elements determined from β-decay and charge-exchange reactions are significantly quenched compared to simple shell-model estimates based on one-body operators and free-nucleon coupling constants. Here we discuss the theoretical origins of this quenching giving examples from light nuclei near LS-closed shells, such as 16 0 and 40 Ca. (Author) 12 refs., 2 tabs

  7. Solution of problems with material nonlinearities with a coupled finite element/boundary element scheme using an iterative solver. Yucca Mountain Site Characterization Project

    International Nuclear Information System (INIS)

    Koteras, J.R.

    1996-01-01

    The prediction of stresses and displacements around tunnels buried deep within the earth is an important class of geomechanics problems. The material behavior immediately surrounding the tunnel is typically nonlinear. The surrounding mass, even if it is nonlinear, can usually be characterized by a simple linear elastic model. The finite element method is best suited for modeling nonlinear materials of limited volume, while the boundary element method is well suited for modeling large volumes of linear elastic material. A computational scheme that couples the finite element and boundary element methods would seem particularly useful for geomechanics problems. A variety of coupling schemes have been proposed, but they rely on direct solution methods. Direct solution techniques have large storage requirements that become cumbersome for large-scale three-dimensional problems. An alternative to direct solution methods is iterative solution techniques. A scheme has been developed for coupling the finite element and boundary element methods that uses an iterative solution method. This report shows that this coupling scheme is valid for problems where nonlinear material behavior occurs in the finite element region

  8. Travelling Wave Pulse Coupled Oscillator (TWPCO) Using a Self-Organizing Scheme for Energy-Efficient Wireless Sensor Networks.

    Science.gov (United States)

    Al-Mekhlafi, Zeyad Ghaleb; Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad

    2017-01-01

    Recently, Pulse Coupled Oscillator (PCO)-based travelling waves have attracted substantial attention by researchers in wireless sensor network (WSN) synchronization. Because WSNs are generally artificial occurrences that mimic natural phenomena, the PCO utilizes firefly synchronization of attracting mating partners for modelling the WSN. However, given that sensor nodes are unable to receive messages while transmitting data packets (due to deafness), the PCO model may not be efficient for sensor network modelling. To overcome this limitation, this paper proposed a new scheme called the Travelling Wave Pulse Coupled Oscillator (TWPCO). For this, the study used a self-organizing scheme for energy-efficient WSNs that adopted travelling wave biologically inspired network systems based on phase locking of the PCO model to counteract deafness. From the simulation, it was found that the proposed TWPCO scheme attained a steady state after a number of cycles. It also showed superior performance compared to other mechanisms, with a reduction in the total energy consumption of 25%. The results showed that the performance improved by 13% in terms of data gathering. Based on the results, the proposed scheme avoids the deafness that occurs in the transmit state in WSNs and increases the data collection throughout the transmission states in WSNs.

  9. Travelling Wave Pulse Coupled Oscillator (TWPCO) Using a Self-Organizing Scheme for Energy-Efficient Wireless Sensor Networks

    Science.gov (United States)

    Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad

    2017-01-01

    Recently, Pulse Coupled Oscillator (PCO)-based travelling waves have attracted substantial attention by researchers in wireless sensor network (WSN) synchronization. Because WSNs are generally artificial occurrences that mimic natural phenomena, the PCO utilizes firefly synchronization of attracting mating partners for modelling the WSN. However, given that sensor nodes are unable to receive messages while transmitting data packets (due to deafness), the PCO model may not be efficient for sensor network modelling. To overcome this limitation, this paper proposed a new scheme called the Travelling Wave Pulse Coupled Oscillator (TWPCO). For this, the study used a self-organizing scheme for energy-efficient WSNs that adopted travelling wave biologically inspired network systems based on phase locking of the PCO model to counteract deafness. From the simulation, it was found that the proposed TWPCO scheme attained a steady state after a number of cycles. It also showed superior performance compared to other mechanisms, with a reduction in the total energy consumption of 25%. The results showed that the performance improved by 13% in terms of data gathering. Based on the results, the proposed scheme avoids the deafness that occurs in the transmit state in WSNs and increases the data collection throughout the transmission states in WSNs. PMID:28056020

  10. Three-dimensional coupled Monte Carlo-discrete ordinates computational scheme for shielding calculations of large and complex nuclear facilities

    International Nuclear Information System (INIS)

    Chen, Y.; Fischer, U.

    2005-01-01

    Shielding calculations of advanced nuclear facilities such as accelerator based neutron sources or fusion devices of the tokamak type are complicated due to their complex geometries and their large dimensions, including bulk shields of several meters thickness. While the complexity of the geometry in the shielding calculation can be hardly handled by the discrete ordinates method, the deep penetration of radiation through bulk shields is a severe challenge for the Monte Carlo particle transport technique. This work proposes a dedicated computational scheme for coupled Monte Carlo-Discrete Ordinates transport calculations to handle this kind of shielding problems. The Monte Carlo technique is used to simulate the particle generation and transport in the target region with both complex geometry and reaction physics, and the discrete ordinates method is used to treat the deep penetration problem in the bulk shield. The coupling scheme has been implemented in a program system by loosely integrating the Monte Carlo transport code MCNP, the three-dimensional discrete ordinates code TORT and a newly developed coupling interface program for mapping process. Test calculations were performed with comparison to MCNP solutions. Satisfactory agreements were obtained between these two approaches. The program system has been chosen to treat the complicated shielding problem of the accelerator-based IFMIF neutron source. The successful application demonstrates that coupling scheme with the program system is a useful computational tool for the shielding analysis of complex and large nuclear facilities. (authors)

  11. A Coupled Surface Nudging Scheme for use in Retrospective Weather and Climate Simulations for Environmental Applications

    Science.gov (United States)

    A surface analysis nudging scheme coupling atmospheric and land surface thermodynamic parameters has been implemented into WRF v3.8 (latest version) for use with retrospective weather and climate simulations, as well as for applications in air quality, hydrology, and ecosystem mo...

  12. A mid-term report for LS1

    CERN Multimedia

    2014-01-01

    As the LHC’s first long shutdown, LS1, enters its second calendar year, it’s a good time for a mid-term report on how things are progressing.    Towards the end of last year, I had the pleasure to go down to the LHC tunnel to witness the closure of the first of the machine’s sectors to be completed. As I write, three sectors are now closed up, with a fourth not far behind. These are important milestones, and you can follow progress in detail in the regular LS1 reports in the Bulletin. They show that we’re on schedule for physics to resume in about a year from now, but more than that, they are an important reminder of the LS1 motto: safety, quality, schedule. It is fantastic news that we are on schedule, and testimony to the rigour that went into the detailed and complex planning of all the work that had to be undertaken in LS1. But more important than the schedule is the fact that we’ve carried out the work safely and that the qualit...

  13. Data on genome analysis of Bacillus velezensis LS69.

    Science.gov (United States)

    Liu, Guoqiang; Kong, Yingying; Fan, Yajing; Geng, Ce; Peng, Donghai; Sun, Ming

    2017-08-01

    The data presented in this article are related to the published entitled "Whole-genome sequencing of Bacillus velezensis LS69, a strain with a broad inhibitory spectrum against pathogenic bacteria" (Liu et al., 2017) [1]. Genome analysis revealed B. velezensis LS69 has a good potential for biocontrol and plant growth promotion. This article provides an extended analysis of the genetic islands, core genes and amylolysin loci of B. velezensis LS69.

  14. Data on genome analysis of Bacillus velezensis LS69

    OpenAIRE

    Liu, Guoqiang; Kong, Yingying; Fan, Yajing; Geng, Ce; Peng, Donghai; Sun, Ming

    2017-01-01

    The data presented in this article are related to the published entitled “Whole-genome sequencing of Bacillus velezensis LS69, a strain with a broad inhibitory spectrum against pathogenic bacteria” (Liu et al., 2017) [1]. Genome analysis revealed B. velezensis LS69 has a good potential for biocontrol and plant growth promotion. This article provides an extended analysis of the genetic islands, core genes and amylolysin loci of B. velezensis LS69.

  15. Robust LS-SVM-based adaptive constrained control for a class of uncertain nonlinear systems with time-varying predefined performance

    Science.gov (United States)

    Luo, Jianjun; Wei, Caisheng; Dai, Honghua; Yuan, Jianping

    2018-03-01

    This paper focuses on robust adaptive control for a class of uncertain nonlinear systems subject to input saturation and external disturbance with guaranteed predefined tracking performance. To reduce the limitations of classical predefined performance control method in the presence of unknown initial tracking errors, a novel predefined performance function with time-varying design parameters is first proposed. Then, aiming at reducing the complexity of nonlinear approximations, only two least-square-support-vector-machine-based (LS-SVM-based) approximators with two design parameters are required through norm form transformation of the original system. Further, a novel LS-SVM-based adaptive constrained control scheme is developed under the time-vary predefined performance using backstepping technique. Wherein, to avoid the tedious analysis and repeated differentiations of virtual control laws in the backstepping technique, a simple and robust finite-time-convergent differentiator is devised to only extract its first-order derivative at each step in the presence of external disturbance. In this sense, the inherent demerit of backstepping technique-;explosion of terms; brought by the recursive virtual controller design is conquered. Moreover, an auxiliary system is designed to compensate the control saturation. Finally, three groups of numerical simulations are employed to validate the effectiveness of the newly developed differentiator and the proposed adaptive constrained control scheme.

  16. Data on genome analysis of Bacillus velezensis LS69

    Directory of Open Access Journals (Sweden)

    Guoqiang Liu

    2017-08-01

    Full Text Available The data presented in this article are related to the published entitled “Whole-genome sequencing of Bacillus velezensis LS69, a strain with a broad inhibitory spectrum against pathogenic bacteria” (Liu et al., 2017 [1]. Genome analysis revealed B. velezensis LS69 has a good potential for biocontrol and plant growth promotion. This article provides an extended analysis of the genetic islands, core genes and amylolysin loci of B. velezensis LS69.

  17. Design and control strategy applying the novel highly effective magnetic flux coupling (HEMFC) scheme for a non-contact power transfer system

    International Nuclear Information System (INIS)

    Chen, W.-P.; Huang, W.-N.; Chen, P.-S.; Fan, T.-Y.; Chen, M.-P.; Teng, C.-C.

    2006-01-01

    In this paper, the novel design concept for highly effective magnetic flux coupling (HEMFC) schemes, based on enhancement of path guiding effect for leakage flux transmitting, is proposed for a non-contact power transfer system. Two implementation techniques are presented herein utilizing simple structure opinions of specific slant air gap as well as adding of metal bushing components. Both simulation and experimental results demonstrate that the improvement of magnetic coupling ratio and overall system efficiency are achieved by applying the two HEMFC schemes as the power transmitting devices

  18. Transition among synchronous schemes in coupled nonidentical multiple time delay systems

    International Nuclear Information System (INIS)

    Thang Manh Hoang

    2009-01-01

    We present the transition among possible synchronous schemes in coupled nonidentical multiple time delay systems, i.e., lag, projective-lag, complete, anticipating and projective-anticipating synchronization. The number of nonlinear transforms in the master's equation can be different from that in slave's, and nonlinear transforms can be in various forms. The driving signal is the sum of nonlinearly transformed components of delayed state variable. Moreover, the equation representing for driving signal is constructed exactly so that the difference between the master's and slave's structures is complemented. The sufficient condition for synchronization is considered by the Krasovskii-Lyapunov theory. The specific examples will demonstrate and verify the effectiveness of the proposed models.

  19. A low-order coupled chemistry meteorology model for testing online and offline data assimilation schemes

    Science.gov (United States)

    Haussaire, J.-M.; Bocquet, M.

    2015-08-01

    Bocquet and Sakov (2013) have introduced a low-order model based on the coupling of the chaotic Lorenz-95 model which simulates winds along a mid-latitude circle, with the transport of a tracer species advected by this zonal wind field. This model, named L95-T, can serve as a playground for testing data assimilation schemes with an online model. Here, the tracer part of the model is extended to a reduced photochemistry module. This coupled chemistry meteorology model (CCMM), the L95-GRS model, mimics continental and transcontinental transport and the photochemistry of ozone, volatile organic compounds and nitrogen oxides. Its numerical implementation is described. The model is shown to reproduce the major physical and chemical processes being considered. L95-T and L95-GRS are specifically designed and useful for testing advanced data assimilation schemes, such as the iterative ensemble Kalman smoother (IEnKS) which combines the best of ensemble and variational methods. These models provide useful insights prior to the implementation of data assimilation methods on larger models. We illustrate their use with data assimilation schemes on preliminary, yet instructive numerical experiments. In particular, online and offline data assimilation strategies can be conveniently tested and discussed with this low-order CCMM. The impact of observed chemical species concentrations on the wind field can be quantitatively estimated. The impacts of the wind chaotic dynamics and of the chemical species non-chaotic but highly nonlinear dynamics on the data assimilation strategies are illustrated.

  20. DYNSUB: A high fidelity coupled code system for the evaluation of local safety parameters – Part II: Comparison of different temporal schemes

    International Nuclear Information System (INIS)

    Gomez-Torres, Armando Miguel; Sanchez-Espinoza, Victor Hugo; Ivanov, Kostadin; Macian-Juan, Rafael

    2012-01-01

    Highlights: ► A fixed point iteration (FPI) is implemented in DYNSUB. ► Comparisons between the explicit scheme and the FPI are done. ► The FPI scheme allows moving from one time step to the other with converged solution. ► FPI allows the use of larger time steps without compromising the accuracy of results. ► FPI results are promising and represent an option in order to optimize calculations. -- Abstract: DYNSUB is a novel two-way pin-based coupling of the simplified transport (SP 3 ) version of DYN3D with the subchannel code SUBCHANFLOW. The new coupled code system allows for a more realistic description of the core behaviour under steady state and transients conditions, and has been widely described in Part I of this paper. Additionally to the explicit coupling developed and described in Part I, a nested loop iteration or fixed point iteration (FPI) is implemented in DYNSUB. A FPI is not an implicit scheme but approximates it by adding an iteration loop to the current explicit scheme. The advantage of the method is that it allows the use of larger time steps; however the nested loop iteration could take much more time in getting a converged solution that could be less efficient than the explicit scheme with small time steps. A comparison of the two temporal schemes is performed. The results using FPI are very promising and represent a very good option in order to optimize computational times without losing accuracy. However it is also shown that a FPI scheme can produce inaccurate results if the time step is not chosen in agreement with the analyzed transient.

  1. A study on different thermodynamic cycle schemes coupled with a high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Qu, Xinhe; Yang, Xiaoyong; Wang, Jie

    2017-01-01

    Highlights: • The features of three different power generation schemes, including closed Brayton cycle, non-reheating combined cycle and reheating combined cycle, coupled with high temperature gas-cooled reactor (HTGR) were investigated and compared. • The effects and mechanism of reactor core outlet temperature, compression ratio and other key parameters over cycle characteristics were analyzed by the thermodynamic models.. • It is found that reheated combined cycle has the highest efficiency. Reactor outlet temperature and main steam parameters are key factors to improve the cycle’s performance. - Abstract: With gradual increase in reactor outlet temperature, the efficient power conversion technology has become one of developing trends of (very) high temperature gas-cooled reactors (HTGRs). In this paper, different cycle power generation schemes for HTGRs were systematically studied. Physical and mathematical models were established for these three cycle schemes: closed Brayton cycle, simple combined cycle, and reheated combined cycle. The effects and mechanism of key parameters such as reactor core outlet temperature, reactor core inlet temperature and compression ratio on the features of these cycles were analyzed. Then, optimization results were given with engineering restrictive conditions, including pinch point temperature differences. Results revealed that within the temperature range of HTGRs (700–900 °C), the reheated combined cycle had the highest efficiency, while the simple combined cycle had the lowest efficiency (900 °C). The efficiencies of the closed Brayton cycle, simple combined cycle and reheated combined cycle are 49.5%, 46.6% and 50.1%, respectively. These results provide insights on the different schemes of these cycles, and reveal the effects of key parameters on performance of these cycles. It could be helpful to understand and develop a combined cycle coupled with a high temperature reactor in the future.

  2. Axisymmetric alternating direction explicit scheme for efficient coupled simulation of hydro-mechanical interaction in geotechnical engineering—Application to circular footing and deep tunnel in saturated ground

    Directory of Open Access Journals (Sweden)

    Simon Heru Prassetyo

    2018-04-01

    Full Text Available Explicit solution techniques have been widely used in geotechnical engineering for simulating the coupled hydro-mechanical (H-M interaction of fluid flow and deformation induced by structures built above and under saturated ground, i.e. circular footing and deep tunnel. However, the technique is only conditionally stable and requires small time steps, portending its inefficiency for simulating large-scale H-M problems. To improve its efficiency, the unconditionally stable alternating direction explicit (ADE scheme could be used to solve the flow problem. The standard ADE scheme, however, is only moderately accurate and is restricted to uniform grids and plane strain flow conditions. This paper aims to remove these drawbacks by developing a novel high-order ADE scheme capable of solving flow problems in non-uniform grids and under axisymmetric conditions. The new scheme is derived by performing a fourth-order finite difference (FD approximation to the spatial derivatives of the axisymmetric fluid–diffusion equation in a non-uniform grid configuration. The implicit Crank-Nicolson technique is then applied to the resulting approximation, and the subsequent equation is split into two alternating direction sweeps, giving rise to a new axisymmetric ADE scheme. The pore pressure solutions from the new scheme are then sequentially coupled with an existing geomechanical simulator in the computer code fast Lagrangian analysis of continua (FLAC. This coupling procedure is called the sequentially-explicit coupling technique based on the fourth-order axisymmetric ADE scheme or SEA-4-AXI. Application of SEA-4-AXI for solving axisymmetric consolidation of a circular footing and of advancing tunnel in deep saturated ground shows that SEA-4-AXI reduces computer runtime up to 42%–50% that of FLAC's basic scheme without numerical instability. In addition, it produces high numerical accuracy of the H-M solutions with average percentage difference of only 0.5%

  3. Standard LS-TTL IC data book

    International Nuclear Information System (INIS)

    1997-05-01

    This book is one of semiconductor device data manual series. It introduces standard logic 74LS fast series. It has general information, circuit characteristic, note of design and test and FAST Data Sheets, which includes gates, Flip-Flop, Decoder and Encoder, Counter, Master reset, Counter, Shift register, octal Buffer/Line Driver/3-state, generator/Checker, Full adder, Error Detection and correction circuit controller and synchronous address Multiplexer. It also lists LS Data Sheets including NAND gate, NOR gate, Hex Inverter, Delay Element, Frequency Divider, Decode Counter, Function generator, Dual Decode Counter, Memory cycle controller and voltage controlled Oscillator.

  4. Safety, Quality, Schedule: the motto of LS1

    CERN Multimedia

    2013-01-01

    The LHC’s first long shutdown, LS1, is a marathon that began on 16 February and will take us through to the beginning of 2015. Just as Olympic marathon runners have a motto, Citius, Altius, Fortius, so the athletes of LS1 work to the mantra of Safety, Quality, Schedule. Four months into LS1, they have settled into their rhythm, and things are going to plan.   The first task of LS1 was to bring the LHC up to room temperature - this was achieved in just 10 weeks. In parallel, preliminary tests for electrical quality assurance and leaks revealed essentially the level of wear and tear we’d expect after three years of running. One slightly anxious moment came when we looked at the RF fingers – the devices that ensure electrical contact in the beam pipes as they pass from one magnet to the next. Those of you with long memories will recall that before start-up, some of these got damaged at warm-up. The good news today is that with all eight sectors test...

  5. Quenches after LS1

    International Nuclear Information System (INIS)

    Verweij, A.P.

    2012-01-01

    In this paper I will give an overview of the different types of quenches that occur in the LHC, followed by an estimate of the number of quenches that we can expect after LS1. Beam-induced quenches and false triggering of the QPS will be the main cause of those quenches that cause a beam dump. Possibly in total up to 10-20 per year. After consolidation of the 13 kA joints, the approach for the BLM settings can be less conservative than in 2010-2012 in order to maximize beam time. This will cause some quenches but, anyhow, a beam.induced quench is not more risky than a quench provoked by false triggering. It is not easy to predict the number of BLM triggered beam dumps, needed to avoid magnet quenches, because it is not sure how to scale beam losses and UFO's from 3.5 TeV to 6.5 TeV, and it is not sure if the thresholds at 3.5 TeV are correct. Quench events will be much more massive (ex: RB quench at 6 kA → 2 MJ, RB quench at 11 kA → 6-20 MJ), and as a result cryo recuperation much longer. There will also be more ramp induced quenches after a FPA in other circuits due to higher ramp rates and smaller temperature margins (mutual coupling)

  6. Decon2LS: An open-source software package for automated processing and visualization of high resolution mass spectrometry data.

    Science.gov (United States)

    Jaitly, Navdeep; Mayampurath, Anoop; Littlefield, Kyle; Adkins, Joshua N; Anderson, Gordon A; Smith, Richard D

    2009-03-17

    Data generated from liquid chromatography coupled to high-resolution mass spectrometry (LC-MS)-based studies of a biological sample can contain large amounts of biologically significant information in the form of proteins, peptides, and metabolites. Interpreting this data involves inferring the masses and abundances of biomolecules injected into the instrument. Because of the inherent complexity of mass spectral patterns produced by these biomolecules, the analysis is significantly enhanced by using visualization capabilities to inspect and confirm results. In this paper we describe Decon2LS, an open-source software package for automated processing and visualization of high-resolution MS data. Drawing extensively on algorithms developed over the last ten years for ICR2LS, Decon2LS packages the algorithms as a rich set of modular, reusable processing classes for performing diverse functions such as reading raw data, routine peak finding, theoretical isotope distribution modelling, and deisotoping. Because the source code is openly available, these functionalities can now be used to build derivative applications in relatively fast manner. In addition, Decon2LS provides an extensive set of visualization tools, such as high performance chart controls. With a variety of options that include peak processing, deisotoping, isotope composition, etc, Decon2LS supports processing of multiple raw data formats. Deisotoping can be performed on an individual scan, an individual dataset, or on multiple datasets using batch processing. Other processing options include creating a two dimensional view of mass and liquid chromatography (LC) elution time features, generating spectrum files for tandem MS data, creating total intensity chromatograms, and visualizing theoretical peptide profiles. Application of Decon2LS to deisotope different datasets obtained across different instruments yielded a high number of features that can be used to identify and quantify peptides in the

  7. LS1: electrical engineering upgrades and consolidation

    International Nuclear Information System (INIS)

    Duval, F.

    2012-01-01

    3 different types of activities are planned by the Engineering Department Electrical Engineering (EN-EL) Group for the first long shut down (LS1). First, the consolidation of EN-EL's ageing infrastructure elements. It is part of a 15- year programme aiming at increasing the reliability and availability of the power distribution network. Secondly, the maintenance of the accelerators infrastructure. In addition to the usual periodic operations and those delayed until LS1, the group will address more demanding activities like the replacement campaigns for irradiated cables and non-radiation resistant fibres as well as the removal of unused cables in particularly overcrowded areas. Thirdly, a vast amount of user copper and optical fibre cabling requests: EN-EL estimates that only 50% of LS1 requests are currently known. The main activities will be EN-EL's contributions to the R2E project, BE-BI upgrade projects, and the RF upgrade project in SPS BA3

  8. LS1 general planning and strategy for the LHC, LHC injectors

    International Nuclear Information System (INIS)

    Foraz, K.

    2012-01-01

    The goal of Long Shutdown 1 (LS1) is to perform the full maintenance of equipment and the necessary consolidation and upgrade activities in order to ensure reliable LHC operation at nominal performance from mid-2014. LS1 is scheduled to last 20 months. LS1 not only concerns the LHC but also its injectors. To ensure resources will be available an analysis is in progress to detect conflict/overload and decide what is compulsory, what we can afford, and what can be postponed until LS2. The strategy, time key drivers, constraints, and draft schedule are presented here. (author)

  9. Extending JPEG-LS for low-complexity scalable video coding

    DEFF Research Database (Denmark)

    Ukhanova, Anna; Sergeev, Anton; Forchhammer, Søren

    2011-01-01

    JPEG-LS, the well-known international standard for lossless and near-lossless image compression, was originally designed for non-scalable applications. In this paper we propose a scalable modification of JPEG-LS and compare it with the leading image and video coding standards JPEG2000 and H.264/SVC...

  10. Coupled assimilation for an intermediated coupled ENSO prediction model

    Science.gov (United States)

    Zheng, Fei; Zhu, Jiang

    2010-10-01

    The value of coupled assimilation is discussed using an intermediate coupled model in which the wind stress is the only atmospheric state which is slavery to model sea surface temperature (SST). In the coupled assimilation analysis, based on the coupled wind-ocean state covariance calculated from the coupled state ensemble, the ocean state is adjusted by assimilating wind data using the ensemble Kalman filter. As revealed by a series of assimilation experiments using simulated observations, the coupled assimilation of wind observations yields better results than the assimilation of SST observations. Specifically, the coupled assimilation of wind observations can help to improve the accuracy of the surface and subsurface currents because the correlation between the wind and ocean currents is stronger than that between SST and ocean currents in the equatorial Pacific. Thus, the coupled assimilation of wind data can decrease the initial condition errors in the surface/subsurface currents that can significantly contribute to SST forecast errors. The value of the coupled assimilation of wind observations is further demonstrated by comparing the prediction skills of three 12-year (1997-2008) hindcast experiments initialized by the ocean-only assimilation scheme that assimilates SST observations, the coupled assimilation scheme that assimilates wind observations, and a nudging scheme that nudges the observed wind stress data, respectively. The prediction skills of two assimilation schemes are significantly better than those of the nudging scheme. The prediction skills of assimilating wind observations are better than assimilating SST observations. Assimilating wind observations for the 2007/2008 La Niña event triggers better predictions, while assimilating SST observations fails to provide an early warning for that event.

  11. Ultrafast demagnetization in rare-earth alloys: the role of spin-orbit coupling

    Energy Technology Data Exchange (ETDEWEB)

    Le Guyader, Loic; Solopow, Sergej; Radu, Florin; Holldack, Karsten; Mitzner, Rolf; Kachel, Torsten; Pontius, Niko; Foehlisch, Alexander; Radu, Ilie [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Abrudan, Radu [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Institut fuer Experimentalphysik/Festkoerperphysik, Ruhr-Universitaet Bochum (Germany)

    2015-07-01

    Understanding the ultrafast demagnetization occurring upon femtosecond laser excitation of a magnetic material is a fundamental problem of modern magnetism and its microscopic origin remains highly elusive and intensely debated. Particularly, the spin-orbit coupling mediating the spin-lattice interaction is one of the key ingredients. An intriguing case of tunable parallel to anti-parallel LS coupling can be realized in rare-earth (RE) alloys. For instance, Gd60Sm40 and Gd60Dy40 alloys have similar absolute S and L, but exhibit opposite LS coupling while displaying the same ferromagnetic ordering temperature of 250 K. They constitute thus an ideal case to investigate the particular role of the LS coupling on the ultrafast demagnetization. Here we report on the properties of such RE thin film alloys using X-ray Magnetic Circular Dichroism (XMCD) with the spin and orbit sum rules at M5,4 edges. Femtosecond time-resolved transmission XMCD measurements performed at the slicing beamline reveal the element-specific demagnetization time constant in these alloys. Funding from European Union through FEMTOSPIN is gratefully acknowledged.

  12. Decon2LS: An open-source software package for automated processing and visualization of high resolution mass spectrometry data

    Directory of Open Access Journals (Sweden)

    Anderson Gordon A

    2009-03-01

    Full Text Available Abstract Background Data generated from liquid chromatography coupled to high-resolution mass spectrometry (LC-MS-based studies of a biological sample can contain large amounts of biologically significant information in the form of proteins, peptides, and metabolites. Interpreting this data involves inferring the masses and abundances of biomolecules injected into the instrument. Because of the inherent complexity of mass spectral patterns produced by these biomolecules, the analysis is significantly enhanced by using visualization capabilities to inspect and confirm results. In this paper we describe Decon2LS, an open-source software package for automated processing and visualization of high-resolution MS data. Drawing extensively on algorithms developed over the last ten years for ICR2LS, Decon2LS packages the algorithms as a rich set of modular, reusable processing classes for performing diverse functions such as reading raw data, routine peak finding, theoretical isotope distribution modelling, and deisotoping. Because the source code is openly available, these functionalities can now be used to build derivative applications in relatively fast manner. In addition, Decon2LS provides an extensive set of visualization tools, such as high performance chart controls. Results With a variety of options that include peak processing, deisotoping, isotope composition, etc, Decon2LS supports processing of multiple raw data formats. Deisotoping can be performed on an individual scan, an individual dataset, or on multiple datasets using batch processing. Other processing options include creating a two dimensional view of mass and liquid chromatography (LC elution time features, generating spectrum files for tandem MS data, creating total intensity chromatograms, and visualizing theoretical peptide profiles. Application of Decon2LS to deisotope different datasets obtained across different instruments yielded a high number of features that can be used to

  13. Scheme for implementing N-qubit controlled phase gate of photons assisted by quantum-dot-microcavity coupled system: optimal probability of success

    International Nuclear Information System (INIS)

    Cui, Wen-Xue; Hu, Shi; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

    2015-01-01

    The direct implementation of multiqubit controlled phase gate of photons is appealing and important for reducing the complexity of the physical realization of linear-optics-based practical quantum computer and quantum algorithms. In this letter we propose a nondestructive scheme for implementing an N-qubit controlled phase gate of photons with a high success probability. The gate can be directly implemented with the self-designed quantum encoder circuits, which are probabilistic optical quantum entangler devices and can be achieved using linear optical elements, single-photon superposition state, and quantum dot coupled to optical microcavity. The calculated results indicate that both the success probabilities of the quantum encoder circuit and the N-qubit controlled phase gate in our scheme are higher than those in the previous schemes. We also consider the effects of the side leakage and cavity loss on the success probability and the fidelity of the quantum encoder circuit for a realistic quantum-dot-microcavity coupled system. (letter)

  14. Revitalising Mathematics Classroom Teaching through Lesson Study (LS): A Malaysian Case Study

    Science.gov (United States)

    Lim, Chap Sam; Kor, Liew Kee; Chia, Hui Min

    2016-01-01

    This paper discusses how implementation of Lesson Study (LS) has brought about evolving changes in the quality of mathematics classroom teaching in one Chinese primary school. The Japanese model of LS was adapted as a teacher professional development to improve mathematics teachers' teaching practices. The LS group consisted of five mathematics…

  15. PSO-tuned PID controller for coupled tank system via priority-based fitness scheme

    Science.gov (United States)

    Jaafar, Hazriq Izzuan; Hussien, Sharifah Yuslinda Syed; Selamat, Nur Asmiza; Abidin, Amar Faiz Zainal; Aras, Mohd Shahrieel Mohd; Nasir, Mohamad Na'im Mohd; Bohari, Zul Hasrizal

    2015-05-01

    The industrial applications of Coupled Tank System (CTS) are widely used especially in chemical process industries. The overall process is require liquids to be pumped, stored in the tank and pumped again to another tank. Nevertheless, the level of liquid in tank need to be controlled and flow between two tanks must be regulated. This paper presents development of an optimal PID controller for controlling the desired liquid level of the CTS. Two method of Particle Swarm Optimization (PSO) algorithm will be tested in optimizing the PID controller parameters. These two methods of PSO are standard Particle Swarm Optimization (PSO) and Priority-based Fitness Scheme in Particle Swarm Optimization (PFPSO). Simulation is conducted within Matlab environment to verify the performance of the system in terms of settling time (Ts), steady state error (SSE) and overshoot (OS). It has been demonstrated that implementation of PSO via Priority-based Fitness Scheme (PFPSO) for this system is potential technique to control the desired liquid level and improve the system performances compared with standard PSO.

  16. Biodegradation test of SPS-LS blends as polymer electrolyte membrane fuel cells

    International Nuclear Information System (INIS)

    Putri, Zufira; Arcana, I Made

    2014-01-01

    Sulfonated polystyrene (SPS) can be applied as a proton exchange membrane fuel cell due to its fairly good chemical stability. In order to be applied as polymer electrolyte membrane fuel cells (PEMFCs), membrane polymer should have a good ionic conductivity, high proton conductivity, and high mechanical strength. Lignosulfonate (LS) is a complex biopolymer which has crosslinks and sulfonate groups. SPS-LS blends with addition of SiO 2 are used to increase the proton conductivity and to improve the mechanical properties and thermal stability. However, the biodegradation test of SPS-LS blends is required to determine whether the application of these membranes to be applied as an environmentally friendly membrane. In this study, had been done the synthesis of SPS, biodegradability test of SPS-LS blends with variations of LS and SiO 2 compositions. The biodegradation test was carried out in solid medium of Luria Bertani (LB) with an activated sludge used as a source of microorganism at incubation temperature of 37°C. Based on the results obtained indicated that SPS-LS-SiO 2 blends are more decomposed by microorganism than SPS-LS blends. This result is supported by analysis of weight reduction percentage, functional groups with Fourier Transform Infrared (FTIR) Spectroscopy, and morphological surface with Scanning Electron Microscopy (SEM)

  17. SPS completes LS1 activities

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    On 27 June, the SPS closed its doors to the LS1 engineers, bringing to an end almost 17 months of activities. The machine now enters the hardware-testing phase in preparation for an October restart.   Photo 1: The SPS transfer tunnel, TT10, reinforced with steal beams. Having completed their LS1 activities right on schedule (to the day!), the SPS team is now preparing the machine for its restart. Over the next eight weeks, hardware tests of the SPS dipole and quadrupole power converters will be underway, led by the TE-EPC (Electrical Power Converters) team. "OP start-up test activities will also be running in parallel, utilising the off hours when EPC is not using the machine," says David McFarlane, the SPS technical coordinator from the Engineering Department. "The primary beam testing phase will start at the beginning of September, once hardware tests and DSO safety tests have been completed." It has been a long journey to this point, with several major...

  18. Convergence of numerical schemes suitable for two dimensional nonlinear convection: application to the coupling of modes in a plasma

    International Nuclear Information System (INIS)

    Boukadida, T.

    1988-01-01

    The compatibility between accuracy and stability of the quasilinear equations is studied. Three stuations are analyzed: the discontinuous P-1 approximation of the first order quasilinear equation, the two dimensional version of the Lax-Friedrichs scheme and the coupling of modes in a plasma. For the one dimensional case, the proposed scheme matches the available data. In the two dimensional case, tests to show the explosion condition are performed. This investigation can be applied in laser-matter interactions, nonlinear optics and in many fields of physics [fr

  19. Salt Selection for the LS-VHTR

    International Nuclear Information System (INIS)

    Williams, D.F.; Clarno, K.T.

    2006-01-01

    Molten fluorides were initially developed for use in the nuclear industry as the high temperature fluid-fuel for a Molten Salt Reactor (MSR). The Office of Nuclear Energy is exploring the use of molten fluorides as a primary coolant (rather than helium) in an Advanced High Temperature Reactor (AHTR) design, also know as the Liquid-Salt cooled Very High Temperature Reactor (LS-VHTR). This paper provides a review of relevant properties for use in evaluation and ranking of candidate coolants for the LS-VHTR. Nuclear, physical, and chemical properties were reviewed and metrics for evaluation are recommended. Chemical properties of the salt were examined for the purpose of identifying factors that effect materials compatibility (i.e., corrosion). Some preliminary consideration of economic factors for the candidate salts is also presented. (authors)

  20. Biodegradation test of SPS-LS blends as polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Putri, Zufira, E-mail: zufira.putri@gmail.com, E-mail: arcana@chem.itb.ac.id; Arcana, I Made, E-mail: zufira.putri@gmail.com, E-mail: arcana@chem.itb.ac.id [Inorganic and Physical Chemistry Research Groups, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung (Indonesia)

    2014-03-24

    Sulfonated polystyrene (SPS) can be applied as a proton exchange membrane fuel cell due to its fairly good chemical stability. In order to be applied as polymer electrolyte membrane fuel cells (PEMFCs), membrane polymer should have a good ionic conductivity, high proton conductivity, and high mechanical strength. Lignosulfonate (LS) is a complex biopolymer which has crosslinks and sulfonate groups. SPS-LS blends with addition of SiO{sub 2} are used to increase the proton conductivity and to improve the mechanical properties and thermal stability. However, the biodegradation test of SPS-LS blends is required to determine whether the application of these membranes to be applied as an environmentally friendly membrane. In this study, had been done the synthesis of SPS, biodegradability test of SPS-LS blends with variations of LS and SiO{sub 2} compositions. The biodegradation test was carried out in solid medium of Luria Bertani (LB) with an activated sludge used as a source of microorganism at incubation temperature of 37°C. Based on the results obtained indicated that SPS-LS-SiO{sub 2} blends are more decomposed by microorganism than SPS-LS blends. This result is supported by analysis of weight reduction percentage, functional groups with Fourier Transform Infrared (FTIR) Spectroscopy, and morphological surface with Scanning Electron Microscopy (SEM)

  1. Coherence features of the spin-aligned neutron-proton pair coupling scheme

    International Nuclear Information System (INIS)

    Qi, C; Blomqvist, J; Bäck, T; Cederwall, B; Johnson, A; Liotta, R J; Wyss, R

    2012-01-01

    The seniority scheme has been shown to be extremely useful for the classification of nuclear states in semi-magic nuclei. The neutron-proton (np) correlation breaks the seniority symmetry in a major way. As a result, the corresponding wave function is a mixture of many components with different seniority quantum numbers. In this paper, we show that the np interaction may favor a new kind of coupling in N=Z nuclei, i.e. the so-called isoscalar spin-aligned np pair mode. Shell model calculations reveal that the ground and low-lying yrast states of the N=Z nuclei 92 Pd and 96 Cd may be mainly built upon such spin-aligned np pairs, each carrying the maximum angular momentum J=9 allowed by the shell 0 g 9/2 which is dominant in this nuclear region.

  2. LS1 general planning and strategy for the LHC, LHC injectors

    CERN Document Server

    Foraz, K

    2012-01-01

    The goal of Long Shutdown 1 (LS1) is to perform the full maintenance of equipment, and the necessary consolidation and upgrade activities in order to ensure reliable LHC operation at nominal performance from mid 2014. LS1 not only concerns LHC but also its injectors. To ensure resources will be available an analysis is in progress to detect conflict/overload and decide what is compulsary, what we can afford, and what can be postponed to LS2. The strategy, time key drivers, constraints, and draft schedule will be presented here.

  3. Regional-scale calculation of the LS factor using parallel processing

    Science.gov (United States)

    Liu, Kai; Tang, Guoan; Jiang, Ling; Zhu, A.-Xing; Yang, Jianyi; Song, Xiaodong

    2015-05-01

    With the increase of data resolution and the increasing application of USLE over large areas, the existing serial implementation of algorithms for computing the LS factor is becoming a bottleneck. In this paper, a parallel processing model based on message passing interface (MPI) is presented for the calculation of the LS factor, so that massive datasets at a regional scale can be processed efficiently. The parallel model contains algorithms for calculating flow direction, flow accumulation, drainage network, slope, slope length and the LS factor. According to the existence of data dependence, the algorithms are divided into local algorithms and global algorithms. Parallel strategy are designed according to the algorithm characters including the decomposition method for maintaining the integrity of the results, optimized workflow for reducing the time taken for exporting the unnecessary intermediate data and a buffer-communication-computation strategy for improving the communication efficiency. Experiments on a multi-node system show that the proposed parallel model allows efficient calculation of the LS factor at a regional scale with a massive dataset.

  4. Prediction of the strength of concrete radiation shielding based on LS-SVM

    International Nuclear Information System (INIS)

    Juncai, Xu; Qingwen, Ren; Zhenzhong, Shen

    2015-01-01

    Highlights: • LS-SVM was introduced for prediction of the strength of RSC. • A model for prediction of the strength of RSC was implemented. • The grid search algorithm was used to optimize the parameters of the LS-SVM. • The performance of LS-SVM in predicting the strength of RSC was evaluated. - Abstract: Radiation-shielding concrete (RSC) and conventional concrete differ in strength because of their distinct constituents. Predicting the strength of RSC with different constituents plays a vital role in radiation shielding (RS) engineering design. In this study, a model to predict the strength of RSC is established using a least squares-support vector machine (LS-SVM) through grid search algorithm. The algorithm is used to optimize the parameters of the LS-SVM on the basis of traditional prediction methods for conventional concrete. The predicted results of the LS-SVM model are compared with the experimental data. The results of the prediction are stable and consistent with the experimental results. In addition, the studied parameters exhibit significant effects on the simulation results. Therefore, the proposed method can be applied in predicting the strength of RSC, and the predicted results can be adopted as an important reference for RS engineering design

  5. A scheme for the hadron spectrum

    International Nuclear Information System (INIS)

    Hoyer, P.

    1978-03-01

    A theoretically self-consistent dual scheme is proposed for the hadron spectrum, which follows naturally from basic requirements and phenomenology. All resonance properties and couplings are calculable in terms of a limited number of input parameters. A first application to ππ→ππ explains the linear trajectory and small daughter couplings. The Zweig rule and the decoupling of baryonium from mesons are expected to be consequences of the scheme. (Auth.)

  6. People typically experience extended periods of relative happiness or unhappiness due to positive feedback loops between LS and variables which are both causes and consequences of LS

    NARCIS (Netherlands)

    Headey, Bruce; Muffels, R.J.A.

    2015-01-01

    Long term panel data enable researchers to construct trajectories of LS for individuals over time. Bar charts of trajectories, and subsequent statistical analysis, show that respondents typically spend multiple consecutive years above and below their own long-term mean level of LS. We attempt to

  7. Effect of Lactobacillus salivarius Ls-33 on fecal microbiota in obese adolescents.

    Science.gov (United States)

    Larsen, Nadja; Vogensen, Finn K; Gøbel, Rikke Juul; Michaelsen, Kim F; Forssten, Sofia D; Lahtinen, Sampo J; Jakobsen, Mogens

    2013-12-01

    This study is a part of the clinical trials with probiotic bacterium Lactobacillus salivarius Ls-33 conducted in obese adolescents. Previously reported clinical studies showed no effect of Ls-33 consumption on the metabolic syndrome in the subject group. The aim of the study was to investigate the impact of L. salivarius Ls-33 on fecal microbiota in obese adolescents. The study was a double-blinded intervention with 50 subjects randomized to intake of L. salivarius Ls-33 or placebo for 12 weeks. The fecal microbiota was assessed by real-time quantitative PCR before and after intervention. Concentrations of fecal short chain fatty acids were determined using gas chromatography. Ratios of Bacteroides-Prevotella-Porphyromonas group to Firmicutes belonging bacteria, including Clostridium cluster XIV, Blautia coccoides_Eubacteria rectale group and Roseburia intestinalis, were significantly increased (p ≤ 0.05) after administration of Ls-33. The cell numbers of fecal bacteria, including the groups above as well as Clostridium cluster I, Clostridium cluster IV, Faecalibacterium prausnitzii, Enterobacteriaceae, Enterococcus, the Lactobacillus group and Bifidobacterium were not significantly altered by intervention. Similarly, short chain fatty acids remained unaffected. L. salivarius Ls-33 might modify the fecal microbiota in obese adolescents in a way not related to metabolic syndrome. NCT 01020617. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  8. A cavity-Cooper pair transistor scheme for investigating quantum optomechanics in the ultra-strong coupling regime

    International Nuclear Information System (INIS)

    Rimberg, A J; Blencowe, M P; Armour, A D; Nation, P D

    2014-01-01

    We propose a scheme involving a Cooper pair transistor (CPT) embedded in a superconducting microwave cavity, where the CPT serves as a charge tunable quantum inductor to facilitate ultra-strong coupling between photons in the cavity and a nano- to meso-scale mechanical resonator. The mechanical resonator is capacitively coupled to the CPT, such that mechanical displacements of the resonator cause a shift in the CPT inductance and hence the cavity's resonant frequency. The amplification provided by the CPT is sufficient for the zero point motion of the mechanical resonator alone to cause a significant change in the cavity resonance. Conversely, a single photon in the cavity causes a shift in the mechanical resonator position on the order of its zero point motion. As a result, the cavity-Cooper pair transistor coupled to a mechanical resonator will be able to access a regime in which single photons can affect single phonons and vice versa. Realizing this ultra-strong coupling regime will facilitate the creation of non-classical states of the mechanical resonator, as well as the means to accurately characterize such states by measuring the cavity photon field. (paper)

  9. A novel efficient coupled polynomial field interpolation scheme for higher order piezoelectric extension mode beam finite elements

    International Nuclear Information System (INIS)

    Sulbhewar, Litesh N; Raveendranath, P

    2014-01-01

    An efficient piezoelectric smart beam finite element based on Reddy’s third-order displacement field and layerwise linear potential is presented here. The present formulation is based on the coupled polynomial field interpolation of variables, unlike conventional piezoelectric beam formulations that use independent polynomials. Governing equations derived using a variational formulation are used to establish the relationship between field variables. The resulting expressions are used to formulate coupled shape functions. Starting with an assumed cubic polynomial for transverse displacement (w) and a linear polynomial for electric potential (φ), coupled polynomials for axial displacement (u) and section rotation (θ) are found. This leads to a coupled quadratic polynomial representation for axial displacement (u) and section rotation (θ). The formulation allows accommodation of extension–bending, shear–bending and electromechanical couplings at the interpolation level itself, in a variationally consistent manner. The proposed interpolation scheme is shown to eliminate the locking effects exhibited by conventional independent polynomial field interpolations and improve the convergence characteristics of HSDT based piezoelectric beam elements. Also, the present coupled formulation uses only three mechanical degrees of freedom per node, one less than the conventional formulations. Results from numerical test problems prove the accuracy and efficiency of the present formulation. (paper)

  10. A multiscale fixed stress split iterative scheme for coupled flow and poromechanics in deep subsurface reservoirs

    Science.gov (United States)

    Dana, Saumik; Ganis, Benjamin; Wheeler, Mary F.

    2018-01-01

    In coupled flow and poromechanics phenomena representing hydrocarbon production or CO2 sequestration in deep subsurface reservoirs, the spatial domain in which fluid flow occurs is usually much smaller than the spatial domain over which significant deformation occurs. The typical approach is to either impose an overburden pressure directly on the reservoir thus treating it as a coupled problem domain or to model flow on a huge domain with zero permeability cells to mimic the no flow boundary condition on the interface of the reservoir and the surrounding rock. The former approach precludes a study of land subsidence or uplift and further does not mimic the true effect of the overburden on stress sensitive reservoirs whereas the latter approach has huge computational costs. In order to address these challenges, we augment the fixed-stress split iterative scheme with upscaling and downscaling operators to enable modeling flow and mechanics on overlapping nonmatching hexahedral grids. Flow is solved on a finer mesh using a multipoint flux mixed finite element method and mechanics is solved on a coarse mesh using a conforming Galerkin method. The multiscale operators are constructed using a procedure that involves singular value decompositions, a surface intersections algorithm and Delaunay triangulations. We numerically demonstrate the convergence of the augmented scheme using the classical Mandel's problem solution.

  11. Performance of extended Lagrangian schemes for molecular dynamics simulations with classical polarizable force fields and density functional theory.

    Science.gov (United States)

    Vitale, Valerio; Dziedzic, Jacek; Albaugh, Alex; Niklasson, Anders M N; Head-Gordon, Teresa; Skylaris, Chris-Kriton

    2017-03-28

    Iterative energy minimization with the aim of achieving self-consistency is a common feature of Born-Oppenheimer molecular dynamics (BOMD) and classical molecular dynamics with polarizable force fields. In the former, the electronic degrees of freedom are optimized, while the latter often involves an iterative determination of induced point dipoles. The computational effort of the self-consistency procedure can be reduced by re-using converged solutions from previous time steps. However, this must be done carefully, as not to break time-reversal symmetry, which negatively impacts energy conservation. Self-consistent schemes based on the extended Lagrangian formalism, where the initial guesses for the optimized quantities are treated as auxiliary degrees of freedom, constitute one elegant solution. We report on the performance of two integration schemes with the same underlying extended Lagrangian structure, which we both employ in two radically distinct regimes-in classical molecular dynamics simulations with the AMOEBA polarizable force field and in BOMD simulations with the Onetep linear-scaling density functional theory (LS-DFT) approach. Both integration schemes are found to offer significant improvements over the standard (unpropagated) molecular dynamics formulation in both the classical and LS-DFT regimes.

  12. LS-SNP/PDB: annotated non-synonymous SNPs mapped to Protein Data Bank structures.

    Science.gov (United States)

    Ryan, Michael; Diekhans, Mark; Lien, Stephanie; Liu, Yun; Karchin, Rachel

    2009-06-01

    LS-SNP/PDB is a new WWW resource for genome-wide annotation of human non-synonymous (amino acid changing) SNPs. It serves high-quality protein graphics rendered with UCSF Chimera molecular visualization software. The system is kept up-to-date by an automated, high-throughput build pipeline that systematically maps human nsSNPs onto Protein Data Bank structures and annotates several biologically relevant features. LS-SNP/PDB is available at (http://ls-snp.icm.jhu.edu/ls-snp-pdb) and via links from protein data bank (PDB) biology and chemistry tabs, UCSC Genome Browser Gene Details and SNP Details pages and PharmGKB Gene Variants Downloads/Cross-References pages.

  13. LS-SVM: uma nova ferramenta quimiométrica para regressão multivariada. Comparação de modelos de regressão LS-SVM e PLS na quantificação de adulterantes em leite em pó empregando NIR LS-SVM: a new chemometric tool for multivariate regression. Comparison of LS-SVM and pls regression for determination of common adulterants in powdered milk by nir spectroscopy

    Directory of Open Access Journals (Sweden)

    Marco F. Ferrão

    2007-08-01

    Full Text Available Least-squares support vector machines (LS-SVM were used as an alternative multivariate calibration method for the simultaneous quantification of some common adulterants found in powdered milk samples, using near-infrared spectroscopy. Excellent models were built using LS-SVM for determining R², RMSECV and RMSEP values. LS-SVMs show superior performance for quantifying starch, whey and sucrose in powdered milk samples in relation to PLSR. This study shows that it is possible to determine precisely the amount of one and two common adulterants simultaneously in powdered milk samples using LS-SVM and NIR spectra.

  14. Performance potential of the injectors after LS1

    International Nuclear Information System (INIS)

    Bartosik, H.; Carli, C.; Damerau, H.; Garoby, R.; Gilardoni, S.; Goddard, B.; Hancock, S.; Hanke, K.; Lombardi, A.; Mikulec, B.; Raginel, V.; Rumolo, G.; Shaposhnikova, E.; Vretenar, M.

    2012-01-01

    The main upgrades of the injector chain in the framework of the LIU Project will only be implemented in the second long shutdown (LS2), in particular the increase of the PSB-PS transfer energy to 2 GeV or the implementation of cures/solutions against instabilities/e-cloud effects etc. in the SPS. On the other hand, Linac4 will become available by the end of 2014. Until the end of 2015 it may replace Linac2 at short notice, taking 50 MeV protons into the PSB via the existing injection system but with reduced performance. Afterwards, the H - injection equipment will be ready and Linac4 could be connected for 160 MeV H - injection into the PSB during a prolonged winter shutdown before LS2. The anticipated beam performance of the LHC injectors after LS1 in these different cases is presented. Space charge on the PS flat-bottom will remain a limitation because the PSB-PS transfer energy will stay at 1.4 GeV. As a mitigation measure new RF manipulations are presented which can improve brightness for 25 ns bunch spacing, allowing for more than nominal luminosity in the LHC. (authors)

  15. Post LS1 schedule

    CERN Document Server

    Lamont, M

    2014-01-01

    The scheduling limits for a typical long year taking into account technical stops, machine development, spe- cial physics runs are presented. An attempt is then made to outline a ten year post LS1 schedule taking into account the disparate requirements outlined in the previous talks in this session. The demands on the planned long shutdowns and the impact of these demands on their proposed length will be discussed. The option of using ion running as a pre-shutdown cool-down period will be addressed.

  16. Efficient C1-continuous phase-potential upwind (C1-PPU) schemes for coupled multiphase flow and transport with gravity

    Science.gov (United States)

    Jiang, Jiamin; Younis, Rami M.

    2017-10-01

    In the presence of counter-current flow, nonlinear convergence problems may arise in implicit time-stepping when the popular phase-potential upwinding (PPU) scheme is used. The PPU numerical flux is non-differentiable across the co-current/counter-current flow regimes. This may lead to cycles or divergence in the Newton iterations. Recently proposed methods address improved smoothness of the numerical flux. The objective of this work is to devise and analyze an alternative numerical flux scheme called C1-PPU that, in addition to improving smoothness with respect to saturations and phase potentials, also improves the level of scalar nonlinearity and accuracy. C1-PPU involves a novel use of the flux limiter concept from the context of high-resolution methods, and allows a smooth variation between the co-current/counter-current flow regimes. The scheme is general and applies to fully coupled flow and transport formulations with an arbitrary number of phases. We analyze the consistency property of the C1-PPU scheme, and derive saturation and pressure estimates, which are used to prove the solution existence. Several numerical examples for two- and three-phase flows in heterogeneous and multi-dimensional reservoirs are presented. The proposed scheme is compared to the conventional PPU and the recently proposed Hybrid Upwinding schemes. We investigate three properties of these numerical fluxes: smoothness, nonlinearity, and accuracy. The results indicate that in addition to smoothness, nonlinearity may also be critical for convergence behavior and thus needs to be considered in the design of an efficient numerical flux scheme. Moreover, the numerical examples show that the C1-PPU scheme exhibits superior convergence properties for large time steps compared to the other alternatives.

  17. A Modified LS+AR Model to Improve the Accuracy of the Short-term Polar Motion Prediction

    Science.gov (United States)

    Wang, Z. W.; Wang, Q. X.; Ding, Y. Q.; Zhang, J. J.; Liu, S. S.

    2017-03-01

    There are two problems of the LS (Least Squares)+AR (AutoRegressive) model in polar motion forecast: the inner residual value of LS fitting is reasonable, but the residual value of LS extrapolation is poor; and the LS fitting residual sequence is non-linear. It is unsuitable to establish an AR model for the residual sequence to be forecasted, based on the residual sequence before forecast epoch. In this paper, we make solution to those two problems with two steps. First, restrictions are added to the two endpoints of LS fitting data to fix them on the LS fitting curve. Therefore, the fitting values next to the two endpoints are very close to the observation values. Secondly, we select the interpolation residual sequence of an inward LS fitting curve, which has a similar variation trend as the LS extrapolation residual sequence, as the modeling object of AR for the residual forecast. Calculation examples show that this solution can effectively improve the short-term polar motion prediction accuracy by the LS+AR model. In addition, the comparison results of the forecast models of RLS (Robustified Least Squares)+AR, RLS+ARIMA (AutoRegressive Integrated Moving Average), and LS+ANN (Artificial Neural Network) confirm the feasibility and effectiveness of the solution for the polar motion forecast. The results, especially for the polar motion forecast in the 1-10 days, show that the forecast accuracy of the proposed model can reach the world level.

  18. Diagnosis of Elevator Faults with LS-SVM Based on Optimization by K-CV

    Directory of Open Access Journals (Sweden)

    Zhou Wan

    2015-01-01

    Full Text Available Several common elevator malfunctions were diagnosed with a least square support vector machine (LS-SVM. After acquiring vibration signals of various elevator functions, their energy characteristics and time domain indicators were extracted by theoretically analyzing the optimal wavelet packet, in order to construct a feature vector of malfunctions for identifying causes of the malfunctions as input of LS-SVM. Meanwhile, parameters about LS-SVM were optimized by K-fold cross validation (K-CV. After diagnosing deviated elevator guide rail, deviated shape of guide shoe, abnormal running of tractor, erroneous rope groove of traction sheave, deviated guide wheel, and tension of wire rope, the results suggested that the LS-SVM based on K-CV optimization was one of effective methods for diagnosing elevator malfunctions.

  19. Lamb Wave Damage Quantification Using GA-Based LS-SVM

    Directory of Open Access Journals (Sweden)

    Fuqiang Sun

    2017-06-01

    Full Text Available Lamb waves have been reported to be an efficient tool for non-destructive evaluations (NDE for various application scenarios. However, accurate and reliable damage quantification using the Lamb wave method is still a practical challenge, due to the complex underlying mechanism of Lamb wave propagation and damage detection. This paper presents a Lamb wave damage quantification method using a least square support vector machine (LS-SVM and a genetic algorithm (GA. Three damage sensitive features, namely, normalized amplitude, phase change, and correlation coefficient, were proposed to describe changes of Lamb wave characteristics caused by damage. In view of commonly used data-driven methods, the GA-based LS-SVM model using the proposed three damage sensitive features was implemented to evaluate the crack size. The GA method was adopted to optimize the model parameters. The results of GA-based LS-SVM were validated using coupon test data and lap joint component test data with naturally developed fatigue cracks. Cases of different loading and manufacturer were also included to further verify the robustness of the proposed method for crack quantification.

  20. Lamb Wave Damage Quantification Using GA-Based LS-SVM.

    Science.gov (United States)

    Sun, Fuqiang; Wang, Ning; He, Jingjing; Guan, Xuefei; Yang, Jinsong

    2017-06-12

    Lamb waves have been reported to be an efficient tool for non-destructive evaluations (NDE) for various application scenarios. However, accurate and reliable damage quantification using the Lamb wave method is still a practical challenge, due to the complex underlying mechanism of Lamb wave propagation and damage detection. This paper presents a Lamb wave damage quantification method using a least square support vector machine (LS-SVM) and a genetic algorithm (GA). Three damage sensitive features, namely, normalized amplitude, phase change, and correlation coefficient, were proposed to describe changes of Lamb wave characteristics caused by damage. In view of commonly used data-driven methods, the GA-based LS-SVM model using the proposed three damage sensitive features was implemented to evaluate the crack size. The GA method was adopted to optimize the model parameters. The results of GA-based LS-SVM were validated using coupon test data and lap joint component test data with naturally developed fatigue cracks. Cases of different loading and manufacturer were also included to further verify the robustness of the proposed method for crack quantification.

  1. Non-stop training during LS1!

    CERN Multimedia

    HSE Unit

    2013-01-01

    The year 2013 is a busy year for the Safety Training team, who are seeing a dramatic increase in their activities during LS1. The Safety Training Service within the HSE Unit offers training courses all year round to people working on the CERN site who are exposed to a variety of potential hazards (e.g. chemical hazards, fire hazards, etc.) either because of the activities they perform (e.g. work in confined spaces or on machines) and/or their place of work (e.g. workshops, laboratories, underground areas, etc.).   LS1 has triggered an increase in the number of requests for training, mainly from people requiring to carry out work on the LHC. Indeed, in order to access the underground areas, it is obligatory to have taken certain safety courses such as the self-rescue mask or radiation protection training courses. Consequently, the number of training sessions and the number of people trained is currently twice what it was during the same period in 2012, with almost 4,600 people trained in 530 s...

  2. Lindas Leen paštēls, tēls drukātajos medijos un fanu publikās

    OpenAIRE

    Komarovskis, Jānis

    2011-01-01

    Bakalaura darba tēma ir „Lindas Leen paštēls, tēls drukātajos medijos un fanu publikās”. Darba mērķis ir izpētīt Lindas Leen paštēlu, tēlu drukātajos medijos un fanu publikās. Darba teorētiskā daļa balstās uz Klausa Mertena (Klaus Merten) tēla veidošanās teoriju, kura apgalvo, ka tēla veidošanās auditorijas uztverē ir cieši saistīta ar medijos publicēto informāciju par noteikto objektu. Pētījuma veikšanai ir izmantotas četras pētniecības metodes: daļēji strukturētā intervija, mediju kon...

  3. Comparison of central corneal thickness measured by Lenstar LS900, OrbscanⅡ and ultrasonic pachmetry

    Directory of Open Access Journals (Sweden)

    Hong-Tao Zhang

    2013-09-01

    Full Text Available AIM: To investigate the difference of central corneal thickness(CCTmeasured by Lenstar LS900, OrbscahⅡ system and ultrasonic pachmetry, and to evaluate the correlation and consistency of the results for providing a theoretical basis for clinical application.METHODS: The mean value of CCT in 70 eyes of 35 patients measured three times by Lenstar LS900, OrbscahⅡ system and ultrasonic pachmetry underwent statistical analysis. The difference of CCT was compared, and the correlation and consistency of three measurements were analyzed to provide theoretical basis for clinical application. CCT values measured by different methods were analyzed with randomized block variance analysis. LSD-t test was used for pairwise comparison between groups. The correlation of three measurement methods were analyzed by linear correlation analysis, and Bland-Altman was used to analyze the consistency.RESULTS: The mean CCT values measured by Lenstar LS900, OrbscanⅡ and ultrasonic pachmetry were 542.75±40.06, 528.74±39.59, 538.54±40.93μm, respectively. The mean difference of CCT measurement was 4.21±8.78μm between Lenstar LS900 and ultrasonic pachmetry, 14.01±13.39μm between Lenstar LS900 and Orbscan Ⅱ, 9.8±10.57μm between ultrasonic pachmetry and Orbscan Ⅱ. The difference was statistically significant(PP>0.05: There was positive correlation between CCT with Lenstar LS900 and ultrasonic pachmetry(r=0.977, 0.944; PCONCLUSION: There are excellent correlation among Lenstar LS900, Orbscan Ⅱ and ultrasonic pachmetry. Lenstar LS900 can be used as CCT non-contact measurement tool.

  4. Lag synchronization of unknown chaotic delayed Yang-Yang-type fuzzy neural networks with noise perturbation based on adaptive control and parameter identification.

    Science.gov (United States)

    Xia, Yonghui; Yang, Zijiang; Han, Maoan

    2009-07-01

    This paper considers the lag synchronization (LS) issue of unknown coupled chaotic delayed Yang-Yang-type fuzzy neural networks (YYFCNN) with noise perturbation. Separate research work has been published on the stability of fuzzy neural network and LS issue of unknown coupled chaotic neural networks, as well as its application in secure communication. However, there have not been any studies that integrate the two. Motivated by the achievements from both fields, we explored the benefits of integrating fuzzy logic theories into the study of LS problems and applied the findings to secure communication. Based on adaptive feedback control techniques and suitable parameter identification, several sufficient conditions are developed to guarantee the LS of coupled chaotic delayed YYFCNN with or without noise perturbation. The problem studied in this paper is more general in many aspects. Various problems studied extensively in the literature can be treated as special cases of the findings of this paper, such as complete synchronization (CS), effect of fuzzy logic, and noise perturbation. This paper presents an illustrative example and uses simulated results of this example to show the feasibility and effectiveness of the proposed adaptive scheme. This research also demonstrates the effectiveness of application of the proposed adaptive feedback scheme in secure communication by comparing chaotic masking with fuzziness with some previous studies. Chaotic signal with fuzziness is more complex, which makes unmasking more difficult due to the added fuzzy logic.

  5. Efficient decoupling schemes with bounded controls based on Eulerian orthogonal arrays

    International Nuclear Information System (INIS)

    Wocjan, Pawel

    2006-01-01

    The task of decoupling, i.e., removing unwanted internal couplings of a quantum system and its couplings to an environment, plays an important role in quantum control theory. There are many efficient decoupling schemes based on combinatorial concepts such as orthogonal arrays, difference schemes, and Hadamard matrices. So far these combinatorial decoupling schemes have relied on the ability to effect sequences of instantaneous, arbitrarily strong control Hamiltonians (bang-bang controls). To overcome the shortcomings of bang-bang control, Viola and Knill proposed a method called 'Eulerian decoupling' that allows the use of bounded-strength controls for decoupling. However, their method was not directly designed to take advantage of the local structure of internal couplings and couplings to an environment that typically occur in multipartite quantum systems. In this paper we define a combinatorial structure called Eulerian orthogonal array. It merges the desirable properties of orthogonal arrays and Eulerian cycles in Cayley graphs (that are the basis of Eulerian decoupling). We show that this structure gives rise to decoupling schemes with bounded-strength control Hamiltonians that can be used to remove both internal couplings and couplings to an environment of a multipartite quantum system. Furthermore, we show how to construct Eulerian orthogonal arrays having good parameters in order to obtain efficient decoupling schemes

  6. A Cell-Centered Multiphase ALE Scheme With Structural Coupling

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, Timothy Alan [Univ. of California, Davis, CA (United States)

    2012-04-16

    A novel computational scheme has been developed for simulating compressible multiphase flows interacting with solid structures. The multiphase fluid is computed using a Godunov-type finite-volume method. This has been extended to allow computations on moving meshes using a direct arbitrary-Eulerian- Lagrangian (ALE) scheme. The method has been implemented within a Lagrangian hydrocode, which allows modeling the interaction with Lagrangian structural regions. Although the above scheme is general enough for use on many applications, the ultimate goal of the research is the simulation of heterogeneous energetic material, such as explosives or propellants. The method is powerful enough for application to all stages of the problem, including the initial burning of the material, the propagation of blast waves, and interaction with surrounding structures. The method has been tested on a number of canonical multiphase tests as well as fluid-structure interaction problems.

  7. [Measurement of soil organic matter and available K based on SPA-LS-SVM].

    Science.gov (United States)

    Zhang, Hai-Liang; Liu, Xue-Mei; He, Yong

    2014-05-01

    Visible and short wave infrared spectroscopy (Vis/SW-NIRS) was investigated in the present study for measurement of soil organic matter (OM) and available potassium (K). Four types of pretreatments including smoothing, SNV, MSC and SG smoothing+first derivative were adopted to eliminate the system noises and external disturbances. Then partial least squares regression (PLSR) and least squares-support vector machine (LS-SVM) models were implemented for calibration models. The LS-SVM model was built by using characteristic wavelength based on successive projections algorithm (SPA). Simultaneously, the performance of LSSVM models was compared with PLSR models. The results indicated that LS-SVM models using characteristic wavelength as inputs based on SPA outperformed PLSR models. The optimal SPA-LS-SVM models were achieved, and the correlation coefficient (r), and RMSEP were 0. 860 2 and 2. 98 for OM and 0. 730 5 and 15. 78 for K, respectively. The results indicated that visible and short wave near infrared spectroscopy (Vis/SW-NIRS) (325 approximately 1 075 nm) combined with LS-SVM based on SPA could be utilized as a precision method for the determination of soil properties.

  8. GIS-based Analysis of LS Factor under Coal Mining Subsidence Impacts in Sandy Region

    Directory of Open Access Journals (Sweden)

    W. Xiao

    2014-09-01

    Full Text Available Coal deposits in the adjacent regions of Shanxi, Shaanxi, and Inner Mongolia province (SSI account for approximately two-thirds of coal in China; therefore, the SSI region has become the frontier of coal mining and its westward movement. Numerous adverse impacts to land and environment have arisen in these sandy, arid, and ecologically fragile areas. Underground coal mining activities cause land to subside and subsequent soil erosion, with slope length and slope steepness (LS as the key influential factor. In this investigation, an SSI mining site was chosen as a case study area, and 1 the pre-mining LS factor was obtained using a digital elevation model (DEM dataset; 2 a mining subsidence prediction was implemented with revised subsidence prediction factors; and 3 the post-mining LS factor was calculated by integrating the pre-mining DEM dataset and coal mining subsidence prediction data. The results revealed that the LS factor leads to some changes in the bottom of subsidence basin and considerable alterations at the basin’s edges of basin. Moreover, the LS factor became larger in the steeper terrain under subsidence impacts. This integrated method could quantitatively analyse LS changes and spatial distribution under mining impacts, which will benefit and provide references for soil erosion evaluations in this region

  9. Characteristics of CdLS (Cornelia de Lange Syndrome)

    Science.gov (United States)

    ... Celebration and Memorial Gifts Planned Giving Monthly Giving Corporate Partnership Matching Gifts Stocks, Trusts and Other Gifts ... 25 percent of individuals with CdLS. Behavioral and communication issues and developmental delays often exist. Major Characteristics ...

  10. A new 4π(LS)-γ coincidence counter at NCBJ RC POLATOM with TDCR detector in the beta channel.

    Science.gov (United States)

    Ziemek, T; Jęczmieniowski, A; Cacko, D; Broda, R; Lech, E

    2016-03-01

    A new 4π(LS)-γ coincidence system (TDCRG) was built at the NCBJ RC POLATOM. The counter consists of a TDCR detector in the beta channel and scintillation detector with NaI(Tl) crystal in the gamma channel. The system is equipped with a digital board with FPGA, which records and analyses coincidences in the TDCR detector and coincidences between the beta and gamma channels. The characteristics of the system and a scheme of the FPGA implementation with behavioral simulation are given. The TDCRG counter was validated by activity measurements on (14)C and (60)Co solutions standardized in RC POLATOM using previously validated methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Summary of sessions 5 and 6: long shutdown 1 (LS1) 2013-2014

    International Nuclear Information System (INIS)

    Bordry, F.; Foraz, K.

    2012-01-01

    The minimal duration for LS1 is 20 months, meaning the time from physics to physics will be about 2 years. The actual start of LS1 is set for the 17. November 2012, which will allow the Liquid Helium emptying from the machine before Christmas. However, delivery dates for certain components are on the critical path of the experiments, which will allow the first beams for beam commissioning not before September 2014. Depending on the results of mid-2012 physics, the start date of LS1 will be reviewed. The actual plan for injectors is in line with the LHC plan, but the risk of running injectors for two years has to be assessed. The analysis of resources is progressing well throughout the complex (collaborations and internal mobility) and is being done according to priorities. Certain activities have already been postponed to LS2, and new requests will be carefully analyzed, as well as open issues

  12. A generalized scheme for designing multistable continuous ...

    Indian Academy of Sciences (India)

    In this paper, a generalized scheme is proposed for designing multistable continuous dynamical systems. The scheme is based on the concept of partial synchronization of states and the concept of constants of motion. The most important observation is that by coupling two mdimensional dynamical systems, multistable ...

  13. Cellular prion protein and γ-synuclein overexpression in LS 174T colorectal cancer cell drives endothelial proliferation-to-differentiation switch

    Directory of Open Access Journals (Sweden)

    Sing-Hui Ong

    2018-03-01

    Full Text Available Background Tumor-induced angiogenesis is an imperative event in pledging new vasculature for tumor metastasis. Since overexpression of neuronal proteins gamma-synuclein (γ-Syn and cellular prion protein (PrPC is always detected in advanced stages of cancer diseases which involve metastasis, this study aimed to investigate whether γ-Syn or PrPC overexpression in colorectal adenocarcinoma, LS 174T cells affects angiogenesis of endothelial cells, EA.hy 926 (EA. Methods EA cells were treated with conditioned media (CM of LS 174T-γ-Syn or LS 174T-PrP, and their proliferation, invasion, migration, adhesion and ability to form angiogenic tubes were assessed using a range of biological assays. To investigate plausible background mechanisms in conferring the properties of EA cells above, nitrite oxide (NO levels were measured and the expression of angiogenesis-related factors was assessed using a human angiogenesis antibody array. Results EA proliferation was significantly inhibited by LS 174T-PrP CM whereas its telomerase activity was reduced by CM of LS 174T-γ-Syn or LS 174T-PrP, as compared to EA incubated with LS 174T CM. Besides, LS 174T-γ-Syn CM or LS 174T-PrP CM inhibited EA invasion and migration in Boyden chamber assay. Furthermore, LS 174T-γ-Syn CM significantly inhibited EA migration in scratch wound assay. Gelatin zymography revealed reduced secretion of MMP-2 and MMP-9 by EA treated with LS 174T-γ-Syn CM or LS 174T-PrP CM. In addition, cell adhesion assay showed lesser LS 174T-γ-Syn or LS 174T-PrP cells adhered onto EA, as compared to LS 174T. In tube formation assay, LS 174T-γ-Syn CM or LS 174T-PrP CM induced EA tube formation. Increased NO secretion by EA treated with LS 174T-γ-Syn CM or LS 174T-PrP CM was also detected. Lastly, decreased expression of pro-angiogenic factors like CXCL16, IGFBP-2 and amphiregulin in LS 174T-γ-Syn CM or LS 174T-PrP CM was detected using the angiogenesis antibody array. Discussion These results

  14. Experimental and Analytical Studies on Improved Feedforward ML Estimation Based on LS-SVR

    Directory of Open Access Journals (Sweden)

    Xueqian Liu

    2013-01-01

    Full Text Available Maximum likelihood (ML algorithm is the most common and effective parameter estimation method. However, when dealing with small sample and low signal-to-noise ratio (SNR, threshold effects are resulted and estimation performance degrades greatly. It is proved that support vector machine (SVM is suitable for small sample. Consequently, we employ the linear relationship between least squares support vector regression (LS-SVR’s inputs and outputs and regard LS-SVR process as a time-varying linear filter to increase input SNR of received signals and decrease the threshold value of mean square error (MSE curve. Furthermore, it is verified that by taking single-tone sinusoidal frequency estimation, for example, and integrating data analysis and experimental validation, if LS-SVR’s parameters are set appropriately, not only can the LS-SVR process ensure the single-tone sinusoid and additive white Gaussian noise (AWGN channel characteristics of original signals well, but it can also improves the frequency estimation performance. During experimental simulations, LS-SVR process is applied to two common and representative single-tone sinusoidal ML frequency estimation algorithms, the DFT-based frequency-domain periodogram (FDP and phase-based Kay ones. And the threshold values of their MSE curves are decreased by 0.3 dB and 1.2 dB, respectively, which obviously exhibit the advantage of the proposed algorithm.

  15. LS1 Report: nearing the finish line

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    The LS1 team will be popping the champagne next week, on Tuesday 27 May, celebrating the completion of the consolidation of the splices in the framework of the SMACC project.   A technician works on one of the final shunts during LS1. "It has been a long journey into the heart of the LHC, tackling over 27,000 shunts*," says Luca Bottura, TE-MSC Group leader. "We are happy that the final train has, at last, reached its rest station, and look forward to sending it on many new adventures," confirm Frédéric Savary, TE-MSC Large Magnet Facility Section leader, and Jean-Philippe Tock, SMACC Project leader. Also in the LHC, pressure tests in Sector 1-2 - the third sector to be tackled - are almost complete. The temperature in Sector 6-7 is around 100K and it will be accessible again from next week. As for the SPS, all the LSS1 beam elements excluding one monitor are back in position. Vacuum teams are now ...

  16. CMS DAQ current and future hardware upgrades up to post Long Shutdown 3 (LS3) times

    CERN Document Server

    Racz, Attila; Behrens, Ulf; Branson, James; Chaze, Olivier; Cittolin, Sergio; Contescu, Cristian; da Silva Gomes, Diego; Darlea, Georgiana-Lavinia; Deldicque, Christian; Demiragli, Zeynep; Dobson, Marc; Doualot, Nicolas; Erhan, Samim; Fulcher, Jonathan Richard; Gigi, Dominique; Gladki, Maciej; Glege, Frank; Gomez-Ceballos, Guillelmo; Hegeman, Jeroen; Holzner, Andre; Janulis, Mindaugas; Lettrich, Michael; Meijers, Frans; Meschi, Emilio; Mommsen, Remigius K; Morovic, Srecko; O'Dell, Vivian; Orn, Samuel Johan; Orsini, Luciano; Papakrivopoulos, Ioannis; Paus, Christoph; Petrova, Petia; Petrucci, Andrea; Pieri, Marco; Rabady, Dinyar; Reis, Thomas; Sakulin, Hannes; Schwick, Christoph; Simelevicius, Dainius; Vazquez Velez, Cristina; Vougioukas, Michail; Zejdl, Petr

    2017-01-01

    Following the first LHC collisions seen and recorded by CMS in 2009, the DAQ hardware went through a major upgrade during LS1 (2013- 2014) and new detectors have been connected during 2015-2016 and 2016-2017 winter shutdowns. Now, LS2 (2019-2020) and LS3 (2024-mid 2026) are actively being prepared. This paper shows how CMS DAQ hardware has evolved from the beginning and will continue to evolve in order to meet the future challenges posed by High Luminosity LHC (HL-LHC) and the CMS detector evolution. In particular, post LS3 DAQ architectures are focused upon.

  17. Can the proton injectors meet the HL-LHC requirements after LS2?

    International Nuclear Information System (INIS)

    Goddard, B.; Bartosik, H.; Bracco, C.; Bruening, O.; Carli, C.; Cornelis, K.; Damerau, H.; Garoby, R.; Gilardoni, S.; Hancock, S.; Hanke, K.; Kain, V.; Meddahi, M.; Mikulec, B.; Papaphilippou, Y.; Rumolo, G.; Shaposhnikova, E.; Steerenberg, R.; Vretenar, M.

    2012-01-01

    The LIU project has as mandate the upgrade of the LHC injector chain to match the requirements of HL-LHC. The present planning assumes that the upgrade work will be completed in LS2, for commissioning in the following operational year. The known limitations in the different injectors are described, together with the various upgrades planned to improve the performance. The expected performance reach after the upgrade with 25 and 50 ns beams is examined. The project planning is discussed in view of the present LS1 and LS2 planning. The main unresolved questions and associated decision points are presented, and the key issues to be addressed by the end of 2012 are detailed in the context of the machine development programs and hardware construction activities. (authors)

  18. An efficient coupled polynomial interpolation scheme to eliminate material-locking in the Euler-Bernoulli piezoelectric beam finite element

    Directory of Open Access Journals (Sweden)

    Litesh N. Sulbhewar

    Full Text Available The convergence characteristic of the conventional two-noded Euler-Bernoulli piezoelectric beam finite element depends on the configuration of the beam cross-section. The element shows slower convergence for the asymmetric material distribution in the beam cross-section due to 'material-locking' caused by extension-bending coupling. Hence, the use of conventional Euler-Bernoulli beam finite element to analyze piezoelectric beams which are generally made of the host layer with asymmetrically surface bonded piezoelectric layers/patches, leads to increased computational effort to yield converged results. Here, an efficient coupled polynomial interpolation scheme is proposed to improve the convergence of the Euler-Bernoulli piezoelectric beam finite elements, by eliminating ill-effects of material-locking. The equilibrium equations, derived using a variational formulation, are used to establish relationships between field variables. These relations are used to find a coupled quadratic polynomial for axial displacement, having contributions from an assumed cubic polynomial for transverse displacement and assumed linear polynomials for layerwise electric potentials. A set of coupled shape functions derived using these polynomials efficiently handles extension-bending and electromechanical couplings at the field interpolation level itself in a variationally consistent manner, without increasing the number of nodal degrees of freedom. The comparison of results obtained from numerical simulation of test problems shows that the convergence characteristic of the proposed element is insensitive to the material configuration of the beam cross-section.

  19. Biases and statistical errors in Monte Carlo burnup calculations: an unbiased stochastic scheme to solve Boltzmann/Bateman coupled equations

    International Nuclear Information System (INIS)

    Dumonteil, E.; Diop, C.M.

    2011-01-01

    External linking scripts between Monte Carlo transport codes and burnup codes, and complete integration of burnup capability into Monte Carlo transport codes, have been or are currently being developed. Monte Carlo linked burnup methodologies may serve as an excellent benchmark for new deterministic burnup codes used for advanced systems; however, there are some instances where deterministic methodologies break down (i.e., heavily angularly biased systems containing exotic materials without proper group structure) and Monte Carlo burn up may serve as an actual design tool. Therefore, researchers are also developing these capabilities in order to examine complex, three-dimensional exotic material systems that do not contain benchmark data. Providing a reference scheme implies being able to associate statistical errors to any neutronic value of interest like k(eff), reaction rates, fluxes, etc. Usually in Monte Carlo, standard deviations are associated with a particular value by performing different independent and identical simulations (also referred to as 'cycles', 'batches', or 'replicas'), but this is only valid if the calculation itself is not biased. And, as will be shown in this paper, there is a bias in the methodology that consists of coupling transport and depletion codes because Bateman equations are not linear functions of the fluxes or of the reaction rates (those quantities being always measured with an uncertainty). Therefore, we have to quantify and correct this bias. This will be achieved by deriving an unbiased minimum variance estimator of a matrix exponential function of a normal mean. The result is then used to propose a reference scheme to solve Boltzmann/Bateman coupled equations, thanks to Monte Carlo transport codes. Numerical tests will be performed with an ad hoc Monte Carlo code on a very simple depletion case and will be compared to the theoretical results obtained with the reference scheme. Finally, the statistical error propagation

  20. A New Scheme for the Simulation of Microscale Flow and Dispersion in Urban Areas by Coupling Large-Eddy Simulation with Mesoscale Models

    Science.gov (United States)

    Li, Haifeng; Cui, Guixiang; Zhang, Zhaoshun

    2018-04-01

    A coupling scheme is proposed for the simulation of microscale flow and dispersion in which both the mesoscale field and small-scale turbulence are specified at the boundary of a microscale model. The small-scale turbulence is obtained individually in the inner and outer layers by the transformation of pre-computed databases, and then combined in a weighted sum. Validation of the results of a flow over a cluster of model buildings shows that the inner- and outer-layer transition height should be located in the roughness sublayer. Both the new scheme and the previous scheme are applied in the simulation of the flow over the central business district of Oklahoma City (a point source during intensive observation period 3 of the Joint Urban 2003 experimental campaign), with results showing that the wind speed is well predicted in the canopy layer. Compared with the previous scheme, the new scheme improves the prediction of the wind direction and turbulent kinetic energy (TKE) in the canopy layer. The flow field influences the scalar plume in two ways, i.e. the averaged flow field determines the advective flux and the TKE field determines the turbulent flux. Thus, the mean, root-mean-square and maximum of the concentration agree better with the observations with the new scheme. These results indicate that the new scheme is an effective means of simulating the complex flow and dispersion in urban canopies.

  1. Nonlinear Time Series Prediction Using LS-SVM with Chaotic Mutation Evolutionary Programming for Parameter Optimization

    International Nuclear Information System (INIS)

    Xu Ruirui; Chen Tianlun; Gao Chengfeng

    2006-01-01

    Nonlinear time series prediction is studied by using an improved least squares support vector machine (LS-SVM) regression based on chaotic mutation evolutionary programming (CMEP) approach for parameter optimization. We analyze how the prediction error varies with different parameters (σ, γ) in LS-SVM. In order to select appropriate parameters for the prediction model, we employ CMEP algorithm. Finally, Nasdaq stock data are predicted by using this LS-SVM regression based on CMEP, and satisfactory results are obtained.

  2. Scheme for realizing quantum computation and quantum information transfer with superconducting qubits coupling to a 1D transmission line resonator

    International Nuclear Information System (INIS)

    Zhen-Gang, Shi; Xiong-Wen, Chen; Xi-Xiang, Zhu; Ke-Hui, Song

    2009-01-01

    This paper proposes a simple scheme for realizing one-qubit and two-qubit quantum gates as well as multiqubit entanglement based on dc-SQUID charge qubits through the control of their coupling to a 1D transmission line resonator (TLR). The TLR behaves effectively as a quantum data-bus mode of a harmonic oscillator, which has several practical advantages including strong coupling strength, reproducibility, immunity to 1/f noise, and suppressed spontaneous emission. In this protocol, the data-bus does not need to stay adiabatically in its ground state, which results in not only fast quantum operation, but also high-fidelity quantum information processing. Also, it elaborates the transfer process with the 1D transmission line. (general)

  3. Effects of multilayer snow scheme on the simulation of snow: Offline Noah and coupled with NCEP CFSv2

    Science.gov (United States)

    Saha, Subodh Kumar; Sujith, K.; Pokhrel, Samir; Chaudhari, Hemantkumar S.; Hazra, Anupam

    2017-03-01

    The Noah version 2.7.1 is a moderately complex land surface model (LSM), with a single layer snowpack, combined with vegetation and underlying soil layer. Many previous studies have pointed out biases in the simulation of snow, which may hinder the skill of a forecasting system coupled with the Noah. In order to improve the simulation of snow by the Noah, a multilayer snow scheme (up to a maximum of six layers) is introduced. As Noah is the land surface component of the Climate Forecast System version 2 (CFSv2) of the National Centers for Environmental Prediction (NCEP), the modified Noah is also coupled with the CFSv2. The offline LSM shows large improvements in the simulation of snow depth, snow water equivalent (SWE), and snow cover area during snow season (October to June). CFSv2 with the modified Noah reveals a dramatic improvements in the simulation of snow depth and 2 m air temperature and moderate improvements in SWE. As suggested in the previous diagnostic and sensitivity study, improvements in the simulation of snow by CFSv2 have lead to the reduction in dry bias over the Indian subcontinent (by a maximum of 2 mm d-1). The multilayer snow scheme shows promising results in the simulation of snow as well as Indian summer monsoon rainfall and hence this development may be the part of the future version of the CFS.

  4. Synchronization of hyperchaotic oscillators via single unidirectional chaotic-coupling

    International Nuclear Information System (INIS)

    Zou Yanli; Zhu Jie; Chen Guanrong; Luo Xiaoshu

    2005-01-01

    In this paper, synchronization of two hyperchaotic oscillators via a single variable's unidirectional coupling is studied. First, the synchronizability of the coupled hyperchaotic oscillators is proved mathematically. Then, the convergence speed of this synchronization scheme is analyzed. In order to speed up the response with a relatively large coupling strength, two kinds of chaotic coupling synchronization schemes are proposed. In terms of numerical simulations and the numerical calculation of the largest conditional Lyapunov exponent, it is shown that in a given range of coupling strengths, chaotic-coupling synchronization is quicker than the typical continuous-coupling synchronization. Furthermore, A circuit realization based on the chaotic synchronization scheme is designed and Pspice circuit simulation validates the simulated hyperchaos synchronization mechanism

  5. The spin-orbit interaction and SU(3) generators in superdeformation

    Energy Technology Data Exchange (ETDEWEB)

    Sugawara-Tanabe, K [School of Social Information, Otsuma Women` s University, Tokyo (Japan); Arima, A [Tokyo Univ. (Japan). Dept. of Physics

    1992-08-01

    The authors found that the effect of spin-orbit coupling becomes smaller for the parity doublet level and for some other levels around superdeformation. This is because of the strongly deformed quadrupole field, which indicates the L-S coupling scheme is recovered for these levels. These levels can be described by an SU-3 group with eight generators and a Casimir operator. 6 refs., 3 figs.

  6. LS1 Report: Handing in the ATLAS keys

    CERN Multimedia

    Antonella Del Rosso, Katarina Anthony

    2014-01-01

    After completing more than 250 work packages concerning the whole detector and experimental site, the ATLAS and CERN teams involved with LS1 operations are now wrapping things up before starting the commissioning phase in preparation for the LHC restart. The giant detector is now more efficient, safer and even greener than ever thanks to the huge amount of work carried out over the past two years.   Cleaning up the ATLAS cavern and detector in preparation for Run 2. Hundreds of people, more than 3000 certified interventions, huge and delicate parts of the detector completely refurbished: the ATLAS detector that will take data during Run 2 is a brand new machine, which will soon be back in the hands of the thousands of scientists who are preparing for the high-energy run of the LHC accelerator. “During LS1, we have upgraded the detector’s basic infrastructure and a few of its sub-detectors,” explains Beniamino Di Girolamo, ATLAS Technical Coordinator. &...

  7. Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.)

    Science.gov (United States)

    Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan

    2018-01-01

    Lettuce (Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce. PMID:29403510

  8. Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan

    2017-01-01

    Lettuce ( Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce.

  9. A hybrid Lagrangian Voronoi-SPH scheme

    Science.gov (United States)

    Fernandez-Gutierrez, D.; Souto-Iglesias, A.; Zohdi, T. I.

    2017-11-01

    A hybrid Lagrangian Voronoi-SPH scheme, with an explicit weakly compressible formulation for both the Voronoi and SPH sub-domains, has been developed. The SPH discretization is substituted by Voronoi elements close to solid boundaries, where SPH consistency and boundary conditions implementation become problematic. A buffer zone to couple the dynamics of both sub-domains is used. This zone is formed by a set of particles where fields are interpolated taking into account SPH particles and Voronoi elements. A particle may move in or out of the buffer zone depending on its proximity to a solid boundary. The accuracy of the coupled scheme is discussed by means of a set of well-known verification benchmarks.

  10. A scheme for designing extreme multistable discrete dynamical ...

    Indian Academy of Sciences (India)

    A scheme for designing extreme multistable discrete dynamical systems ... Abstract. In this paper, we propose a scheme for designing discrete extreme multistable systems coupling two identical dynamical systems. Existence ... Department of Applied Mathematics, University of Calcutta, 92 APC Road, Kolkata 700 009, India ...

  11. Controllable coupling of distributed qubits within a microtoroidal cavity network

    Science.gov (United States)

    Hu, C.; Xia, Y.; Song, J.

    2012-05-01

    We propose a scheme to control the coupling between two arbitrary atoms scattered within a quantum network composed of microtoroidal cavities linked by a ring-fibre. The atom-atom effective couplings are induced by pairing of off-resonant Raman transitions. The couplings can be arbitrarily controlled by adjusting classical fields. Compared with the previous scheme [S.B. Zheng, C.P. Yang, F. Nori, Phys. Rev. A 82, 042327 (2010)], the present scheme uses microtoroidal cavities with higher coupling efficiency than Fabry-Perot cavities. Furthermore, the scheme is not only suitable for the short-fibre limit, but also for multiple fibre modes. The added fibre modes can play a positive role, especially when the coupling rate between cavity-mode and fibre-mode is not large. In addition, a wider frequency domain of fibre modes can be used in this scheme.

  12. Calculation of “LS-curves” for coincidence summing corrections in gamma ray spectrometry

    Science.gov (United States)

    Vidmar, Tim; Korun, Matjaž

    2006-01-01

    When coincidence summing correction factors for extended samples are calculated in gamma-ray spectrometry from full-energy-peak and total efficiencies, their variation over the sample volume needs to be considered. In other words, the correction factors cannot be computed as if the sample were a point source. A method developed by Blaauw and Gelsema takes the variation of the efficiencies over the sample volume into account. It introduces the so-called LS-curve in the calibration procedure and only requires the preparation of a single standard for each sample geometry. We propose to replace the standard preparation by calculation and we show that the LS-curves resulting from our method yield coincidence summing correction factors that are consistent with the LS values obtained from experimental data.

  13. Steady Modeling for an Ammonia Synthesis Reactor Based on a Novel CDEAS-LS-SVM Model

    Directory of Open Access Journals (Sweden)

    Zhuoqian Liu

    2014-01-01

    Full Text Available A steady-state mathematical model is built in order to represent plant behavior under stationary operating conditions. A novel modeling using LS-SVR based on Cultural Differential Evolution with Ant Search is proposed. LS-SVM is adopted to establish the model of the net value of ammonia. The modeling method has fast convergence speed and good global adaptability for identification of the ammonia synthesis process. The LS-SVR model was established using the above-mentioned method. Simulation results verify the validity of the method.

  14. A low-order coupled chemistry meteorology model for testing online and offline data assimilation schemes: L95-GRS (v1.0)

    Science.gov (United States)

    Haussaire, J.-M.; Bocquet, M.

    2016-01-01

    Bocquet and Sakov (2013) introduced a low-order model based on the coupling of the chaotic Lorenz-95 (L95) model, which simulates winds along a mid-latitude circle, with the transport of a tracer species advected by this zonal wind field. This model, named L95-T, can serve as a playground for testing data assimilation schemes with an online model. Here, the tracer part of the model is extended to a reduced photochemistry module. This coupled chemistry meteorology model (CCMM), the L95-GRS (generic reaction set) model, mimics continental and transcontinental transport and the photochemistry of ozone, volatile organic compounds and nitrogen oxides. Its numerical implementation is described. The model is shown to reproduce the major physical and chemical processes being considered. L95-T and L95-GRS are specifically designed and useful for testing advanced data assimilation schemes, such as the iterative ensemble Kalman smoother (IEnKS), which combines the best of ensemble and variational methods. These models provide useful insights prior to the implementation of data assimilation methods into larger models. We illustrate their use with data assimilation schemes on preliminary yet instructive numerical experiments. In particular, online and offline data assimilation strategies can be conveniently tested and discussed with this low-order CCMM. The impact of observed chemical species concentrations on the wind field estimate can be quantitatively assessed. The impacts of the wind chaotic dynamics and of the chemical species non-chaotic but highly nonlinear dynamics on the data assimilation strategies are illustrated.

  15. LevelScheme: A level scheme drawing and scientific figure preparation system for Mathematica

    Science.gov (United States)

    Caprio, M. A.

    2005-09-01

    LevelScheme is a scientific figure preparation system for Mathematica. The main emphasis is upon the construction of level schemes, or level energy diagrams, as used in nuclear, atomic, molecular, and hadronic physics. LevelScheme also provides a general infrastructure for the preparation of publication-quality figures, including support for multipanel and inset plotting, customizable tick mark generation, and various drawing and labeling tasks. Coupled with Mathematica's plotting functions and powerful programming language, LevelScheme provides a flexible system for the creation of figures combining diagrams, mathematical plots, and data plots. Program summaryTitle of program:LevelScheme Catalogue identifier:ADVZ Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVZ Operating systems:Any which supports Mathematica; tested under Microsoft Windows XP, Macintosh OS X, and Linux Programming language used:Mathematica 4 Number of bytes in distributed program, including test and documentation:3 051 807 Distribution format:tar.gz Nature of problem:Creation of level scheme diagrams. Creation of publication-quality multipart figures incorporating diagrams and plots. Method of solution:A set of Mathematica packages has been developed, providing a library of level scheme drawing objects, tools for figure construction and labeling, and control code for producing the graphics.

  16. R-matrix calculations for electron-impact excitation of C(+), N(2+), and O(3+) including fine structure

    Science.gov (United States)

    Luo, D.; Pradhan, A. K.

    1990-01-01

    The new R-matrix package for comprehensive close-coupling calculations for electron scattering with the first three ions in the boron isoelectronic sequence, the astrophysically significant C(+), N(2+), and O(3+), is presented. The collision strengths are calculated in the LS coupling approximation, as well as in pair-coupling scheme, for the transitions among the fine-structure sublevels. Calculations are carried out at a large number of energies in order to study the detailed effects of autoionizing resonances.

  17. Detector Plans for LS1

    Energy Technology Data Exchange (ETDEWEB)

    Nessi, M [European Organization for Nuclear Research, Geneva (Switzerland)

    2012-07-01

    All experiments plan an effective usage of the LS1 shutdown period. After three years of running they will go through a consolidation phase, mostly to fix problems that have emerged over time, like single points of failure in the infrastructure, failures of low voltage power supplies and optical links. Upgrades of some detector components will start, mainly related to the beam pipe, the innermost tracker elements and the trigger system. Detector components, which had to be staged for cost reasons in 2003, will then enter into the detector setup. The goal is to be fully ready for the new energy regime at nominal luminosity.

  18. Launch of new e-learning course “Safety during LS1”

    CERN Multimedia

    HSE Unit

    2013-01-01

    After 3 years of activity, the LHC and the rest of the accelerator chain have been shut down for about 2 years (from February 2013 to December 2014) due to maintenance and upgrade work, on the surface as well as underground.   CERN has developed a new e-learning course related to this Long Shutdown period (LS1) so as to provide all the collaborators working in the LS1 area with accurate security-oriented information. The objectives of this new course are to: Present LS1 and its context, Identify CERN facilities’ major risks, Identify the main risks associated with our co-activities, Explain how safety issues are being handled at CERN, Present all the basic safety measures to be respected, Present all emergency and rescue instructions. The course is available via the e-learning SIR application. It is compulsory for all newcomers at CERN, along with the “CERN Safety Introduction” training. It is also highly recommended that people who were already w...

  19. Cluster synchronization in community network with hybrid coupling

    International Nuclear Information System (INIS)

    Yang, Lixin; Jiang, Jun; Liu, Xiaojun

    2016-01-01

    Highlights: • A community network model with hybrid coupling is proposed. • Control scheme is designed via combining adaptive external coupling strength and feedback control. • The influence of topology structure on synchronization of community network is discussed. - Abstract: A general model of community network with hybrid coupling is proposed in this paper. In the community network model with hybrid coupling, the inner connections are in the same type of coupling within the same community and in different types of coupling in different communities. The connections between different pair of communities are also nonidentical. Cluster synchronization of community network with hybrid coupling is investigated via adaptive couplings control scheme. Effective controllers are designed for constructing an effective control scheme and adjusting automatically the adaptive external coupling strength by taking external coupling strength as adaptive variables on a small fraction of network edges. Moreover, the impact of the topology on the synchronizability of community network is investigated. The numerical results reveal that the number of links between communities and the degree of the connector nodes have significant effects on the synchronization performance.

  20. Obtaining the Electron Angular Momentum Coupling Spectroscopic Terms, jj

    Science.gov (United States)

    Orofino, Hugo; Faria, Roberto B.

    2010-01-01

    A systematic procedure is developed to obtain the electron angular momentum coupling (jj) spectroscopic terms, which is based on building microstates in which each individual electron is placed in a different m[subscript j] "orbital". This approach is similar to that used to obtain the spectroscopic terms under the Russell-Saunders (LS) coupling…

  1. Efficient Scheme for Chemical Flooding Simulation

    Directory of Open Access Journals (Sweden)

    Braconnier Benjamin

    2014-07-01

    Full Text Available In this paper, we investigate an efficient implicit scheme for the numerical simulation of chemical enhanced oil recovery technique for oil fields. For the sake of brevity, we only focus on flows with polymer to describe the physical and numerical models. In this framework, we consider a black oil model upgraded with the polymer modeling. We assume the polymer only transported in the water phase or adsorbed on the rock following a Langmuir isotherm. The polymer reduces the water phase mobility which can change drastically the behavior of water oil interfaces. Then, we propose a fractional step technique to resolve implicitly the system. The first step is devoted to the resolution of the black oil subsystem and the second to the polymer mass conservation. In such a way, jacobian matrices coming from the implicit formulation have a moderate size and preserve solvers efficiency. Nevertheless, the coupling between the black-oil subsystem and the polymer is not fully resolved. For efficiency and accuracy comparison, we propose an explicit scheme for the polymer for which large time step is prohibited due to its CFL (Courant-Friedrichs-Levy criterion and consequently approximates accurately the coupling. Numerical experiments with polymer are simulated : a core flood, a 5-spot reservoir with surfactant and ions and a 3D real case. Comparisons are performed between the polymer explicit and implicit scheme. They prove that our polymer implicit scheme is efficient, robust and resolves accurately the coupling physics. The development and the simulations have been performed with the software PumaFlow [PumaFlow (2013 Reference manual, release V600, Beicip Franlab].

  2. Compensation of oscillation coupling induced by solenoids

    International Nuclear Information System (INIS)

    Zelinskij, A.Yu.; Karnaukhov, I.M.; Shcherbakov, A.A.

    1988-01-01

    Methods for construction of various schemes of oscillation coupling compensation, induced by solenoids in charged particle storage rings, are described. Peculiarities of magnetic structure, enabling to localize oscillation coupling in wide energy range are discussed. Results of calculation of compensation schemes for design of NR-2000 storage ring spin rotation are presented

  3. The Bacillus subtilis Conjugative Plasmid pLS20 Encodes Two Ribbon-Helix-Helix Type Auxiliary Relaxosome Proteins That Are Essential for Conjugation.

    Science.gov (United States)

    Miguel-Arribas, Andrés; Hao, Jian-An; Luque-Ortega, Juan R; Ramachandran, Gayetri; Val-Calvo, Jorge; Gago-Córdoba, César; González-Álvarez, Daniel; Abia, David; Alfonso, Carlos; Wu, Ling J; Meijer, Wilfried J J

    2017-01-01

    Bacterial conjugation is the process by which a conjugative element (CE) is transferred horizontally from a donor to a recipient cell via a connecting pore. One of the first steps in the conjugation process is the formation of a nucleoprotein complex at the origin of transfer ( oriT ), where one of the components of the nucleoprotein complex, the relaxase, introduces a site- and strand specific nick to initiate the transfer of a single DNA strand into the recipient cell. In most cases, the nucleoprotein complex involves, besides the relaxase, one or more additional proteins, named auxiliary proteins, which are encoded by the CE and/or the host. The conjugative plasmid pLS20 replicates in the Gram-positive Firmicute bacterium Bacillus subtilis . We have recently identified the relaxase gene and the oriT of pLS20, which are separated by a region of almost 1 kb. Here we show that this region contains two auxiliary genes that we name aux1 LS20 and aux2 LS20 , and which we show are essential for conjugation. Both Aux1 LS20 and Aux2 LS20 are predicted to contain a Ribbon-Helix-Helix DNA binding motif near their N-terminus. Analyses of the purified proteins show that Aux1 LS20 and Aux2 LS20 form tetramers and hexamers in solution, respectively, and that they both bind preferentially to oriT LS20 , although with different characteristics and specificities. In silico analyses revealed that genes encoding homologs of Aux1 LS20 and/or Aux2 LS20 are located upstream of almost 400 relaxase genes of the Rel LS20 family (MOB L ) of relaxases. Thus, Aux1 LS20 and Aux2 LS20 of pLS20 constitute the founding member of the first two families of auxiliary proteins described for CEs of Gram-positive origin.

  4. An image encryption scheme based on the MLNCML system using DNA sequences

    Science.gov (United States)

    Zhang, Ying-Qian; Wang, Xing-Yuan; Liu, Jia; Chi, Ze-Lin

    2016-07-01

    We propose a new image scheme based on the spatiotemporal chaos of the Mixed Linear-Nonlinear Coupled Map Lattices (MLNCML). This spatiotemporal chaotic system has more cryptographic features in dynamics than the system of Coupled Map Lattices (CML). In the proposed scheme, we employ the strategy of DNA computing and one time pad encryption policy, which can enhance the sensitivity to the plaintext and resist differential attack, brute-force attack, statistical attack and plaintext attack. Simulation results and theoretical analysis indicate that the proposed scheme has superior high security.

  5. A translationally invariant RPA-calculation for 16O on the basis of an algebraic solution of the many-body oscillator problem

    International Nuclear Information System (INIS)

    Schwesinger, B.

    1978-01-01

    The solution of the many-body oscillator problem is used as a basis for a RPA-calculation of 16 O. The calculation is performed in a LS-coupling scheme with an interaction containing central, spin-orbit and tensor forces. The main differences with conventional RPA-calculations occur for the transition probabilities. (orig.) [de

  6. Implementation of suitable flow injection/sequential-sample separation/preconcentration schemes for determination of trace metal concentrations using detection by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Hansen, Elo Harald; Wang, Jianhua

    2002-01-01

    Various preconditioning procedures encomprising appropriate separation/preconcentration schemes in order to obtain optimal sensitivity and selectivity characteristics when using electrothermal atomic absorption spectrometry (ETAAS) and inductively coupled plasma mass spectrometry (ICPMS...

  7. The Bacillus subtilis Conjugative Plasmid pLS20 Encodes Two Ribbon-Helix-Helix Type Auxiliary Relaxosome Proteins That Are Essential for Conjugation

    Directory of Open Access Journals (Sweden)

    Andrés Miguel-Arribas

    2017-11-01

    Full Text Available Bacterial conjugation is the process by which a conjugative element (CE is transferred horizontally from a donor to a recipient cell via a connecting pore. One of the first steps in the conjugation process is the formation of a nucleoprotein complex at the origin of transfer (oriT, where one of the components of the nucleoprotein complex, the relaxase, introduces a site- and strand specific nick to initiate the transfer of a single DNA strand into the recipient cell. In most cases, the nucleoprotein complex involves, besides the relaxase, one or more additional proteins, named auxiliary proteins, which are encoded by the CE and/or the host. The conjugative plasmid pLS20 replicates in the Gram-positive Firmicute bacterium Bacillus subtilis. We have recently identified the relaxase gene and the oriT of pLS20, which are separated by a region of almost 1 kb. Here we show that this region contains two auxiliary genes that we name aux1LS20 and aux2LS20, and which we show are essential for conjugation. Both Aux1LS20 and Aux2LS20 are predicted to contain a Ribbon-Helix-Helix DNA binding motif near their N-terminus. Analyses of the purified proteins show that Aux1LS20 and Aux2LS20 form tetramers and hexamers in solution, respectively, and that they both bind preferentially to oriTLS20, although with different characteristics and specificities. In silico analyses revealed that genes encoding homologs of Aux1LS20 and/or Aux2LS20 are located upstream of almost 400 relaxase genes of the RelLS20 family (MOBL of relaxases. Thus, Aux1LS20 and Aux2LS20 of pLS20 constitute the founding member of the first two families of auxiliary proteins described for CEs of Gram-positive origin.

  8. Detectors plans for LS1

    International Nuclear Information System (INIS)

    Nessi, M.

    2012-01-01

    All experiments plan an effective usage of the LS1 shutdown period. After three years of running they will go through a consolidation phase, mostly to fix problems that have emerged over time, like single points of failure in the infrastructure, failures of low-voltage power supplies and optical links. Upgrades of some detector components will start, mainly related to the beam pipe, the innermost tracker elements and the trigger system. Detector components, which had to be staged for cost reasons in 2003, will then enter into the detector setup. The goal is to be fully ready for the new energy regime at nominal luminosity. This article reviews the planned maintenance and modification works for ATLAS, CMS, LHCb and ALICE experiments. (author)

  9. A Low-order Coupled Chemistry Meteorology Model for Testing Online and Offline Advanced Data Assimilation Schemes

    Science.gov (United States)

    Bocquet, M.; Haussaire, J. M.

    2015-12-01

    Bocquet and Sakov have recently introduced a low-order model based on the coupling of thechaotic Lorenz-95 model which simulates winds along a mid-latitude circle, with thetransport of a tracer species advected by this wind field. It has been used to testadvanced data assimilation methods with an online model that couples meteorology andtracer transport. In the present study, the tracer subsystem of the model is replacedwith a reduced photochemistry module meant to emulate reactive air pollution. Thiscoupled chemistry meteorology model, the L95-GRS model, mimics continental andtranscontinental transport and photochemistry of ozone, volatile organic compounds andnitrogen dioxides.The L95-GRS is specially useful in testing advanced data assimilation schemes, such as theiterative ensemble Kalman smoother (IEnKS) that combines the best of ensemble andvariational methods. The model provides useful insights prior to any implementation ofthe data assimilation method on larger models. For instance, online and offline dataassimilation strategies based on the ensemble Kalman filter or the IEnKS can easily beevaluated with it. It allows to document the impact of species concentration observationson the wind estimation. The model also illustrates a long standing issue in atmosphericchemistry forecasting: the impact of the wind chaotic dynamics and of the chemical speciesnon-chaotic but highly nonlinear dynamics on the selected data assimilation approach.

  10. Error-prone PCR mutation of Ls-EPSPS gene from Liriope spicata conferring to its enhanced glyphosate-resistance.

    Science.gov (United States)

    Mao, Chanjuan; Xie, Hongjie; Chen, Shiguo; Valverde, Bernal E; Qiang, Sheng

    2017-09-01

    Liriope spicata (Thunb.) Lour has a unique LsEPSPS structure contributing to the highest-ever-recognized natural glyphosate tolerance. The transformed LsEPSPS confers increased glyphosate resistance to E. coli and A. thaliana. However, the increased glyphosate-resistance level is not high enough to be of commercial value. Therefore, LsEPSPS was subjected to error-prone PCR to screen mutant EPSPS genes capable of endowing higher resistance levels. A mutant designated as ELs-EPSPS having five mutated amino acids (37Val, 67Asn, 277Ser, 351Gly and 422Gly) was selected for its ability to confer improved resistance to glyphosate. Expression of ELs-EPSPS in recombinant E. coli BL21 (DE3) strains enhanced resistance to glyphosate in comparison to both the LsEPSPS-transformed and -untransformed controls. Furthermore, transgenic ELs-EPSPS A. thaliana was about 5.4 fold and 2-fold resistance to glyphosate compared with the wild-type and the Ls-EPSPS-transgenic plants, respectively. Therefore, the mutated ELs-EPSPS gene has potential value for has potential for the development of glyphosate-resistant crops. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Realistic Rashba and Dresselhaus spin-orbit coupling for neutral atoms

    International Nuclear Information System (INIS)

    Campbell, D. L.; Spielman, I. B.; Juzeliunas, G.

    2011-01-01

    We describe a new class of atom-laser coupling schemes which lead to spin-orbit-coupled Hamiltonians for ultracold neutral atoms. By properly setting the optical phases, a pair of degenerate pseudospin (a linear combination of internal atomic) states emerge as the lowest-energy eigenstates in the spectrum and are thus immune to collisionally induced decay. These schemes use N cyclically coupled ground or metastable internal states. We focus on two situations: a three-level case and a four-level case, where the latter adds a controllable Dresselhaus contribution. We describe an implementation of the four-level scheme for 87 Rb and analyze its sensitivity to typical laboratory noise sources. Last, we argue that the Rashba Hamiltonian applies only in the large intensity limit since any laser coupling scheme will produce terms nonlinear in momentum that decline with intensity.

  12. Introducing instrumental variables in the LS-SVM based identification framework

    NARCIS (Netherlands)

    Laurain, V.; Zheng, W-X.; Toth, R.

    2011-01-01

    Least-Squares Support Vector Machines (LS-SVM) represent a promising approach to identify nonlinear systems via nonparametric estimation of the nonlinearities in a computationally and stochastically attractive way. All the methods dedicated to the solution of this problem rely on the minimization of

  13. Application and evaluation of LS-PIV technique for the monitoring of river surface velocities in high flow conditions

    OpenAIRE

    Jodeau , M.; Hauet , A.; Paquier , A.; Le Coz , J.; Dramais , G.

    2008-01-01

    Large Scale Particle Image Velocimetry (LS-PIV) is used to measure the surface flow velocities in a mountain stream during high flow conditions due to a reservoir release. A complete installation including video acquisition from a mobile elevated viewpoint and artificial flow seeding has been developed and implemented. The LS-PIV method was adapted in order to take into account the specific constraints of these high flow conditions. Using a usual LS-PIV data processing, significant variations...

  14. Shock Transmission Analyses of a Simplified Frigate Compartment Using LS-DYNA

    National Research Council Canada - National Science Library

    Trouwborst, W

    1999-01-01

    This report gives results as obtained with finite element analyses using the explicit finite element program LS-DYNA for a longitudinal slice of a frigate's compartment loaded with a shock pulse based...

  15. EN-CV during LS1: upgrade, consolidation, maintenance, operation

    International Nuclear Information System (INIS)

    Nonis, M.

    2012-01-01

    The Cooling and Ventilation (CV) Group in the Engineering Department (EN) will be heavily involved in several projects and activities during the long shutdown in 2013 and 2014 (LS1) within a time-frame limited to around twelve months. According to the requests received so far, most projects are related to the upgrade of users' equipment, consolidation work, and the construction of new plants. However, through the experience gained from the first years of the LHC run, some projects are also needed to adapt the existing installations to the new operating parameters. Some of these projects are presented hereafter, outlining the impact that they will have on operational working conditions or risks of breakdown. Among these projects we find: the PM32 raising pumps, the cooling of the CERN Control Center, R2E, the backup cooling towers for ATLAS and cryogenics, a thermosyphon for ATLAS, or new pumps in UWs. Finally, EN-CV activities during LS1 for maintenance, operation, and commissioning will be mentioned since they represent a major workload for the Group

  16. [Rapid determination of COD in aquaculture water based on LS-SVM with ultraviolet/visible spectroscopy].

    Science.gov (United States)

    Liu, Xue-Mei; Zhang, Hai-Liang

    2014-10-01

    Ultraviolet/visible (UV/Vis) spectroscopy was studied for the rapid determination of chemical oxygen demand (COD), which was an indicator to measure the concentration of organic matter in aquaculture water. In order to reduce the influence of the absolute noises of the spectra, the extracted 135 absorbance spectra were preprocessed by Savitzky-Golay smoothing (SG), EMD, and wavelet transform (WT) methods. The preprocessed spectra were then used to select latent variables (LVs) by partial least squares (PLS) methods. Partial least squares (PLS) was used to build models with the full spectra, and back- propagation neural network (BPNN) and least square support vector machine (LS-SVM) were applied to build models with the selected LVs. The overall results showed that BPNN and LS-SVM models performed better than PLS models, and the LS-SVM models with LVs based on WT preprocessed spectra obtained the best results with the determination coefficient (r2) and RMSE being 0. 83 and 14. 78 mg · L(-1) for calibration set, and 0.82 and 14.82 mg · L(-1) for the prediction set respectively. The method showed the best performance in LS-SVM model. The results indicated that it was feasible to use UV/Vis with LVs which were obtained by PLS method, combined with LS-SVM calibration could be applied to the rapid and accurate determination of COD in aquaculture water. Moreover, this study laid the foundation for further implementation of online analysis of aquaculture water and rapid determination of other water quality parameters.

  17. The impact on UT/LS cirrus clouds in the CAM/CARMA model using a new interactive aerosol parameterization.

    Science.gov (United States)

    Maloney, C.; Toon, B.; Bardeen, C.

    2017-12-01

    Recent studies indicate that heterogeneous nucleation may play a large role in cirrus cloud formation in the UT/LS, a region previously thought to be primarily dominated by homogeneous nucleation. As a result, it is beneficial to ensure that general circulation models properly represent heterogeneous nucleation in ice cloud simulations. Our work strives towards addressing this issue in the NSF/DOE Community Earth System Model's atmospheric model, CAM. More specifically we are addressing the role of heterogeneous nucleation in the coupled sectional microphysics cloud model, CARMA. Currently, our CAM/CARMA cirrus model only performs homogenous ice nucleation while ignoring heterogeneous nucleation. In our work, we couple the CAM/CARMA cirrus model with the Modal Aerosol Model (MAM). By combining the aerosol model with CAM/CARMA we can both account for heterogeneous nucleation, as well as directly link the sulfates used for homogeneous nucleation to computed fields instead of the current static field being utilized. Here we present our initial results and compare our findings to observations from the long running CALIPSO and MODIS satellite missions.

  18. Adaptive elimination of synchronization in coupled oscillator

    Science.gov (United States)

    Zhou, Shijie; Ji, Peng; Zhou, Qing; Feng, Jianfeng; Kurths, Jürgen; Lin, Wei

    2017-08-01

    We present here an adaptive control scheme with a feedback delay to achieve elimination of synchronization in a large population of coupled and synchronized oscillators. We validate the feasibility of this scheme not only in the coupled Kuramoto’s oscillators with a unimodal or bimodal distribution of natural frequency, but also in two representative models of neuronal networks, namely, the FitzHugh-Nagumo spiking oscillators and the Hindmarsh-Rose bursting oscillators. More significantly, we analytically illustrate the feasibility of the proposed scheme with a feedback delay and reveal how the exact topological form of the bimodal natural frequency distribution influences the scheme performance. We anticipate that our developed scheme will deepen the understanding and refinement of those controllers, e.g. techniques of deep brain stimulation, which have been implemented in remedying some synchronization-induced mental disorders including Parkinson disease and epilepsy.

  19. Adaptive elimination of synchronization in coupled oscillator

    International Nuclear Information System (INIS)

    Zhou, Shijie; Lin, Wei; Ji, Peng; Feng, Jianfeng; Zhou, Qing; Kurths, Jürgen

    2017-01-01

    We present here an adaptive control scheme with a feedback delay to achieve elimination of synchronization in a large population of coupled and synchronized oscillators. We validate the feasibility of this scheme not only in the coupled Kuramoto’s oscillators with a unimodal or bimodal distribution of natural frequency, but also in two representative models of neuronal networks, namely, the FitzHugh–Nagumo spiking oscillators and the Hindmarsh–Rose bursting oscillators. More significantly, we analytically illustrate the feasibility of the proposed scheme with a feedback delay and reveal how the exact topological form of the bimodal natural frequency distribution influences the scheme performance. We anticipate that our developed scheme will deepen the understanding and refinement of those controllers, e.g. techniques of deep brain stimulation, which have been implemented in remedying some synchronization-induced mental disorders including Parkinson disease and epilepsy. (paper)

  20. Comparison of electromagnetically induced transparency schemes in semiconductor quantum dot structures: Impact of many-body interactions

    DEFF Research Database (Denmark)

    Houmark-Nielsen, Jakob; Nielsen, Torben Roland; Mørk, Jesper

    2009-01-01

    an important impact on the slow light properties. In the case of the Lambda and V schemes, the minimum required coupling power to achieve slow light is significantly reduced by many-body interactions. V type schemes are found to be generally preferable due to a favorable redistribution of carriers in energy......We investigate the impact of many-body interactions on group-velocity slowdown achieved via electromagnetically induced transparency in quantum dots using three different coupling-probe schemes (ladder, V, and Lambda, respectively). We find that for all schemes many-body interactions have...

  1. Nanoscale characterization and local piezoelectric properties of lead-free KNN-LT-LS thin films

    Energy Technology Data Exchange (ETDEWEB)

    Abazari, M; Safari, A [Glenn Howatt Electroceramics Laboratories, Department of Materials Science and Engineering, Rutgers-The state University of New Jersey, Piscataway, NJ 08854 (United States); Choi, T; Cheong, S-W [Rutgers Center for Emergent Materials, Department of Physics and Astronomy, Rutgers-The state University of New Jersey, Piscataway, NJ 08854 (United States)

    2010-01-20

    We report the observation of domain structure and piezoelectric properties of pure and Mn-doped (K{sub 0.44},Na{sub 0.52},Li{sub 0.04})(Nb{sub 0.84},Ta{sub 0.1},Sb{sub 0.06})O{sub 3} (KNN-LT-LS) thin films on SrTiO{sub 3} substrates. It is revealed that, using piezoresponse force microscopy, ferroelectric domain structure in such 500 nm thin films comprised of primarily 180{sup 0} domains. This was in accordance with the tetragonal structure of the films, confirmed by relative permittivity measurements and x-ray diffraction patterns. Effective piezoelectric coefficient (d{sub 33}) of the films were calculated using piezoelectric displacement curves and shown to be {approx}53 pm V{sup -1} for pure KNN-LT-LS thin films. This value is among the highest values reported for an epitaxial lead-free thin film and shows a great potential for KNN-LT-LS to serve as an alternative to PZT thin films in future applications.

  2. Nanoscale characterization and local piezoelectric properties of lead-free KNN-LT-LS thin films

    Science.gov (United States)

    Abazari, M.; Choi, T.; Cheong, S.-W.; Safari, A.

    2010-01-01

    We report the observation of domain structure and piezoelectric properties of pure and Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.1,Sb0.06)O3 (KNN-LT-LS) thin films on SrTiO3 substrates. It is revealed that, using piezoresponse force microscopy, ferroelectric domain structure in such 500 nm thin films comprised of primarily 180° domains. This was in accordance with the tetragonal structure of the films, confirmed by relative permittivity measurements and x-ray diffraction patterns. Effective piezoelectric coefficient (d33) of the films were calculated using piezoelectric displacement curves and shown to be ~53 pm V-1 for pure KNN-LT-LS thin films. This value is among the highest values reported for an epitaxial lead-free thin film and shows a great potential for KNN-LT-LS to serve as an alternative to PZT thin films in future applications.

  3. Novel communication scheme based on chaotic Roessler circuits

    International Nuclear Information System (INIS)

    GarcIa-Lopez, J H; Jaimes-Reategui, R; Pisarchik, A N; MurguIa-Hernandez, A; Medina-Gutierrez, C; Valdivia-Hernadez, R; Villafana-Rauda, E

    2005-01-01

    We present a novel synchronization scheme for secure communication with two chaotic unidirectionally coupled Roessler circuits. The circuits are synchronized via one of the variables, while a signal is transmitted through another variable. We show that this scheme allows more stable communications. The system dynamics is studied numerically and experimentally in a wide range of a control parameter. The possibility of secure communications with an audio signal is demonstrated

  4. Inverse European Latitudinal Cline at the timeless Locus of Drosophila melanogaster Reveals Selection on a Clock Gene: Population Genetics of ls-tim.

    Science.gov (United States)

    Zonato, Valeria; Vanin, Stefano; Costa, Rodolfo; Tauber, Eran; Kyriacou, Charalambos P

    2018-02-01

    The spread of adaptive genetic variants in populations is a cornerstone of evolutionary theory but with relatively few biologically well-understood examples. Previous work on the ls-tim variant of timeless, which encodes the light-sensitive circadian regulator in Drosophila melanogaster, suggests that it may have originated in southeastern Italy. Flies characterized by the new allele show photoperiod-related phenotypes likely to be adaptive in seasonal environments. ls-tim may be spreading from its point of origin in Italy by directional selection, but there are alternative explanations for its observed clinal geographical distribution, including balancing selection and demography. From population analyses of ls-tim frequencies collected on the eastern side of the Iberian Peninsula, we show that ls-tim frequencies are inverted compared with those in Italy. This pattern is consistent with a scenario of directional selection rather than latitude-associated balancing selection. Neutrality tests further reveal the signature of directional selection at the ls-tim site, which is reduced a few kb pairs either side of ls-tim. A reanalysis of allele frequencies from a large number of microsatellite loci do not demonstrate any frequent ls-tim-like spatial patterns, so a general demographic effect or population expansion from southeastern Italy cannot readily explain current ls-tim frequencies. Finally, a revised estimate of the age of ls-tim allele using linkage disequilibrium and coalescent-based approaches reveals that it may be only 300 to 3000 years old, perhaps explaining why it has not yet gone to fixation. ls-tim thus provides a rare temporal snapshot of a new allele that has come under selection before it reaches equilibrium.

  5. Scheme-Independent Predictions in QCD: Commensurate Scale Relations and Physical Renormalization Schemes

    International Nuclear Information System (INIS)

    Brodsky, Stanley J.

    1998-01-01

    Commensurate scale relations are perturbative QCD predictions which relate observable to observable at fixed relative scale, such as the ''generalized Crewther relation'', which connects the Bjorken and Gross-Llewellyn Smith deep inelastic scattering sum rules to measurements of the e + e - annihilation cross section. All non-conformal effects are absorbed by fixing the ratio of the respective momentum transfer and energy scales. In the case of fixed-point theories, commensurate scale relations relate both the ratio of couplings and the ratio of scales as the fixed point is approached. The relations between the observables are independent of the choice of intermediate renormalization scheme or other theoretical conventions. Commensurate scale relations also provide an extension of the standard minimal subtraction scheme, which is analytic in the quark masses, has non-ambiguous scale-setting properties, and inherits the physical properties of the effective charge α V (Q 2 ) defined from the heavy quark potential. The application of the analytic scheme to the calculation of quark-mass-dependent QCD corrections to the Z width is also reviewed

  6. Error function attack of chaos synchronization based encryption schemes.

    Science.gov (United States)

    Wang, Xingang; Zhan, Meng; Lai, C-H; Gang, Hu

    2004-03-01

    Different chaos synchronization based encryption schemes are reviewed and compared from the practical point of view. As an efficient cryptanalysis tool for chaos encryption, a proposal based on the error function attack is presented systematically and used to evaluate system security. We define a quantitative measure (quality factor) of the effective applicability of a chaos encryption scheme, which takes into account the security, the encryption speed, and the robustness against channel noise. A comparison is made of several encryption schemes and it is found that a scheme based on one-way coupled chaotic map lattices performs outstandingly well, as judged from quality factor. Copyright 2004 American Institute of Physics.

  7. Coupled atmosphere and land-surface assimilation of surface observations with a single column model and ensemble data assimilation

    Science.gov (United States)

    Rostkier-Edelstein, Dorita; Hacker, Joshua P.; Snyder, Chris

    2014-05-01

    Numerical weather prediction and data assimilation models are composed of coupled atmosphere and land-surface (LS) components. If possible, the assimilation procedure should be coupled so that observed information in one module is used to correct fields in the coupled module. There have been some attempts in this direction using optimal interpolation, nudging and 2/3DVAR data assimilation techniques. Aside from satellite remote sensed observations, reference height in-situ observations of temperature and moisture have been used in these studies. Among other problems, difficulties in coupled atmosphere and LS assimilation arise as a result of the different time scales characteristic of each component and the unsteady correlation between these components under varying flow conditions. Ensemble data-assimilation techniques rely on flow dependent observations-model covariances. Provided that correlations and covariances between land and atmosphere can be adequately simulated and sampled, ensemble data assimilation should enable appropriate assimilation of observations simultaneously into the atmospheric and LS states. Our aim is to explore assimilation of reference height in-situ temperature and moisture observations into the coupled atmosphere-LS modules(simultaneously) in NCAR's WRF-ARW model using the NCAR's DART ensemble data-assimilation system. Observing system simulation experiments (OSSEs) are performed using the single column model (SCM) version of WRF. Numerical experiments during a warm season are centered on an atmospheric and soil column in the South Great Plains. Synthetic observations are derived from "truth" WRF-SCM runs for a given date,initialized and forced using North American Regional Reanalyses (NARR). WRF-SCM atmospheric and LS ensembles are created by mixing the atmospheric and soil NARR profile centered on a given date with that from another day (randomly chosen from the same season) with weights drawn from a logit-normal distribution. Three

  8. DISEÑO Y EVALUACIÓN DE UN CLASIFICADOR DE TEXTURAS BASADO EN LS-SVM

    Directory of Open Access Journals (Sweden)

    Beitmantt Cárdenas Quintero

    2013-07-01

    Full Text Available Evaluar el desempeño y el costo computacional de diferentes arquitecturas y metodologías Least Square Support Vector Machine (LS-SVM ante la segmentación de imágenes por textura y a partir de dichos resultados postular un modelo de un clasificador de texturas LS-SVM.  Metodología: Ante un problema de clasificación binaria representado por la segmentación  de 32 imágenes, organizadas en 4 grupos y formadas por pares de texturas típicas (granito/corteza, ladrillo/tapicería, madera/mármol, tejido/pelaje, se mide y compara el desempeño y el costo computacional de dos tipos de núcleo (Radial / Polinomial, dos funciones de optimización (mínimo local / búsqueda exhaustiva y dos funciones de costo (validación cruzada aleatoria / Validación cruzada dejando al menos uno en una LS-SVM que toma como entrada los pixeles que conforman la vecindad cruz del pixel a evaluar (no se hace extracción de características. Resultados: LS-SVM como clasificador de texturas, presenta mejor desempeño y exige menor costo computacional cuando utiliza un kernel de base radial y una función de optimización basada en un algoritmo de búsqueda de mínimos locales acompañado de una función de costo que use validación cruzada aleatoria.

  9. Scalability of Direct Solver for Non-stationary Cahn-Hilliard Simulations with Linearized time Integration Scheme

    KAUST Repository

    Woźniak, M.; Smołka, M.; Cortes, Adriano Mauricio; Paszyński, M.; Schaefer, R.

    2016-01-01

    We study the features of a new mixed integration scheme dedicated to solving the non-stationary variational problems. The scheme is composed of the FEM approximation with respect to the space variable coupled with a 3-leveled time integration scheme

  10. Immunomodulatory Effects of Lactobacillus salivarius LS01 and Bifidobacterium breve BR03, Alone and in Combination, on Peripheral Blood Mononuclear Cells of Allergic Asthmatics.

    Science.gov (United States)

    Drago, Lorenzo; De Vecchi, Elena; Gabrieli, Arianna; De Grandi, Roberta; Toscano, Marco

    2015-07-01

    The aim of this study was to evaluate probiotic characteristics of Lactobacillus salivarius LS01 and Bifidobacterium breve BR03 alone and in combination and their immunomodulatory activity in asthmatic subjects. Subjects affected by allergic asthma were recruited. Initially, LS01 and BR03 were analyzed for their growth compatibility by a broth compatibility assay. To study the antimicrobial activity of probiotic strains, an agar diffusion assay was performed. Finally, cytokine production by peripheral blood mononuclear cells (PBMCs) stimulated with LS01 and BR03 was determined by means of specific quantitative enzyme-linked immunosorbent assay (ELISA). The growth of some clinical pathogens were slightly inhibited by LS01 and LS01-BR03 co-culture supernatant not neutralized to pH 6.5, while only the growth of E. coli and S. aureus was inhibited by the supernatant of LS01 and LS01-BR03 neutralized to pH 6.5. Furthermore, LS01 and BR03 combination was able to decrease the secretion of proinflammatory cytokines by PBMCs, leading to an intense increase in IL-10 production. L. salivarius LS01 and B. breve BR03 showed promising probiotic properties and beneficial immunomodulatory activity that are increased when the 2 strains are used in combination in the same formulation.

  11. Ultrafast quantum computation in ultrastrongly coupled circuit QED systems

    Science.gov (United States)

    Wang, Yimin; Guo, Chu; Zhang, Guo-Qiang; Wang, Gangcheng; Wu, Chunfeng

    2017-01-01

    The latest technological progress of achieving the ultrastrong-coupling regime in circuit quantum electrodynamics (QED) systems has greatly promoted the developments of quantum physics, where novel quantum optics phenomena and potential computational benefits have been predicted. Here, we propose a scheme to accelerate the nontrivial two-qubit phase gate in a circuit QED system, where superconducting flux qubits are ultrastrongly coupled to a transmission line resonator (TLR), and two more TLRs are coupled to the ultrastrongly-coupled system for assistant. The nontrivial unconventional geometric phase gate between the two flux qubits is achieved based on close-loop displacements of the three-mode intracavity fields. Moreover, as there are three resonators contributing to the phase accumulation, the requirement of the coupling strength to realize the two-qubit gate can be reduced. Further reduction in the coupling strength to achieve a specific controlled-phase gate can be realized by adding more auxiliary resonators to the ultrastrongly-coupled system through superconducting quantum interference devices. We also present a study of our scheme with realistic parameters considering imperfect controls and noisy environment. Our scheme possesses the merits of ultrafastness and noise-tolerance due to the advantages of geometric phases. PMID:28281654

  12. Strong coupling and quasispinor representations of the SU(3) rotor model

    International Nuclear Information System (INIS)

    Rowe, D.J.; De Guise, H.

    1992-01-01

    We define a coupling scheme, in close parallel to the coupling scheme of Elliott and Wilsdon, in which nucleonic intrinsic spins are strongly coupled to SU(3) spatial wave functions. The scheme is proposed for shell-model calculations in strongly deformed nuclei and for semimicroscopic analyses of rotations in odd-mass nuclei and other nuclei for which the spin-orbit interaction is believed to play an important role. The coupling scheme extends the domain of utility of the SU(3) model, and the symplectic model, to heavy nuclei and odd-mass nuclei. It is based on the observation that the low angular-momentum states of an SU(3) irrep have properties that mimic those of a corresponding irrep of the rotor algebra. Thus, we show that strongly coupled spin-SU(3) bands behave like strongly coupled rotor bands with properties that approach those of irreducible representations of the rigid-rotor algebra in the limit of large SU(3) quantum numbers. Moreover, we determine that the low angular-momentum states of a strongly coupled band of states of half-odd integer angular momentum behave to a high degree of accuracy as if they belonged to an SU(3) irrep. These are the quasispinor SU(3) irreps referred to in the title. (orig.)

  13. High-energy emissions from the gamma-ray binary LS 5039

    Energy Technology Data Exchange (ETDEWEB)

    Takata, J.; Leung, Gene C. K.; Cheng, K. S. [Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong); Tam, P. H. T.; Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China); Hui, C. Y., E-mail: takata@hku.hk, E-mail: gene930@connect.hku.hk, E-mail: hrspksc@hku.hk [Department of Astronomy and Space Science, Chungnam National University, Daejeon (Korea, Republic of)

    2014-07-20

    We study mechanisms of multi-wavelength emissions (X-ray, GeV, and TeV gamma-rays) from the gamma-ray binary LS 5039. This paper is composed of two parts. In the first part, we report on results of observational analysis using 4 yr data of the Fermi Large Area Telescope. Due to the improvement of instrumental response function and increase of the statistics, the observational uncertainties of the spectrum in the ∼100-300 MeV bands and >10 GeV bands are significantly improved. The present data analysis suggests that the 0.1-100 GeV emissions from LS 5039 contain three different components: (1) the first component contributes to <1 GeV emissions around superior conjunction, (2) the second component dominates in the 1-10 GeV energy bands, and (3) the third component is compatible with the lower-energy tail of the TeV emissions. In the second part, we develop an emission model to explain the properties of the phase-resolved emissions in multi-wavelength observations. Assuming that LS 5039 includes a pulsar, we argue that emissions from both the magnetospheric outer gap and the inverse-Compton scattering process of cold-relativistic pulsar wind contribute to the observed GeV emissions. We assume that the pulsar is wrapped by two kinds of termination shock: Shock-I due to the interaction between the pulsar wind and the stellar wind and Shock-II due to the effect of the orbital motion. We propose that the X-rays are produced by the synchrotron radiation at the Shock-I region and the TeV gamma-rays are produced by the inverse-Compton scattering process at the Shock-II region.

  14. Remediation of Learning Disable Children Following L.S. Vygotsky's Approach

    Directory of Open Access Journals (Sweden)

    Janna M. Glozman

    2011-01-01

    Full Text Available The paper defines remediating education, its peculiarities against trasitional education, main tasks and principles, based upon the cultural-historical theory of L.S. Vygotsky. Base functional systems formed during remediation are discussed. Peculiarities of individual, group and dyadic methods of remediation are described with regard to its potential for mediating child's activity.

  15. A new Em-like protein from Lactuca sativa, LsEm1, enhances drought and salt stress tolerance in Escherichia coli and rice.

    Science.gov (United States)

    Xiang, Dian-Jun; Man, Li-Li; Zhang, Chun-Lan; Peng-Liu; Li, Zhi-Gang; Zheng, Gen-Chang

    2018-02-07

    Late embryogenesis abundant (LEA) proteins are closely related to abiotic stress tolerance of plants. In the present study, we identified a novel Em-like gene from lettuce, termed LsEm1, which could be classified into group 1 LEA proteins, and shared high homology with Cynara cardunculus Em protein. The LsEm1 protein contained three different 20-mer conserved elements (C-element, N-element, and M-element) in the C-termini, N-termini, and middle-region, respectively. The LsEm1 mRNAs were accumulated in all examined tissues during the flowering and mature stages, with a little accumulation in the roots and leaves during the seedling stage. Furthermore, the LsEm1 gene was also expressed in response to salt, dehydration, abscisic acid (ABA), and cold stresses in young seedlings. The LsEm1 protein could effectively reduce damage to the lactate dehydrogenase (LDH) and protect LDH activity under desiccation and salt treatments. The Escherichia coli cells overexpressing the LsEm1 gene showed a growth advantage over the control under drought and salt stresses. Moreover, LsEm1-overexpressing rice seeds were relatively sensitive to exogenously applied ABA, suggesting that the LsEm1 gene might depend on an ABA signaling pathway in response to environmental stresses. The transgenic rice plants overexpressing the LsEm1 gene showed higher tolerance to drought and salt stresses than did wild-type (WT) plants on the basis of the germination performances, higher survival rates, higher chlorophyll content, more accumulation of soluble sugar, lower relative electrolyte leakage, and higher superoxide dismutase activity under stress conditions. The LsEm1-overexpressing rice lines also showed less yield loss compared with WT rice under stress conditions. Furthermore, the LsEm1 gene had a positive effect on the expression of the OsCDPK9, OsCDPK13, OsCDPK15, OsCDPK25, and rab21 (rab16a) genes in transgenic rice under drought and salt stress conditions, implying that overexpression of these

  16. Novel Hybrid of LS-SVM and Kalman Filter for GPS/INS Integration

    Science.gov (United States)

    Xu, Zhenkai; Li, Yong; Rizos, Chris; Xu, Xiaosu

    Integration of Global Positioning System (GPS) and Inertial Navigation System (INS) technologies can overcome the drawbacks of the individual systems. One of the advantages is that the integrated solution can provide continuous navigation capability even during GPS outages. However, bridging the GPS outages is still a challenge when Micro-Electro-Mechanical System (MEMS) inertial sensors are used. Methods being currently explored by the research community include applying vehicle motion constraints, optimal smoother, and artificial intelligence (AI) techniques. In the research area of AI, the neural network (NN) approach has been extensively utilised up to the present. In an NN-based integrated system, a Kalman filter (KF) estimates position, velocity and attitude errors, as well as the inertial sensor errors, to output navigation solutions while GPS signals are available. At the same time, an NN is trained to map the vehicle dynamics with corresponding KF states, and to correct INS measurements when GPS measurements are unavailable. To achieve good performance it is critical to select suitable quality and an optimal number of samples for the NN. This is sometimes too rigorous a requirement which limits real world application of NN-based methods.The support vector machine (SVM) approach is based on the structural risk minimisation principle, instead of the minimised empirical error principle that is commonly implemented in an NN. The SVM can avoid local minimisation and over-fitting problems in an NN, and therefore potentially can achieve a higher level of global performance. This paper focuses on the least squares support vector machine (LS-SVM), which can solve highly nonlinear and noisy black-box modelling problems. This paper explores the application of the LS-SVM to aid the GPS/INS integrated system, especially during GPS outages. The paper describes the principles of the LS-SVM and of the KF hybrid method, and introduces the LS-SVM regression algorithm. Field

  17. LS1 Report: The cryogenic line goes through the scanner

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    In spite of the complexity of LS1, with many different activities taking place in parallel and sometimes overlapping, the dashboard shows that work is progressing on schedule. This week, teams have started X-raying the cryogenic line to examine its condition in minute detail.   The LS1 schedule is pretty unfathomable for those who don't work in the tunnels or installations, but if you look down all the columns and stop at the line indicating today’s date, you can see that all of the priority and critical items are bang on time, like a Swiss watch. More specifically: the SMACC project in the LHC is on schedule, with a new testing phase for the interconnections which have already been consolidated; preparations are under way for the cable replacement campaign at Point 1 of the SPS (about 20% of the cables will not be replaced as they are completely unused); and the demineralised water distribution line is back in service, as are the electrical substations for the 400 and 66 kV line...

  18. A Data Gathering Scheme in Wireless Sensor Networks Based on Synchronization of Chaotic Spiking Oscillator Networks

    International Nuclear Information System (INIS)

    Nakano, Hidehiro; Utani, Akihide; Miyauchi, Arata; Yamamoto, Hisao

    2011-01-01

    This paper studies chaos-based data gathering scheme in multiple sink wireless sensor networks. In the proposed scheme, each wireless sensor node has a simple chaotic oscillator. The oscillators generate spike signals with chaotic interspike intervals, and are impulsively coupled by the signals via wireless communication. Each wireless sensor node transmits and receives sensor information only in the timing of the couplings. The proposed scheme can exhibit various chaos synchronous phenomena and their breakdown phenomena, and can effectively gather sensor information with the significantly small number of transmissions and receptions compared with the conventional scheme. Also, the proposed scheme can flexibly adapt various wireless sensor networks not only with a single sink node but also with multiple sink nodes. This paper introduces our previous works. Through simulation experiments, we show effectiveness of the proposed scheme and discuss its development potential.

  19. DISEÑO Y EVALUACIÓN DE UN CLASIFICADOR DE TEXTURAS BASADO EN LS-SVM

    OpenAIRE

    Beitmantt Cárdenas Quintero; Nelson Enrique Vera Parra; Pablo Emilio Rozo García

    2013-01-01

    Evaluar el desempeño y el costo computacional de diferentes arquitecturas y metodologías Least Square Support Vector Machine (LS-SVM) ante la segmentación de imágenes por textura y a partir de dichos resultados postular un modelo de un clasificador de texturas LS-SVM.  Metodología: Ante un problema de clasificación binaria representado por la segmentación  de 32 imágenes, organizadas en 4 grupos y formadas por pares de texturas típicas (granito/corteza, ladrillo/tapicería, madera/mármol, teji...

  20. Mobility of the native Bacillus subtilis conjugative plasmid pLS20 is regulated by intercellular signaling.

    Science.gov (United States)

    Singh, Praveen K; Ramachandran, Gayetri; Ramos-Ruiz, Ricardo; Peiró-Pastor, Ramón; Abia, David; Wu, Ling J; Meijer, Wilfried J J

    2013-10-01

    Horizontal gene transfer mediated by plasmid conjugation plays a significant role in the evolution of bacterial species, as well as in the dissemination of antibiotic resistance and pathogenicity determinants. Characterization of their regulation is important for gaining insights into these features. Relatively little is known about how conjugation of Gram-positive plasmids is regulated. We have characterized conjugation of the native Bacillus subtilis plasmid pLS20. Contrary to the enterococcal plasmids, conjugation of pLS20 is not activated by recipient-produced pheromones but by pLS20-encoded proteins that regulate expression of the conjugation genes. We show that conjugation is kept in the default "OFF" state and identified the master repressor responsible for this. Activation of the conjugation genes requires relief of repression, which is mediated by an anti-repressor that belongs to the Rap family of proteins. Using both RNA sequencing methodology and genetic approaches, we have determined the regulatory effects of the repressor and anti-repressor on expression of the pLS20 genes. We also show that the activity of the anti-repressor is in turn regulated by an intercellular signaling peptide. Ultimately, this peptide dictates the timing of conjugation. The implications of this regulatory mechanism and comparison with other mobile systems are discussed.

  1. LHC Experimental Beam Pipe Upgrade during LS1

    CERN Document Server

    Lanza, G; Baglin, V; Chiggiato, P

    2014-01-01

    The LHC experimental beam pipes are being improved during the ongoing Long Shutdown 1 (LS1). Several vacuum chambers have been tested and validated before their installation inside the detectors. The validation tests include: leak tightness, ultimate vacuum pressure, material outgassing rate, and residual gas composition. NEG coatings are assessed by sticking probability measurement with the help of Monte Carlo simulations. In this paper the motivation for the beam pipe upgrade, the validation tests of the components and the results are presented and discussed.

  2. QuBiLS-MAS, open source multi-platform software for atom- and bond-based topological (2D) and chiral (2.5D) algebraic molecular descriptors computations.

    Science.gov (United States)

    Valdés-Martiní, José R; Marrero-Ponce, Yovani; García-Jacas, César R; Martinez-Mayorga, Karina; Barigye, Stephen J; Vaz d'Almeida, Yasser Silveira; Pham-The, Hai; Pérez-Giménez, Facundo; Morell, Carlos A

    2017-06-07

    In previous reports, Marrero-Ponce et al. proposed algebraic formalisms for characterizing topological (2D) and chiral (2.5D) molecular features through atom- and bond-based ToMoCoMD-CARDD (acronym for Topological Molecular Computational Design-Computer Aided Rational Drug Design) molecular descriptors. These MDs codify molecular information based on the bilinear, quadratic and linear algebraic forms and the graph-theoretical electronic-density and edge-adjacency matrices in order to consider atom- and bond-based relations, respectively. These MDs have been successfully applied in the screening of chemical compounds of different therapeutic applications ranging from antimalarials, antibacterials, tyrosinase inhibitors and so on. To compute these MDs, a computational program with the same name was initially developed. However, this in house software barely offered the functionalities required in contemporary molecular modeling tasks, in addition to the inherent limitations that made its usability impractical. Therefore, the present manuscript introduces the QuBiLS-MAS (acronym for Quadratic, Bilinear and N-Linear mapS based on graph-theoretic electronic-density Matrices and Atomic weightingS) software designed to compute topological (0-2.5D) molecular descriptors based on bilinear, quadratic and linear algebraic forms for atom- and bond-based relations. The QuBiLS-MAS module was designed as standalone software, in which extensions and generalizations of the former ToMoCoMD-CARDD 2D-algebraic indices are implemented, considering the following aspects: (a) two new matrix normalization approaches based on double-stochastic and mutual probability formalisms; (b) topological constraints (cut-offs) to take into account particular inter-atomic relations; (c) six additional atomic properties to be used as weighting schemes in the calculation of the molecular vectors; (d) four new local-fragments to consider molecular regions of interest; (e) number of lone-pair electrons in

  3. Investigation of an Alternative Fuel Form for the Liquid Salt Cooled Very High Temperature Reactor (LS-VHTR)

    International Nuclear Information System (INIS)

    Casino, William A. Jr.

    2006-01-01

    Much of the recent studies investigating the use of liquid salts as reactor coolants have utilized a core configuration of graphite prismatic fuel block assemblies with TRISO particles embedded into cylindrical fuel compacts arranged in a triangular pitch lattice. Although many calculations have been performed for this fuel form in gas cooled reactors, it would be instructive to investigate whether an alternative fuel form may yield improved performance for the liquid salt-cooled Very High Temperature Reactor (LS-VHTR). This study investigates how variations in the fuel form will impact the performance of the LS-VHTR during normal and accident conditions and compares the results with a similar analysis that was recently completed for a LS-VHTR core made up of prismatic block fuel. (author)

  4. Spread of CTX-M-type ESßLs in isolates of E. coli from long-term care and rehabilitation facilities in Northern Italy

    Directory of Open Access Journals (Sweden)

    Elisabetta Nucleo

    2008-09-01

    Full Text Available During the period March 2003 – May 2004 at the Laboratory of Clinical Microbiology “Redaelli” LTCRF in Milan, Italy, a total of 529 E. coli, obtained from inpatients of 3 different Long Term Care Rehabilitation Facilities (LTCRFs in Northern Italy, were processed and 77 ESßLs producers (14.5% were identified by Vitek System. The results were confirmed by double-disk synergy test with tazobactam (TZP. 61/77 isolates were characterized by higher levels of resistance to cefotaxime (CTX than to ceftazidime (CAZ. (ß-lactamase production was investigated by analytical isoelectric focusing (IEF coupled with a bioassay and showed multiple (ß-lactamase bands including one enzyme with pI 8.4 that, in a bioassay, was more active on CTX,ATM than on CAZ. The presence of (ß-lactamase genes was investigated by colony blot hybridization and by PCR amplification of blaTEM, blaSHV and blaCTX-M alleles. 43/61 isolates produced both TEM-1 and CTX-M-type enzymes, 14/61 expressed only CTX-M-type while in 4 cases were found blaCTX-M, blaTEM and blaSHV genes.The remainders (16/77, characterized by high levels of resistance to both CTX and CAZ, produced TEM-1 and SHV-5 enzymes (1/16 and TEM type ESßLs (15/16. Conjugation experiments, performed in liquid medium, confermed that the ESßLs determinants were transferable. Pulsed-field gel electrophoresis profiles of genomic DNA, digested with NotI, were analysed and revealed clonal heterogeneity. Our work confirms the emergence of CTX-M-type enzymes and their spread in Northern Italy also in longterm care and rehabilitation facilities that may be an important reservoir of ES?L producing E. coli.

  5. Signal Simulation and Experimental Research on Acoustic Emission using LS-DYNA

    Directory of Open Access Journals (Sweden)

    Zhang Jianchao

    2015-09-01

    Full Text Available To calculate sound wave velocity, we performed the Hsu-Nielsen lead break experiment using the ANSYS/LS-DYNA finite element software. First, we identified the key problems in the finite element analysis, such as selecting the exciting force, dividing the grid density, and setting the calculation steps. Second, we established the finite element model of the sound wave transmission in a plate under the lead break simulation. Results revealed not only the transmission characteristics of the sound wave but also the simulation and calculation of the transmission velocity of the longitudinal and transverse waves through the time travel curve of the vibration velocity of the sound wave at various nodes. Finally, the Hsu-Nielsen lead break experiment was implemented. The results of the theoretical calculation and simulation analysis were consistent with the experimental results, thus demonstrating that the research method using the ANSYS/LS-DYNA software to simulate sound wave transmissions in acoustic emission experiments is feasible and effective.

  6. Multi-scale Material Parameter Identification Using LS-DYNA® and LS-OPT®

    Energy Technology Data Exchange (ETDEWEB)

    Stander, Nielen; Basudhar, Anirban; Basu, Ushnish; Gandikota, Imtiaz; Savic, Vesna; Sun, Xin; Choi, Kyoo Sil; Hu, Xiaohua; Pourboghrat, F.; Park, Taejoon; Mapar, Aboozar; Kumar, Shavan; Ghassemi-Armaki, Hassan; Abu-Farha, Fadi

    2015-09-14

    Test Ban Treaty of 1996 which banned surface testing of nuclear devices [1]. This had the effect that experimental work was reduced from large scale tests to multiscale experiments to provide material models with validation at different length scales. In the subsequent years industry realized that multi-scale modeling and simulation-based design were transferable to the design optimization of any structural system. Horstemeyer [1] lists a number of advantages of the use of multiscale modeling. Among these are: the reduction of product development time by alleviating costly trial-and-error iterations as well as the reduction of product costs through innovations in material, product and process designs. Multi-scale modeling can reduce the number of costly large scale experiments and can increase product quality by providing more accurate predictions. Research tends to be focussed on each particular length scale, which enhances accuracy in the long term. This paper serves as an introduction to the LS-OPT and LS-DYNA methodology for multi-scale modeling. It mainly focuses on an approach to integrate material identification using material models of different length scales. As an example, a multi-scale material identification strategy, consisting of a Crystal Plasticity (CP) material model and a homogenized State Variable (SV) model, is discussed and the parameter identification of the individual material models of different length scales is demonstrated. The paper concludes with thoughts on integrating the multi-scale methodology into the overall vehicle design.

  7. A quantization scheme for scale-invariant pure gauge theories

    International Nuclear Information System (INIS)

    Hortacsu, M.

    1988-01-01

    A scheme is suggested for the quantization of the recently proposed scale-invariant gauge theories in higher dimensions. The model is minimally coupled to a spinor field. Regularization algorithms are proposed. (orig.)

  8. Supersymmetric Regularization Two-Loop QCD Amplitudes and Coupling Shifts

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Lance

    2002-03-08

    We present a definition of the four-dimensional helicity (FDH) regularization scheme valid for two or more loops. This scheme was previously defined and utilized at one loop. It amounts to a variation on the standard 't Hooft-Veltman scheme and is designed to be compatible with the use of helicity states for ''observed'' particles. It is similar to dimensional reduction in that it maintains an equal number of bosonic and fermionic states, as required for preserving supersymmetry. Supersymmetry Ward identities relate different helicity amplitudes in supersymmetric theories. As a check that the FDH scheme preserves supersymmetry, at least through two loops, we explicitly verify a number of these identities for gluon-gluon scattering (gg {yields} gg) in supersymmetric QCD. These results also cross-check recent non-trivial two-loop calculations in ordinary QCD. Finally, we compute the two-loop shift between the FDH coupling and the standard {bar M}{bar S} coupling, {alpha}{sub s}. The FDH shift is identical to the one for dimensional reduction. The two-loop coupling shifts are then used to obtain the three-loop QCD {beta} function in the FDH and dimensional reduction schemes.

  9. Supersymmetric Regularization Two-Loop QCD Amplitudes and Coupling Shifts

    International Nuclear Information System (INIS)

    Dixon, Lance

    2002-01-01

    We present a definition of the four-dimensional helicity (FDH) regularization scheme valid for two or more loops. This scheme was previously defined and utilized at one loop. It amounts to a variation on the standard 't Hooft-Veltman scheme and is designed to be compatible with the use of helicity states for ''observed'' particles. It is similar to dimensional reduction in that it maintains an equal number of bosonic and fermionic states, as required for preserving supersymmetry. Supersymmetry Ward identities relate different helicity amplitudes in supersymmetric theories. As a check that the FDH scheme preserves supersymmetry, at least through two loops, we explicitly verify a number of these identities for gluon-gluon scattering (gg → gg) in supersymmetric QCD. These results also cross-check recent non-trivial two-loop calculations in ordinary QCD. Finally, we compute the two-loop shift between the FDH coupling and the standard MS coupling, α s . The FDH shift is identical to the one for dimensional reduction. The two-loop coupling shifts are then used to obtain the three-loop QCD β function in the FDH and dimensional reduction schemes

  10. Bacillus amyloliquefaciens L-S60 Reforms the Rhizosphere Bacterial Community and Improves Growth Conditions in Cucumber Plug Seedling

    Directory of Open Access Journals (Sweden)

    Yuxuan Qin

    2017-12-01

    Full Text Available Vegetable plug seedling has become the most important way to produce vegetable seedlings in China. This seedling method can significantly improve the quality and yield of vegetables compared to conventional methods. In the process of plug seedling, chemical fertilizers or pesticides are often used to improve the yield of the seedlings albeit with increasing concerns. Meanwhile, little is known about the impact of beneficial bacteria on the rhizosphere microbiota and the growth conditions of vegetables during plug seedling. In this study, we applied a culture-independent next-generation sequencing-based approach and investigated the impact of a plant beneficial bacterium, Bacillus amyloliquefaciens L-S60, on the composition and dynamics of rhizosphere microbiota and the growth conditions of cucumbers during plug seedling. Our results showed that application of L-S60 significantly altered the structure of the bacterial community associated with the cucumber seedling; presence of beneficial rhizosphere species such as Bacillus, Rhodanobacter, Paenibacillus, Pseudomonas, Nonomuraea, and Agrobacterium was higher upon L-S60 treatment than in the control group. We also measured the impact of L-S60 application on the physiological properties of the cucumber seedlings as well as the availability of main mineral elements in the seedling at different time points during the plug seedling. Results from those measurements indicated that L-S60 application promoted growth conditions of cucumber seedlings and that more available mineral elements were detected in the cucumber seedlings from the L-S60 treated group than from the control group. The findings in this study provided evidence for the beneficial effects of plant growth-promoting rhizosphere bacteria on the bacterial community composition and growth conditions of the vegetables during plug seedling.

  11. Hydrodynamics of Normal Atomic Gases with Spin-orbit Coupling.

    Science.gov (United States)

    Hou, Yan-Hua; Yu, Zhenhua

    2015-10-20

    Successful realization of spin-orbit coupling in atomic gases by the NIST scheme opens the prospect of studying the effects of spin-orbit coupling on many-body physics in an unprecedentedly controllable way. Here we derive the linearized hydrodynamic equations for the normal atomic gases of the spin-orbit coupling by the NIST scheme with zero detuning. We show that the hydrodynamics of the system crucially depends on the momentum susceptibilities which can be modified by the spin-orbit coupling. We reveal the effects of the spin-orbit coupling on the sound velocities and the dipole mode frequency of the gases by applying our formalism to the ideal Fermi gas. We also discuss the generalization of our results to other situations.

  12. Whole-genome sequencing of Bacillus velezensis LS69, a strain with a broad inhibitory spectrum against pathogenic bacteria.

    Science.gov (United States)

    Liu, Guoqiang; Kong, Yingying; Fan, Yajing; Geng, Ce; Peng, Donghai; Sun, Ming

    2017-05-10

    Bacillus velezensis LS69 was found to exhibit antagonistic activity against a diverse spectrum of pathogenic bacteria. It has one circular chromosome of 3,917,761bp with 3,643 open reading frames. Genome analysis identified ten gene clusters involved in nonribosomal synthesis of polyketides (macrolactin, bacillaene and difficidin), lipopeptides (surfactin, fengycin, bacilysin and iturin A) and bacteriocins (amylolysin and amylocyclicin). In addition, B. velezensis LS69 was found to contain a series of genes involved in enhancing plant growth and triggering plant immunity. Whole genome sequencing of Bacillus velezensis LS69 will provide a basis for elucidation of its biocontrol mechanisms and facilitate its applications in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Wave equations on a de Sitter fiber bundle. [Semiclassical wave function, bundle space, L-S coupling

    Energy Technology Data Exchange (ETDEWEB)

    Drechsler, W [Max-Planck-Institut fuer Physik und Astrophysik, Muenchen (F.R. Germany)

    1975-01-01

    A gauge theory of strong interaction is developed based on fields defined on a fiber bundle. The structural group of the bundle is taken to be the Lsub(4,1) de Sitter group. An internal variable xi, varying in the fiber over a space-time point x, is introduced as a means to describe - with the help of a semiclassical wave function psi(x,xi) defined on the bundle space - the internal structure of extended hadrons in a framework using differential geometric techniques. Three basic nonlinear wave equations for psi(x,xi) are established which are of integro-differential type. The nonlinear coupling terms in these de Sitter gauge invariant equations represent physically a generalized spin orbit coupling or a generalized spin coupling for the motion taking place in the fiber. The motivation for using a bigger space for the definition of hadronic matter wave functions as well as the implications of this geometric approach to strong interaction physics is discussed in detail, in particular with respect to the problem of hadronic constituents. The proposed fiber bundle formalism allows a dynamical description of extended structures for hadrons without implying the necessity of introducing any constituents.

  14. The Ne3LS Network, Quebec's initiative to evaluate the impact and promote a responsible and sustainable development of nanotechnology

    International Nuclear Information System (INIS)

    Endo, Charles-Anica; Emond, Claude; Battista, Renaldo; Parizeau, Marie-Helene; Beaudry, Catherine

    2011-01-01

    The spectacular progress made by nanosciences and nanotechnologies elicits as much hope and fear. Consequently, a great number of research and training initiatives on the ethical, environmental, economic, legal and social issues regarding nanotechnology development (Ne 3 LS) are emerging worldwide. In Quebec, Canada, a Task Force was mandated by NanoQuebec to conceive a Ne 3 LS research and training strategy to assess those issues. This Task Force brought together experts from universities, governments or industry working in nanosciences and nanotechnologies or in Ne 3 LS. Their resulting action plan, made public in November 2006, contained several recommendations, including the creation of a knowledge network (Ne 3 LS Network). In the following years, after consulting with numerous key players concerned with the possible impacts of nanosciences and nanotechnologies in Quebec, the Ne 3 LS Network was launched in January 2010 in partnership with the Fonds quebecois de la recherche sur la nature et les technologies, the Fonds quebecois de la recherche sur la societe et la culture and the Fonds de la recherche en sante du Quebec, NanoQuebec, the Institut de recherche Robert-Sauve en sante et en securite du travail as well as the University of Montreal. Its objectives are to 1) Foster the development of Ne 3 LS research activities (grants and fellowships); 2) Spearhead the Canadian and international Ne 3 LS network; 3) Take part in the training of researchers and experts; 4) Encourage the creation of interactive tools for the general public; 5) Facilitate collaboration between decision-makers and experts; 6) Involve the scientific community through a host of activities (symposium, conferences, thematic events); 7) Build multidisciplinary research teams to evaluate the impact of nanotechnology.

  15. A space-time lower-upper symmetric Gauss-Seidel scheme for the time-spectral method

    Science.gov (United States)

    Zhan, Lei; Xiong, Juntao; Liu, Feng

    2016-05-01

    The time-spectral method (TSM) offers the advantage of increased order of accuracy compared to methods using finite-difference in time for periodic unsteady flow problems. Explicit Runge-Kutta pseudo-time marching and implicit schemes have been developed to solve iteratively the space-time coupled nonlinear equations resulting from TSM. Convergence of the explicit schemes is slow because of the stringent time-step limit. Many implicit methods have been developed for TSM. Their computational efficiency is, however, still limited in practice because of delayed implicit temporal coupling, multiple iterative loops, costly matrix operations, or lack of strong diagonal dominance of the implicit operator matrix. To overcome these shortcomings, an efficient space-time lower-upper symmetric Gauss-Seidel (ST-LU-SGS) implicit scheme with multigrid acceleration is presented. In this scheme, the implicit temporal coupling term is split as one additional dimension of space in the LU-SGS sweeps. To improve numerical stability for periodic flows with high frequency, a modification to the ST-LU-SGS scheme is proposed. Numerical results show that fast convergence is achieved using large or even infinite Courant-Friedrichs-Lewy (CFL) numbers for unsteady flow problems with moderately high frequency and with the use of moderately high numbers of time intervals. The ST-LU-SGS implicit scheme is also found to work well in calculating periodic flow problems where the frequency is not known a priori and needed to be determined by using a combined Fourier analysis and gradient-based search algorithm.

  16. The effect of a coupling field on the entanglement dynamics of a three-level atom

    International Nuclear Information System (INIS)

    Mortezapour, Ali; Mahmoudi, Mohammad; Abedi, Majid; Khajehpour, M R H

    2011-01-01

    The effect of a coupling laser field on the entanglement of a three-level quantum system and its spontaneous emission is investigated via the reduced quantum entropy. We consider two schemes: the upper- and lower-level couplings. By calculating the degree of entanglement (DEM) for both systems, it is shown that the entanglement between the atom and its spontaneous emission can be controlled by the coupling laser field. This field, however, affects the entanglement differently in the two schemes; it is only the lower-level coupling scheme that shows a non-zero steady state DEM which can be controlled by the intensity and detuning of the coupling laser field.

  17. The effect of a coupling field on the entanglement dynamics of a three-level atom

    Energy Technology Data Exchange (ETDEWEB)

    Mortezapour, Ali; Mahmoudi, Mohammad [Physics Department, Zanjan University, PO Box 45195-313, Zanjan (Iran, Islamic Republic of); Abedi, Majid; Khajehpour, M R H, E-mail: mahmoudi@iasbs.ac.ir, E-mail: pour@iasbs.ac.ir [Institute for Advanced Studies in Basic Sciences, PO Box 45195-159, Zanjan (Iran, Islamic Republic of)

    2011-04-28

    The effect of a coupling laser field on the entanglement of a three-level quantum system and its spontaneous emission is investigated via the reduced quantum entropy. We consider two schemes: the upper- and lower-level couplings. By calculating the degree of entanglement (DEM) for both systems, it is shown that the entanglement between the atom and its spontaneous emission can be controlled by the coupling laser field. This field, however, affects the entanglement differently in the two schemes; it is only the lower-level coupling scheme that shows a non-zero steady state DEM which can be controlled by the intensity and detuning of the coupling laser field.

  18. A New European Slope Length and Steepness Factor (LS-Factor for Modeling Soil Erosion by Water

    Directory of Open Access Journals (Sweden)

    Panos Panagos

    2015-04-01

    Full Text Available The Universal Soil Loss Equation (USLE model is the most frequently used model for soil erosion risk estimation. Among the six input layers, the combined slope length and slope angle (LS-factor has the greatest influence on soil loss at the European scale. The S-factor measures the effect of slope steepness, and the L-factor defines the impact of slope length. The combined LS-factor describes the effect of topography on soil erosion. The European Soil Data Centre (ESDAC developed a new pan-European high-resolution soil erosion assessment to achieve a better understanding of the spatial and temporal patterns of soil erosion in Europe. The LS-calculation was performed using the original equation proposed by Desmet and Govers (1996 and implemented using the System for Automated Geoscientific Analyses (SAGA, which incorporates a multiple flow algorithm and contributes to a precise estimation of flow accumulation. The LS-factor dataset was calculated using a high-resolution (25 m Digital Elevation Model (DEM for the whole European Union, resulting in an improved delineation of areas at risk of soil erosion as compared to lower-resolution datasets. This combined approach of using GIS software tools with high-resolution DEMs has been successfully applied in regional assessments in the past, and is now being applied for first time at the European scale.

  19. Quadratically convergent MCSCF scheme using Fock operators

    International Nuclear Information System (INIS)

    Das, G.

    1981-01-01

    A quadratically convergent formulation of the MCSCF method using Fock operators is presented. Among its advantages the present formulation is quadratically convergent unlike the earlier ones based on Fock operators. In contrast to other quadratically convergent schemes as well as the one based on generalized Brillouin's theorem, this method leads easily to a hybrid scheme where the weakly coupled orbitals (such as the core) are handled purely by Fock equations, while the rest of the orbitals are treated by a quadratically convergent approach with a truncated virtual space obtained by the use of the corresponding Fock equations

  20. Simple Detection of Large InDeLS by DHPLC: The ACE Gene as a Model

    Directory of Open Access Journals (Sweden)

    Renata Guedes Koyama

    2008-01-01

    Full Text Available Insertion-deletion polymorphism (InDeL is the second most frequent type of genetic variation in the human genome. For the detection of large InDeLs, researchers usually resort to either PCR gel analysis or RFLP, but these are time consuming and dependent on human interpretation. Therefore, a more efficient method for genotyping this kind of genetic variation is needed. In this report, we describe a method that can detect large InDeLs by DHPLC (denaturating high-performance liquid chromatography using the angiotensin-converting enzyme (ACE gene I/D polymorphism as a model. The InDeL targeted in this study is characterized by a 288 bp Alu element insertion (I. We used DHPLC at nondenaturating conditions to analyze the PCR product with a flow through the chromatographic column under two different gradients based on the differences between D and I sequences. The analysis described is quick and easy, making this technique a suitable and efficient means for DHPLC users to screen InDeLs in genetic epidemiological studies.

  1. Lifting scheme-based method for joint coding 3D stereo digital cinema with luminace correction and optimized prediction

    Science.gov (United States)

    Darazi, R.; Gouze, A.; Macq, B.

    2009-01-01

    Reproducing a natural and real scene as we see in the real world everyday is becoming more and more popular. Stereoscopic and multi-view techniques are used for this end. However due to the fact that more information are displayed requires supporting technologies such as digital compression to ensure the storage and transmission of the sequences. In this paper, a new scheme for stereo image coding is proposed. The original left and right images are jointly coded. The main idea is to optimally exploit the existing correlation between the two images. This is done by the design of an efficient transform that reduces the existing redundancy in the stereo image pair. This approach was inspired by Lifting Scheme (LS). The novelty in our work is that the prediction step is been replaced by an hybrid step that consists in disparity compensation followed by luminance correction and an optimized prediction step. The proposed scheme can be used for lossless and for lossy coding. Experimental results show improvement in terms of performance and complexity compared to recently proposed methods.

  2. Multi-scale Material Parameter Identification Using LS-DYNA® and LS-OPT®

    Energy Technology Data Exchange (ETDEWEB)

    Stander, Nielen [Livermore Software Technology Corporation, CA (United States); Basudhar, Anirban [Livermore Software Technology Corporation, CA (United States); Basu, Ushnish [Livermore Software Technology Corporation, CA (United States); Gandikota, Imtiaz [Livermore Software Technology Corporation, CA (United States); Savic, Vesna [General Motors, Flint, MI (United States); Sun, Xin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hu, XiaoHua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pourboghrat, Farhang [The Ohio State Univ., Columbus, OH (United States); Park, Taejoon [The Ohio State Univ., Columbus, OH (United States); Mapar, Aboozar [Michigan State Univ., East Lansing, MI (United States); Kumar, Sharvan [Brown Univ., Providence, RI (United States); Ghassemi-Armaki, Hassan [Brown Univ., Providence, RI (United States); Abu-Farha, Fadi [Clemson Univ., SC (United States)

    2015-06-15

    Ever-tightening regulations on fuel economy and carbon emissions demand continual innovation in finding ways for reducing vehicle mass. Classical methods for computational mass reduction include sizing, shape and topology optimization. One of the few remaining options for weight reduction can be found in materials engineering and material design optimization. Apart from considering different types of materials by adding material diversity, an appealing option in automotive design is to engineer steel alloys for the purpose of reducing thickness while retaining sufficient strength and ductility required for durability and safety. Such a project was proposed and is currently being executed under the auspices of the United States Automotive Materials Partnership (USAMP) funded by the Department of Energy. Under this program, new steel alloys (Third Generation Advanced High Strength Steel or 3GAHSS) are being designed, tested and integrated with the remaining design variables of a benchmark vehicle Finite Element model. In this project the principal phases identified are (i) material identification, (ii) formability optimization and (iii) multi-disciplinary vehicle optimization. This paper serves as an introduction to the LS-OPT methodology and therefore mainly focuses on the first phase, namely an approach to integrate material identification using material models of different length scales. For this purpose, a multi-scale material identification strategy, consisting of a Crystal Plasticity (CP) material model and a Homogenized State Variable (SV) model, is discussed and demonstrated. The paper concludes with proposals for integrating the multi-scale methodology into the overall vehicle design.

  3. Xerostomia Quality of Life Scale (XeQoLS) questionnaire: validation of Italian version in head and neck cancer patients.

    Science.gov (United States)

    Lastrucci, Luciana; Bertocci, Silvia; Bini, Vittorio; Borghesi, Simona; De Majo, Roberta; Rampini, Andrea; Gennari, Pietro Giovanni; Pernici, Paola

    2018-01-01

    To translate the Xerostomia Quality-of-Life Scale (XeQoLS) into Italian language (XeQoLS-IT). Xerostomia is the most relevant acute and late toxicity in patients with head and neck cancer treated with radiotherapy (RT). Patient-reported outcome (PRO) instruments are subjective report on patient perception of health status. The XeQoLS consists of 15 items and measures the impact of salivary gland dysfunction and xerostomia on the four major domains of oral health-related QoL. The XeQoLS-IT was created through a linguistic validation multi-step process: forward translation (TF), backward translation (TB) and administration of the questionnaire to 35 Italian patients with head and neck cancer. Translation was independently carried out by two radiation oncologists who were Italian native speakers. The two versions were compared and adapted to obtain a reconciled version, version 1 (V1). V1 was translated back into English by an Italian pro skilled in teaching English. After review of discrepancies and choice of the most appropriate wording for clarity and similarity to the original, version 2 (V2) was reached by consensus. To evaluate version 2, patients completed the XeQoLS-IT questionnaire and also underwent a cognitive debriefing. The questionnaire was considered simple by the patients. The clarity of the instructions and the easiness to answer questions had a mean value of 4.5 (± 0.71) on a scale from 1 to 5. A valid multi-step process led to the creation of the final version of the XeQoLS-IT, a suitable instrument for the perception of xerostomia in patients treated with RT.

  4. Synchronization of coupled different chaotic FitzHugh-Nagumo neurons with unknown parameters under communication-direction-dependent coupling.

    Science.gov (United States)

    Iqbal, Muhammad; Rehan, Muhammad; Khaliq, Abdul; Saeed-ur-Rehman; Hong, Keum-Shik

    2014-01-01

    This paper investigates the chaotic behavior and synchronization of two different coupled chaotic FitzHugh-Nagumo (FHN) neurons with unknown parameters under external electrical stimulation (EES). The coupled FHN neurons of different parameters admit unidirectional and bidirectional gap junctions in the medium between them. Dynamical properties, such as the increase in synchronization error as a consequence of the deviation of neuronal parameters for unlike neurons, the effect of difference in coupling strengths caused by the unidirectional gap junctions, and the impact of large time-delay due to separation of neurons, are studied in exploring the behavior of the coupled system. A novel integral-based nonlinear adaptive control scheme, to cope with the infeasibility of the recovery variable, for synchronization of two coupled delayed chaotic FHN neurons of different and unknown parameters under uncertain EES is derived. Further, to guarantee robust synchronization of different neurons against disturbances, the proposed control methodology is modified to achieve the uniformly ultimately bounded synchronization. The parametric estimation errors can be reduced by selecting suitable control parameters. The effectiveness of the proposed control scheme is illustrated via numerical simulations.

  5. A real nonlinear integrable couplings of continuous soliton hierarchy and its Hamiltonian structure

    International Nuclear Information System (INIS)

    Yu Fajun

    2011-01-01

    Some integrable coupling systems of existing papers are linear integrable couplings. In the Letter, beginning with Lax pairs from special non-semisimple matrix Lie algebras, we establish a scheme for constructing real nonlinear integrable couplings of continuous soliton hierarchy. A direct application to the AKNS spectral problem leads to a novel nonlinear integrable couplings, then we consider the Hamiltonian structures of nonlinear integrable couplings of AKNS hierarchy with the component-trace identity. - Highlights: → We establish a scheme to construct real nonlinear integrable couplings. → We obtain a novel nonlinear integrable couplings of AKNS hierarchy. → Hamiltonian structure of nonlinear integrable couplings AKNS hierarchy is presented.

  6. UFOs in the LHC after LS1

    International Nuclear Information System (INIS)

    Baer, T.; Barnes, M.J.; Carlier, E.; Cerutti, F.; Dehning, B.; Ducimetiere, L.; Ferrari, A.; Garrel, N.; Gerardin, A.; Goddard, B.; Holzer, E.B.; Jackson, S.; Jimenez, J.M.; Kain, V.; Lechner, A.; Mertens, V.; Misiowiec, M.; Moron Ballester, R.; Nebot del Busto, E.; Norderhaug Drosdal, L.; Nordt, A.; Uythoven, J.; Velghe, B.; Vlachoudis, V.; Wenninger, J.; Zamantzas, C.; Zimmermann, F.; Fuster Martinez, N.

    2012-01-01

    UFOs (Unidentified Falling Objects) are potentially a major luminosity limitation for nominal LHC operation. With large-scale increases of the BLM thresholds, their impact on LHC availability was mitigated in the second half of 2011. For higher beam energy and lower magnet quench limits, the problem is expected to be considerably worse, though. Therefore, in 2011, the diagnostics for UFO events were significantly improved, dedicated experiments and measurements in the LHC and in the laboratory were made and complemented by FLUKA simulations and theoretical studies. In this paper, the state of knowledge is summarized and extrapolations for LHC operation after LS1 are presented. Mitigation strategies are proposed and related tests and measures for 2012 are specified. (authors)

  7. UFOs in the LHC after LS1

    CERN Document Server

    Baer, T; Carlier, E; Cerutti, F; Dehning, B; Ducimetière, L; Ferrari, A; Garrel, N; Gérardin, A; Goddard, B; Holzer, E B; Jackson, S; Jimenez, J M; Kain, V; Lechner, A; Mertens, V; Misiowiec, M; Morón Ballester, R; Nebot del Busto, E; Norderhaug Drosdal, L; Nordt, A; Uythoven, J; Velghe, B; Vlachoudis, V; Wenninger, J; Zamantzas, C; Zimmermann, F; Fuster Martinez, N

    2012-01-01

    UFOs (Unidentified Falling Objects) are potentially a major luminosity limitation for nominal LHC operation. With large-scale increases of the BLM thresholds, their impact on LHC availability was mitigated in the second half of 2011. For higher beam energy and lower magnet quench limits, the problem is expected to be considerably worse, though. Therefore, in 2011, the diagnostics for UFO events were significantly improved, dedicated experiments and measurements in the LHC and in the laboratory were made and complemented by FLUKA simulations and theoretical studies. In this paper, the state of knowledge is summarized and extrapolations for LHC operation after LS1 are presented. Mitigation strategies are proposed and related tests and measures for 2012 are specified.

  8. ABCB1 (P-glycoprotein) reduces bacterial attachment to human gastrointestinal LS174T epithelial cells.

    Science.gov (United States)

    Crowe, Andrew; Bebawy, Mary

    2012-08-15

    The aim of this project was to show elevated P-glycoprotein (P-gp) expression decreasing bacterial association with LS174T human gastrointestinal cells, and that this effect could be reversed upon blocking functional P-gp efflux. Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Lactobacillus acidophilus and numerous strains of Escherichia coli, from commensal to enteropathogenic and enterohaemorrhagic strains (O157:H7) were fluorescently labelled and incubated on LS174T cultures either with or without P-gp amplification using rifampicin. PSC-833 was used as a potent functional P-gp blocking agent. Staphylococcus and Pseudomonas displayed the greatest association with the LS174T cells. Surprisingly, lactobacilli retained more fluorescence than enteropathogenic-E. coli in this system. Irrespective of attachment differences between the bacterial species, the increase in P-gp protein expression decreased bacterial fluorescence by 25-30%. This included the GFP-labelled E. coli, and enterohaemorrhagic E. coli (O157:H7). Blocking P-gp function through the co-administration of PSC-833 increased the amount of bacteria associated with P-gp expressing LS174T cells back to control levels. As most bacteria were affected to the same degree, irrespective of pathogenicity, it is unlikely that P-gp has a direct influence on adhesion of bacteria, and instead P-gp may be playing an indirect role by secreting a bank of endogenous factors or changing the local environment to one less suited to bacterial growth in general. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  9. Galilean invariant lattice Boltzmann scheme for natural convection on square and rectangular lattices

    NARCIS (Netherlands)

    Sman, van der R.G.M.

    2006-01-01

    In this paper we present lattice Boltzmann (LB) schemes for convection diffusion coupled to fluid flow on two-dimensional rectangular lattices. Via inverse Chapman-Enskog analysis of LB schemes including source terms, we show that for consistency with physics it is required that the moments of the

  10. LS1 “First Long Shutdown of LHC and its Injector Chains”

    CERN Multimedia

    Foraz, K; Barberan, M; Bernardini, M; Coupard, J; Gilbert, N; Hay, D; Mataguez, S; McFarlane, D

    2014-01-01

    The LHC and its Injectors were stopped in February 2013, in order to maintain, consolidate and upgrade the different equipment of the accelerator chain, with the goal of achieving LHC operation at the design energy of 14 TeV in the centre-of-mass. Prior to the start of this First Long Shutdown (LS1), a major effort of preparation was performed in order to optimize the schedule and the use of resources across the different machines, with the aim of resuming LHC physics in early 2015. The rest of the CERN complex will restart beam operation in the second half of 2014. This paper presents the schedule of the LS1, describes the organizational set-up for the coordination of the works, the main activities, the different main milestones, which have been achieved so far, and the decisions taken in order to mitigate the issues encountered.

  11. PDF fit in the fixed-flavour-number scheme

    International Nuclear Information System (INIS)

    Alekhin, S.; Bluemlein, J.; Moch, S.

    2012-02-01

    We discuss the heavy-quark contribution to deep inelastic scattering in the scheme with n f =3;4;5 fixed flavors. Based on the recent ABM11 PDF analysis of world data for deep-inelastic scattering and fixed-target data for the Drell-Yan process with the running-mass definition for heavy quarks we show that fixed flavor number scheme is sufficient for describing the deep-inelastic-scattering data in the entire kinematic range. We compare with other PDF sets and comment on the implications for measuring the strong coupling constant α s (M Z ).

  12. LS1 to LHC Report: LHC key handed back to Operations

    CERN Multimedia

    CERN Bulletin

    2015-01-01

    This week, after 23 months of hard work involving about 1000 people every day, the key to the LHC was symbolically handed back to the Operations team. The first long shutdown is over and the machine is getting ready for a restart that will bring its beam to full energy in early spring.   Katy Foraz, LS1 activities coordinator, symbolically hands the LHC key to the operations team, represented, left to right, by Jorg Wenninger, Mike Lamont and Mirko Pojer. All the departments, all the machines and all the experimental areas were involved in the first long shutdown of the LHC that began in February 2013. Over the last two years, the Bulletin has closely followed  all the work and achievements that had been carefully included in the complex general schedule drawn up and managed by the team led by Katy Foraz from the Engineering Department. “The work on the schedule began two years before the start of LS1 and one of the first things we realised was that there was no commercial...

  13. Analytical scheme calculations of angular momentum coupling and recoupling coefficients

    Science.gov (United States)

    Deveikis, A.; Kuznecovas, A.

    2007-03-01

    We investigate the Scheme programming language opportunities to analytically calculate the Clebsch-Gordan coefficients, Wigner 6j and 9j symbols, and general recoupling coefficients that are used in the quantum theory of angular momentum. The considered coefficients are calculated by a direct evaluation of the sum formulas. The calculation results for large values of quantum angular momenta were compared with analogous calculations with FORTRAN and Java programming languages.

  14. Analytical scheme calculations of angular momentum coupling and recoupling coefficients

    International Nuclear Information System (INIS)

    Deveikis, A.; Kuznecovas, A.

    2007-01-01

    We investigate the Scheme programming language opportunities to analytically calculate the Clebsch-Gordan coefficients, Wigner 6j and 9j symbols, and general recoupling coefficients that are used in the quantum theory of angular momentum. The considered coefficients are calculated by a direct evaluation of the sum formulas. The calculation results for large values of quantum angular momenta were compared with analogous calculations with FORTRAN and Java programming languages

  15. Coupling Functions Enable Secure Communications

    Science.gov (United States)

    Stankovski, Tomislav; McClintock, Peter V. E.; Stefanovska, Aneta

    2014-01-01

    Secure encryption is an essential feature of modern communications, but rapid progress in illicit decryption brings a continuing need for new schemes that are harder and harder to break. Inspired by the time-varying nature of the cardiorespiratory interaction, here we introduce a new class of secure communications that is highly resistant to conventional attacks. Unlike all earlier encryption procedures, this cipher makes use of the coupling functions between interacting dynamical systems. It results in an unbounded number of encryption key possibilities, allows the transmission or reception of more than one signal simultaneously, and is robust against external noise. Thus, the information signals are encrypted as the time variations of linearly independent coupling functions. Using predetermined forms of coupling function, we apply Bayesian inference on the receiver side to detect and separate the information signals while simultaneously eliminating the effect of external noise. The scheme is highly modular and is readily extendable to support different communications applications within the same general framework.

  16. Extension of a GIS procedure for calculating the RUSLE equation LS factor

    NARCIS (Netherlands)

    Zhang, H.; Yang, Q.; Li, R.; Liu, Q.; Moore, D.; He, P.; Ritsema, C.J.; Geissen, V.

    2013-01-01

    The Universal Soil Loss Equation (USLE) and revised USLE (RUSLE) are often used to estimate soil erosion at regional landscape scales, however a major limitation is the difficulty in extracting the LS factor. The geographic information system-based (GIS-based) methods which have been developed for

  17. The successful completion of LS1, consolidation and preparations for the future

    CERN Multimedia

    Antonella Del Rosso

    2014-01-01

    For CERN’s Technology (TE) Department, success in LS1 is more important than finishing. In other words, the aim is to reach the finish line having maintained the highest standards of safety, quality and performance. Other challenges need to be faced too, before, during and after LS1, and the Department always approaches them with optimism. The new Department Head tells us how his 750 colleagues work to keep the Laboratory at the cutting edge of high-energy physics technology.   José Miguel Jiménez. “We can only grow once we’ve stabilised our base.” The message presented by José Miguel Jiménez, who stepped into the role of TE Department Head in January 2014, is clear, as are his priorities going forward: “The Technology Department needs to be consolidated in terms of both its personnel and its assembly and test infrastructures, some of which are unique.” The TE Department is tasked with pr...

  18. ASTROPHYSICAL PARAMETERS OF LS 2883 AND IMPLICATIONS FOR THE PSR B1259-63 GAMMA-RAY BINARY

    International Nuclear Information System (INIS)

    Negueruela, Ignacio; Lorenzo, Javier; Ribo, Marc; Herrero, Artemio; Khangulyan, Dmitry; Aharonian, Felix A.

    2011-01-01

    Only a few binary systems with compact objects display TeV emission. The physical properties of the companion stars represent basic input for understanding the physical mechanisms behind the particle acceleration, emission, and absorption processes in these so-called gamma-ray binaries. Here we present high-resolution and high signal-to-noise optical spectra of LS 2883, the Be star forming a gamma-ray binary with the young non-accreting pulsar PSR B1259-63, showing it to rotate faster and be significantly earlier and more luminous than previously thought. Analysis of the interstellar lines suggests that the system is located at the same distance as (and thus is likely a member of) Cen OB1. Taking the distance to the association, d = 2.3 kpc, and a color excess of E(B - V) = 0.85 for LS 2883 results in M V ∼ -4.4. Because of fast rotation, LS 2883 is oblate (R eq ≅ 9.7 R sun and R pole ≅ 8.1 R sun ) and presents a temperature gradient (T eq ∼ 27,500 K, log g eq = 3.7; T pole ∼ 34,000 K, log g pole = 4.1). If the star did not rotate, it would have parameters corresponding to a late O-type star. We estimate its luminosity at log(L * /L sun ) ≅ 4.79 and its mass at M * ∼ 30 M sun . The mass function then implies an inclination of the binary system i orb ∼ 23 0 , slightly smaller than previous estimates. We discuss the implications of these new astrophysical parameters of LS 2883 for the production of high-energy and very high-energy gamma rays in the PSR B1259-63/LS 2883 gamma-ray binary system. In particular, the stellar properties are very important for prediction of the line-like bulk Comptonization component from the unshocked ultrarelativistic pulsar wind.

  19. Minimal coupling schemes in N-body reaction theory

    International Nuclear Information System (INIS)

    Picklesimer, A.; Tandy, P.C.; Thaler, R.M.

    1982-01-01

    A new derivation of the N-body equations of Bencze, Redish, and Sloan is obtained through the use of Watson-type multiple scattering techniques. The derivation establishes an intimate connection between these partition-labeled N-body equations and the particle-labeled Rosenberg equations. This result yields new insight into the implicit role of channel coupling in, and the minimal dimensionality of, the partition-labeled equations

  20. Mixed coherent states in coupled chaotic systems: Design of secure wireless communication

    Science.gov (United States)

    Vigneshwaran, M.; Dana, S. K.; Padmanaban, E.

    2016-12-01

    A general coupling design is proposed to realize a mixed coherent (MC) state: coexistence of complete synchronization, antisynchronization, and amplitude death in different pairs of similar state variables of the coupled chaotic system. The stability of coupled system is ensured by the Lyapunov function and a scaling of each variable is also separately taken care of. When heterogeneity as a parameter mismatch is introduced in the coupled system, the coupling function facilitates to retain its coherence and displays the global stability with renewed scaling factor. Robust synchronization features facilitated by a MC state enable to design a dual modulation scheme: binary phase shift key (BPSK) and parameter mismatch shift key (PMSK), for secure data transmission. Two classes of decoders (coherent and noncoherent) are discussed, the noncoherent decoder shows better performance over the coherent decoder, mostly a noncoherent demodulator is preferred in biological implant applications. Both the modulation schemes are demonstrated numerically by using the Lorenz oscillator and the BPSK scheme is demonstrated experimentally using radio signals.

  1. Another scheme for quantization of scale invariant gauge theories

    International Nuclear Information System (INIS)

    Hortacsu, M.

    1987-10-01

    A new scheme is proposed for the quantization of scale invariant gauge theories for all even dimensions when they are minimally coupled to a spinor field. A cut-off procedure suggests an algorithm which may regularize the theory. (author). 10 refs

  2. Biosphere-Atmosphere Transfer Scheme (BATS) version le as coupled to the NCAR community climate model. Technical note. [NCAR (National Center for Atmospheric Research)

    Energy Technology Data Exchange (ETDEWEB)

    Dickinson, R.E.; Henderson-Sellers, A.; Kennedy, P.J.

    1993-08-01

    A comprehensive model of land-surface processes has been under development suitable for use with various National Center for Atmospheric Research (NCAR) General Circulation Models (GCMs). Special emphasis has been given to describing properly the role of vegetation in modifying the surface moisture and energy budgets. The result of these efforts has been incorporated into a boundary package, referred to as the Biosphere-Atmosphere Transfer Scheme (BATS). The current frozen version, BATS1e is a piece of software about four thousand lines of code that runs as an offline version or coupled to the Community Climate Model (CCM).

  3. Electrodialytic extraction of heavy metals from Greenlandic MSWI fly ash as a function of remediation time and L/S ratio

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2013-01-01

    , where the fly ash was suspended in distilled water in different liquid to solid (L/S) ratios. Remediation times of 7 and 14 days were tested and the current strength was 50 mA in all experiments. The highest removal was seen when an acidic pH in the fly ash suspension was obtained. In an experiment...... lasting 14 days with L/S 10, up to 60 % Cd, 45 % Zn, 20 % Ni and Ba was removed. Regardless of the remediation time and L/S ratio, the fraction of soluble Ba, Cr and Pb decreased due to the electrodialytic remediation. The electrodialytic remediation method showed potential as a treatment method...

  4. Analysis of a discrete element method and coupling with a compressible fluid flow method

    International Nuclear Information System (INIS)

    Monasse, L.

    2011-01-01

    This work aims at the numerical simulation of compressible fluid/deformable structure interactions. In particular, we have developed a partitioned coupling algorithm between a Finite Volume method for the compressible fluid and a Discrete Element method capable of taking into account fractures in the solid. A survey of existing fictitious domain methods and partitioned algorithms has led to choose an Embedded Boundary method and an explicit coupling scheme. We first showed that the Discrete Element method used for the solid yielded the correct macroscopic behaviour and that the symplectic time-integration scheme ensured the preservation of energy. We then developed an explicit coupling algorithm between a compressible inviscid fluid and an un-deformable solid. Mass, momentum and energy conservation and consistency properties were proved for the coupling scheme. The algorithm was then extended to the coupling with a deformable solid, in the form of a semi implicit scheme. Finally, we applied this method to unsteady inviscid flows around moving structures: comparisons with existing numerical and experimental results demonstrate the excellent accuracy of our method. (author) [fr

  5. Synthesis and characterization of sulfonate polystyrene-lignosulfonate-alumina (SPS-LS-Al{sub 2}O{sub 3}) polyblends as electrolyte membranes for fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Gonggo, Siang Tandi, E-mail: standigonggo@yahoo.com [Chemistry Research Groups, Faculty of Teacher Training and Educational Sciences, Tadulako University (Indonesia)

    2015-09-30

    The new type of electrolyte membrane materials has been prepared by blend sulfonated polystyrene (SPS), lignosulfonate (LS), and alumina (SPS-LS-Al{sub 2}O{sub 3}) by casting polymer solution. The resulting polymer electrolyte membranes were then characterized by functional groups analysis, mechanical properties, water uptake, ion exchange capacity, and proton conductivity. SPS-LS-Al{sub 2}O{sub 3} membranes with alumina composition various have been proven qualitatively by analysis of functional groups. Increasing the Al{sub 2}O{sub 3} ratio resulted in higher ion exchange capacity (IEC), mechanical strength and proton conductivity, but water uptake decreased. The SPS-LS-Al{sub 2}O{sub 3} blend showed higher proton conductivity than Nafion 117.

  6. A Time Marching Scheme for Solving Volume Integral Equations on Nonlinear Scatterers

    KAUST Repository

    Bagci, Hakan

    2015-01-07

    Transient electromagnetic field interactions on inhomogeneous penetrable scatterers can be analyzed by solving time domain volume integral equations (TDVIEs). TDVIEs are oftentimes solved using marchingon-in-time (MOT) schemes. Unlike finite difference and finite element schemes, MOT-TDVIE solvers require discretization of only the scatterers, do not call for artificial absorbing boundary conditions, and are more robust to numerical phase dispersion. On the other hand, their computational cost is high, they suffer from late-time instabilities, and their implicit nature makes incorporation of nonlinear constitutive relations more difficult. Development of plane-wave time-domain (PWTD) and FFT-based schemes has significantly reduced the computational cost of the MOT-TDVIE solvers. Additionally, latetime instability problem has been alleviated for all practical purposes with the development of accurate integration schemes and specially designed temporal basis functions. Addressing the third challenge is the topic of this presentation. I will talk about an explicit MOT scheme developed for solving the TDVIE on scatterers with nonlinear material properties. The proposed scheme separately discretizes the TDVIE and the nonlinear constitutive relation between electric field intensity and flux density. The unknown field intensity and flux density are expanded using half and full Schaubert-Wilton-Glisson (SWG) basis functions in space and polynomial temporal interpolators in time. The resulting coupled system of the discretized TDVIE and constitutive relation is integrated in time using an explicit P E(CE) m scheme to yield the unknown expansion coefficients. Explicitness of time marching allows for straightforward incorporation of the nonlinearity as a function evaluation on the right hand side of the coupled system of equations. Consequently, the resulting MOT scheme does not call for a Newton-like nonlinear solver. Numerical examples, which demonstrate the applicability

  7. A Time Marching Scheme for Solving Volume Integral Equations on Nonlinear Scatterers

    KAUST Repository

    Bagci, Hakan

    2015-01-01

    Transient electromagnetic field interactions on inhomogeneous penetrable scatterers can be analyzed by solving time domain volume integral equations (TDVIEs). TDVIEs are oftentimes solved using marchingon-in-time (MOT) schemes. Unlike finite difference and finite element schemes, MOT-TDVIE solvers require discretization of only the scatterers, do not call for artificial absorbing boundary conditions, and are more robust to numerical phase dispersion. On the other hand, their computational cost is high, they suffer from late-time instabilities, and their implicit nature makes incorporation of nonlinear constitutive relations more difficult. Development of plane-wave time-domain (PWTD) and FFT-based schemes has significantly reduced the computational cost of the MOT-TDVIE solvers. Additionally, latetime instability problem has been alleviated for all practical purposes with the development of accurate integration schemes and specially designed temporal basis functions. Addressing the third challenge is the topic of this presentation. I will talk about an explicit MOT scheme developed for solving the TDVIE on scatterers with nonlinear material properties. The proposed scheme separately discretizes the TDVIE and the nonlinear constitutive relation between electric field intensity and flux density. The unknown field intensity and flux density are expanded using half and full Schaubert-Wilton-Glisson (SWG) basis functions in space and polynomial temporal interpolators in time. The resulting coupled system of the discretized TDVIE and constitutive relation is integrated in time using an explicit P E(CE) m scheme to yield the unknown expansion coefficients. Explicitness of time marching allows for straightforward incorporation of the nonlinearity as a function evaluation on the right hand side of the coupled system of equations. Consequently, the resulting MOT scheme does not call for a Newton-like nonlinear solver. Numerical examples, which demonstrate the applicability

  8. Synchronization of Coupled Different Chaotic FitzHugh-Nagumo Neurons with Unknown Parameters under Communication-Direction-Dependent Coupling

    Directory of Open Access Journals (Sweden)

    Muhammad Iqbal

    2014-01-01

    Full Text Available This paper investigates the chaotic behavior and synchronization of two different coupled chaotic FitzHugh-Nagumo (FHN neurons with unknown parameters under external electrical stimulation (EES. The coupled FHN neurons of different parameters admit unidirectional and bidirectional gap junctions in the medium between them. Dynamical properties, such as the increase in synchronization error as a consequence of the deviation of neuronal parameters for unlike neurons, the effect of difference in coupling strengths caused by the unidirectional gap junctions, and the impact of large time-delay due to separation of neurons, are studied in exploring the behavior of the coupled system. A novel integral-based nonlinear adaptive control scheme, to cope with the infeasibility of the recovery variable, for synchronization of two coupled delayed chaotic FHN neurons of different and unknown parameters under uncertain EES is derived. Further, to guarantee robust synchronization of different neurons against disturbances, the proposed control methodology is modified to achieve the uniformly ultimately bounded synchronization. The parametric estimation errors can be reduced by selecting suitable control parameters. The effectiveness of the proposed control scheme is illustrated via numerical simulations.

  9. The effect and contribution of wind generated rotation on outlet temperature and heat gain of LS-2 parabolic trough solar collector

    Directory of Open Access Journals (Sweden)

    Sadaghiyani Omid Karimi

    2013-01-01

    Full Text Available The Monte Carlo ray tracing method is applied and coupled with finite volume numerical methods to study effect of rotation on outlet temperature and heat gain of LS-2 parabolic trough concentrator (PTC. Based on effect of sunshape, curve of mirror and use of MCRT, heat flux distribution around of inner wall of evacuated tube is calculated. After calculation of heat flux, the geometry of LS-2 Luz collector is created and finite volume method is applied to simulate. The obtained results are compared with Dudley et al test results for irrotational cases to validate these numerical solving models. Consider that, for rotational models ,the solving method separately with K.S. Ball's results. In this work, according to the structure of mentioned collector, we use plug as a flow restriction. In the rotational case studies, the inner wall rotates with different angular speeds. We compare results of rotational collector with irrotational. Also for these two main states, the location of plug changed then outlet temperature and heat gain of collector are studied. The results show that rotation have positive role on heat transfer processing and the rotational plug in bottom half of tube have better effectual than upper half of tube. Also the contribution of rotation is calculated in the all of case studies. Working fluid of these study is one of the oil derivatives namely Syltherm-800. The power of wind can be used to rotate tube of collector.

  10. Study on the performance of the Particle Identification Detectors at LHCb after the LHC First Long Shutdown (LS1)

    CERN Document Server

    Fontana, Marianna

    2016-01-01

    During the First Long Shutdown (LS1), the LHCb experiment has introduced major modification in the data-processing procedure and modified part of the detector to deal with the increased energy and the increased heavy-hadron production cross-section. In this contribution we review the performance of the particle identification detectors at LHCb, Rich, Calorimeters, and Muon system, after the LS1

  11. PDF fit in the fixed-flavour-number scheme

    Energy Technology Data Exchange (ETDEWEB)

    Alekhin, S. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Institute for High Energy Physics, Moscow (Russian Federation); Bluemlein, J.; Moch, S. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2012-02-15

    We discuss the heavy-quark contribution to deep inelastic scattering in the scheme with n{sub f}=3;4;5 fixed flavors. Based on the recent ABM11 PDF analysis of world data for deep-inelastic scattering and fixed-target data for the Drell-Yan process with the running-mass definition for heavy quarks we show that fixed flavor number scheme is sufficient for describing the deep-inelastic-scattering data in the entire kinematic range. We compare with other PDF sets and comment on the implications for measuring the strong coupling constant {alpha}{sub s}(M{sub Z}).

  12. Diagnosis of leg osseous infection in diabetics: place of scintigraphy of the polynuclear hydrocarbons labelled by HMPAO-{sup 99m}Tc (HMPAO-LS); Diagnostic de l`infection osseuse du pied chez le diabetique: place de la scintigraphie aux polynucleaires marques a l`HMPAO-Tc 99m (HMPAO-LS)

    Energy Technology Data Exchange (ETDEWEB)

    Devillers, A.; Moisan, A.; Hennion, F.; Poirier, J.Y.; Bourguet, P. [CRLCC Eugene Marquis, Medecine Nucleaire, CHRU Endocrinologie, Rennes (France)

    1997-12-31

    In case of leg infection in diabetics it is difficult to differentiate between a chronic osteopathy, an infection of the soft tissues and an osteomyelitis (OM). We considered of interest to evaluate by a HMPAO-LS prospective study the diagnosis of osteitis in diabetic legs. Twenty seven diabetic (DID type 1 = 11, DNID type 2 = 16) patients (19 M and 8 F, average age 64 years), clinically suspected with a leg osteo-articular infection (malum perforans or cellulitis, uni- or bi-lateral, unique or multiple lesions) were included in the study. For all of them a standard radiographic examination centered on the legs, a (3 phases) osseous scintigraphy and a HMPAO-LS were achieved over 3 days. The HMPAO-LS was considered as in favour of a OM when there was an abnormal accumulation of granulocytes concordant with a hyper-fixation by osseous scintigraphy. In case of 37 retained lesions 20 OM were proved: - 8 sites, on radiological arguments and histological and/or microbiological criteria after osseous biopsy; - 8, by the radiological examination only; - 4, on biopsy arguments, only. Seventeen lesions were not OM, of which 7 were cellulitis. The sensitivity of the HMPAO-LS was 90% with a specificity of 94%. 8/20 OM had initial normal radiographs confirming the precocity of OM diagnosis by HMPAO-LS. Twelve HMPAO-LS were effected in OM evolutive surveillance. All of them became negative on the control initial site of the healing of OM. In conclusion, the HMPAO-LS appears to be an alternative to choose in the diagnosis and in the evolution surveillance of leg OM in diabetics, particularly when the healing of the perforans softs is incomplete and the question of the osteitis healing or sequel of an anti-biotherapy is posed

  13. SRIM Scheme: An Impression-Management Scheme for Privacy-Aware Photo-Sharing Users

    Directory of Open Access Journals (Sweden)

    Fenghua Li

    2018-02-01

    Full Text Available With the development of online social networks (OSNs and modern smartphones, sharing photos with friends has become one of the most popular social activities. Since people usually prefer to give others a positive impression, impression management during photo sharing is becoming increasingly important. However, most of the existing privacy-aware solutions have two main drawbacks: ① Users must decide manually whether to share each photo with others or not, in order to build the desired impression; and ② users run a high risk of leaking sensitive relational information in group photos during photo sharing, such as their position as part of a couple, or their sexual identity. In this paper, we propose a social relation impression-management (SRIM scheme to protect relational privacy and to automatically recommend an appropriate photo-sharing policy to users. To be more specific, we have designed a lightweight face-distance measurement that calculates the distances between users’ faces within group photos by relying on photo metadata and face-detection results. These distances are then transformed into relations using proxemics. Furthermore, we propose a relation impression evaluation algorithm to evaluate and manage relational impressions. We developed a prototype and employed 21 volunteers to verify the functionalities of the SRIM scheme. The evaluation results show the effectiveness and efficiency of our proposed scheme. Keywords: Impression management, Relational privacy, Photo sharing, Policy recommendation, Proxemics

  14. Dimensional renormalization and comparison of renormalization schemes in quantum electrodynamics

    International Nuclear Information System (INIS)

    Coquereaux, R.

    1979-02-01

    The method of dimensional renormalization as applied to quantum electrodynamics is discussed. A general method is given which allows one to compare the various quantities like coupling constants and masses that appear in different renormalization schemes

  15. Optimizing phonon space in the phonon-coupling model

    Science.gov (United States)

    Tselyaev, V.; Lyutorovich, N.; Speth, J.; Reinhard, P.-G.

    2017-08-01

    We present a new scheme to select the most relevant phonons in the phonon-coupling model, named here the time-blocking approximation (TBA). The new criterion, based on the phonon-nucleon coupling strengths rather than on B (E L ) values, is more selective and thus produces much smaller phonon spaces in the TBA. This is beneficial in two respects: first, it curbs the computational cost, and second, it reduces the danger of double counting in the expansion basis of the TBA. We use here the TBA in a form where the coupling strength is regularized to keep the given Hartree-Fock ground state stable. The scheme is implemented in a random-phase approximation and TBA code based on the Skyrme energy functional. We first explore carefully the cutoff dependence with the new criterion and can work out a natural (optimal) cutoff parameter. Then we use the freshly developed and tested scheme for a survey of giant resonances and low-lying collective states in six doubly magic nuclei looking also at the dependence of the results when varying the Skyrme parametrization.

  16. Fast-Solving Quasi-Optimal LS-S3VM Based on an Extended Candidate Set.

    Science.gov (United States)

    Ma, Yuefeng; Liang, Xun; Kwok, James T; Li, Jianping; Zhou, Xiaoping; Zhang, Haiyan

    2018-04-01

    The semisupervised least squares support vector machine (LS-S 3 VM) is an important enhancement of least squares support vector machines in semisupervised learning. Given that most data collected from the real world are without labels, semisupervised approaches are more applicable than standard supervised approaches. Although a few training methods for LS-S 3 VM exist, the problem of deriving the optimal decision hyperplane efficiently and effectually has not been solved. In this paper, a fully weighted model of LS-S 3 VM is proposed, and a simple integer programming (IP) model is introduced through an equivalent transformation to solve the model. Based on the distances between the unlabeled data and the decision hyperplane, a new indicator is designed to represent the possibility that the label of an unlabeled datum should be reversed in each iteration during training. Using the indicator, we construct an extended candidate set consisting of the indices of unlabeled data with high possibilities, which integrates more information from unlabeled data. Our algorithm is degenerated into a special scenario of the previous algorithm when the extended candidate set is reduced into a set with only one element. Two strategies are utilized to determine the descent directions based on the extended candidate set. Furthermore, we developed a novel method for locating a good starting point based on the properties of the equivalent IP model. Combined with the extended candidate set and the carefully computed starting point, a fast algorithm to solve LS-S 3 VM quasi-optimally is proposed. The choice of quasi-optimal solutions results in low computational cost and avoidance of overfitting. Experiments show that our algorithm equipped with the two designed strategies is more effective than other algorithms in at least one of the following three aspects: 1) computational complexity; 2) generalization ability; and 3) flexibility. However, our algorithm and other algorithms have

  17. Diagnosis of leg osseous infection in diabetics: place of scintigraphy of the polynuclear hydrocarbons labelled by HMPAO-99mTc (HMPAO-LS)

    International Nuclear Information System (INIS)

    Devillers, A.; Moisan, A.; Hennion, F.; Poirier, J.Y.; Bourguet, P.

    1997-01-01

    In case of leg infection in diabetics it is difficult to differentiate between a chronic osteopathy, an infection of the soft tissues and an osteomyelitis (OM). We considered of interest to evaluate by a HMPAO-LS prospective study the diagnosis of osteitis in diabetic legs. Twenty seven diabetic (DID type 1 = 11, DNID type 2 = 16) patients (19 M and 8 F, average age 64 years), clinically suspected with a leg osteo-articular infection (malum perforans or cellulitis, uni- or bi-lateral, unique or multiple lesions) were included in the study. For all of them a standard radiographic examination centered on the legs, a (3 phases) osseous scintigraphy and a HMPAO-LS were achieved over 3 days. The HMPAO-LS was considered as in favour of a OM when there was an abnormal accumulation of granulocytes concordant with a hyper-fixation by osseous scintigraphy. In case of 37 retained lesions 20 OM were proved: - 8 sites, on radiological arguments and histological and/or microbiological criteria after osseous biopsy; - 8, by the radiological examination only; - 4, on biopsy arguments, only. Seventeen lesions were not OM, of which 7 were cellulitis. The sensitivity of the HMPAO-LS was 90% with a specificity of 94%. 8/20 OM had initial normal radiographs confirming the precocity of OM diagnosis by HMPAO-LS. Twelve HMPAO-LS were effected in OM evolutive surveillance. All of them became negative on the control initial site of the healing of OM. In conclusion, the HMPAO-LS appears to be an alternative to choose in the diagnosis and in the evolution surveillance of leg OM in diabetics, particularly when the healing of the perforans softs is incomplete and the question of the osteitis healing or sequel of an anti-biotherapy is posed

  18. The Ne3LS Network, Québec's initiative to evaluate the impact and promote a responsible and sustainable development of nanotechnology

    Science.gov (United States)

    Endo, Charles-Anica; Emond, Claude; Battista, Renaldo; Parizeau, Marie-Hélène; Beaudry, Catherine

    2011-07-01

    The spectacular progress made by nanosciences and nanotechnologies elicits as much hope and fear. Consequently, a great number of research and training initiatives on the ethical, environmental, economic, legal and social issues regarding nanotechnology development (Ne3LS) are emerging worldwide. In Québec, Canada, a Task Force was mandated by NanoQuébec to conceive a Ne3LS research and training strategy to assess those issues. This Task Force brought together experts from universities, governments or industry working in nanosciences and nanotechnologies or in Ne3LS. Their resulting action plan, made public in November 2006, contained several recommendations, including the creation of a knowledge network (Ne3LS Network). In the following years, after consulting with numerous key players concerned with the possible impacts of nanosciences and nanotechnologies in Québec, the Ne3LS Network was launched in January 2010 in partnership with the Fonds québécois de la recherche sur la nature et les technologies, the Fonds québécois de la recherche sur la société et la culture and the Fonds de la recherche en santé du Québec, NanoQuébec, the Institut de recherche Robert-Sauvé en santé et en sécurité du travail as well as the University of Montreal. Its objectives are to 1) Foster the development of Ne3LS research activities (grants and fellowships); 2) Spearhead the Canadian and international Ne3LS network; 3) Take part in the training of researchers and experts; 4) Encourage the creation of interactive tools for the general public; 5) Facilitate collaboration between decision-makers and experts; 6) Involve the scientific community through a host of activities (symposium, conferences, thematic events); 7) Build multidisciplinary research teams to evaluate the impact of nanotechnology.

  19. Iteration scheme for implicit calculations of kinetic and equilibrium chemical reactions in fluid dynamics

    International Nuclear Information System (INIS)

    Ramshaw, J.D.; Chang, C.H.

    1995-01-01

    An iteration scheme for the implicit treatment of equilibrium chemical reactions in partial equilibrium flow has previously been described. Here we generalize this scheme to kinetic reactions as well as equilibrium reactions. This extends the applicability of the scheme to problems with kinetic reactions that are fast in regions of the flow field but slow in others. The resulting scheme thereby provides a single unified framework for the implicit treatment of an arbitrary number of coupled equilibrium and kinetic reactions in chemically reacting fluid flow. 10 refs., 2 figs

  20. Additive operator-difference schemes splitting schemes

    CERN Document Server

    Vabishchevich, Petr N

    2013-01-01

    Applied mathematical modeling isconcerned with solving unsteady problems. This bookshows how toconstruct additive difference schemes to solve approximately unsteady multi-dimensional problems for PDEs. Two classes of schemes are highlighted: methods of splitting with respect to spatial variables (alternating direction methods) and schemes of splitting into physical processes. Also regionally additive schemes (domain decomposition methods)and unconditionally stable additive schemes of multi-component splitting are considered for evolutionary equations of first and second order as well as for sy

  1. The same number of optimized parameters scheme for determining intermolecular interaction energies

    DEFF Research Database (Denmark)

    Kristensen, Kasper; Ettenhuber, Patrick; Eriksen, Janus Juul

    2015-01-01

    We propose the Same Number Of Optimized Parameters (SNOOP) scheme as an alternative to the counterpoise method for treating basis set superposition errors in calculations of intermolecular interaction energies. The key point of the SNOOP scheme is to enforce that the number of optimized wave...... as numerically. Numerical results for second-order Møller-Plesset perturbation theory (MP2) and coupled-cluster with single, double, and approximate triple excitations (CCSD(T)) show that the SNOOP scheme in general outperforms the uncorrected and counterpoise approaches. Furthermore, we show that SNOOP...

  2. Semantic Web applications and tools for the life sciences: SWAT4LS 2010.

    Science.gov (United States)

    Burger, Albert; Paschke, Adrian; Romano, Paolo; Marshall, M Scott; Splendiani, Andrea

    2012-01-25

    As Semantic Web technologies mature and new releases of key elements, such as SPARQL 1.1 and OWL 2.0, become available, the Life Sciences continue to push the boundaries of these technologies with ever more sophisticated tools and applications. Unsurprisingly, therefore, interest in the SWAT4LS (Semantic Web Applications and Tools for the Life Sciences) activities have remained high, as was evident during the third international SWAT4LS workshop held in Berlin in December 2010. Contributors to this workshop were invited to submit extended versions of their papers, the best of which are now made available in the special supplement of BMC Bioinformatics. The papers reflect the wide range of work in this area, covering the storage and querying of Life Sciences data in RDF triple stores, tools for the development of biomedical ontologies and the semantics-based integration of Life Sciences as well as clinicial data.

  3. Double beta decay in the generalized seniority scheme

    International Nuclear Information System (INIS)

    Pittel, S.; Engel, J.; Vogel, P.; Ji Xiangdong

    1990-01-01

    A generalized-seniority truncation scheme is used in shell-model calculations of double beta decay matrix elements. Calculations are carried out for 78 Ge, 82 Se and 128,130 Te. Matrix elements calculated for the two-neutrino decay mode are small compared to weak-coupling shell-model calculations and support the suppression mechanism first observed in the quasi-particle random phase approximation. Matrix elements for the neutrinoless mode are similar to those of the weak-coupling shell model, suggesting that these matrix elements can be pinned down fairly accurately. (orig.)

  4. The large-scale blast score ratio (LS-BSR pipeline: a method to rapidly compare genetic content between bacterial genomes

    Directory of Open Access Journals (Sweden)

    Jason W. Sahl

    2014-04-01

    Full Text Available Background. As whole genome sequence data from bacterial isolates becomes cheaper to generate, computational methods are needed to correlate sequence data with biological observations. Here we present the large-scale BLAST score ratio (LS-BSR pipeline, which rapidly compares the genetic content of hundreds to thousands of bacterial genomes, and returns a matrix that describes the relatedness of all coding sequences (CDSs in all genomes surveyed. This matrix can be easily parsed in order to identify genetic relationships between bacterial genomes. Although pipelines have been published that group peptides by sequence similarity, no other software performs the rapid, large-scale, full-genome comparative analyses carried out by LS-BSR.Results. To demonstrate the utility of the method, the LS-BSR pipeline was tested on 96 Escherichia coli and Shigella genomes; the pipeline ran in 163 min using 16 processors, which is a greater than 7-fold speedup compared to using a single processor. The BSR values for each CDS, which indicate a relative level of relatedness, were then mapped to each genome on an independent core genome single nucleotide polymorphism (SNP based phylogeny. Comparisons were then used to identify clade specific CDS markers and validate the LS-BSR pipeline based on molecular markers that delineate between classical E. coli pathogenic variant (pathovar designations. Scalability tests demonstrated that the LS-BSR pipeline can process 1,000 E. coli genomes in 27–57 h, depending upon the alignment method, using 16 processors.Conclusions. LS-BSR is an open-source, parallel implementation of the BSR algorithm, enabling rapid comparison of the genetic content of large numbers of genomes. The results of the pipeline can be used to identify specific markers between user-defined phylogenetic groups, and to identify the loss and/or acquisition of genetic information between bacterial isolates. Taxa-specific genetic markers can then be translated

  5. The LS-STAG immersed boundary/cut-cell method for non-Newtonian flows in 3D extruded geometries

    Science.gov (United States)

    Nikfarjam, F.; Cheny, Y.; Botella, O.

    2018-05-01

    The LS-STAG method is an immersed boundary/cut-cell method for viscous incompressible flows based on the staggered MAC arrangement for Cartesian grids, where the irregular boundary is sharply represented by its level-set function, results in a significant gain in computer resources (wall time, memory usage) compared to commercial body-fitted CFD codes. The 2D version of LS-STAG method is now well-established (Cheny and Botella, 2010), and this paper presents its extension to 3D geometries with translational symmetry in the z direction (hereinafter called 3D extruded configurations). This intermediate step towards the fully 3D implementation can be applied to a wide variety of canonical flows and will be regarded as the keystone for the full 3D solver, since both discretization and implementation issues on distributed memory machines are tackled at this stage of development. The LS-STAG method is then applied to various Newtonian and non-Newtonian flows in 3D extruded geometries (axisymmetric pipe, circular cylinder, duct with an abrupt expansion) for which benchmark results and experimental data are available. The purpose of these investigations are (a) to investigate the formal order of accuracy of the LS-STAG method, (b) to assess the versatility of method for flow applications at various regimes (Newtonian and shear-thinning fluids, steady and unsteady laminar to turbulent flows) (c) to compare its performance with well-established numerical methods (body-fitted and immersed boundary methods).

  6. A modified chaos-based communication scheme using Hamiltonian forms and observer

    International Nuclear Information System (INIS)

    Lopez-Mancilla, D; Cruz-Hernandez, C; Posadas-Castillo, C

    2005-01-01

    In this work, a modified chaos-based communication scheme is presented. In particular, we use the modified scheme proposed by Lopez-Mancilla and Cruz-Hernandez (2005), that improves the basic scheme for chaotic masking using a single transmission channel proposed by Cuomo and coworkers (1993). It is extended for a special class of Generalized Hamiltonian systems. Substantial differences that significantly affect the reception quality of the sent message, with or without considering noise effect in the transmission channel are given. We use two Hamiltonian Lorenz systems unidirectionally coupled, the first like a master/transmitter system and the other like a slave/receiver system in order to illustrate with numerical simulations the effectiveness of the modified scheme, using chaos synchronization with Hamiltonian forms and observer

  7. A modified chaos-based communication scheme using Hamiltonian forms and observer

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Mancilla, D [Engineering Faculty, Baja California Autonomous University (UABC), Km. 103, Carretera Tijuana-Ensenada, 22860, Ensenada, B.C. (Mexico); Cruz-Hernandez, C [Telematics Direction, Scientific Research and Advanced Studies of Ensenada (CICESE), Km. 107 Carretera Tijuana-Ensenada, 22860 Ensenada, B.C. (Mexico); Posadas-Castillo, C [Engineering Faculty, Baja California Autonomous University (UABC), Km. 103, Carretera Tijuana-Ensenada, 22860, Ensenada, B.C. (Mexico); Faculty of Engineering Mechanic and Electrical (FIME), Nuevo Leon Autonomous University (UANL), Pedro de alba s/n Cd. Universitaria San Nicolas de los Garza N.L. (Mexico)

    2005-01-01

    In this work, a modified chaos-based communication scheme is presented. In particular, we use the modified scheme proposed by Lopez-Mancilla and Cruz-Hernandez (2005), that improves the basic scheme for chaotic masking using a single transmission channel proposed by Cuomo and coworkers (1993). It is extended for a special class of Generalized Hamiltonian systems. Substantial differences that significantly affect the reception quality of the sent message, with or without considering noise effect in the transmission channel are given. We use two Hamiltonian Lorenz systems unidirectionally coupled, the first like a master/transmitter system and the other like a slave/receiver system in order to illustrate with numerical simulations the effectiveness of the modified scheme, using chaos synchronization with Hamiltonian forms and observer.

  8. Development of strongly coupled FSI technology involving thin walled structures

    CSIR Research Space (South Africa)

    Suliman, Ridhwaan

    2011-01-01

    Full Text Available A strongly coupled finite volume-finite element fluid-structure interaction (FSI) scheme is developed. Both an edge-based finite volume and Galerkin finite element scheme are implemented and evaluated for modelling the mechanics of solids...

  9. Comparison of three ice cloud optical schemes in climate simulations with community atmospheric model version 5

    Science.gov (United States)

    Zhao, Wenjie; Peng, Yiran; Wang, Bin; Yi, Bingqi; Lin, Yanluan; Li, Jiangnan

    2018-05-01

    A newly implemented Baum-Yang scheme for simulating ice cloud optical properties is compared with existing schemes (Mitchell and Fu schemes) in a standalone radiative transfer model and in the global climate model (GCM) Community Atmospheric Model Version 5 (CAM5). This study systematically analyzes the effect of different ice cloud optical schemes on global radiation and climate by a series of simulations with a simplified standalone radiative transfer model, atmospheric GCM CAM5, and a comprehensive coupled climate model. Results from the standalone radiative model show that Baum-Yang scheme yields generally weaker effects of ice cloud on temperature profiles both in shortwave and longwave spectrum. CAM5 simulations indicate that Baum-Yang scheme in place of Mitchell/Fu scheme tends to cool the upper atmosphere and strengthen the thermodynamic instability in low- and mid-latitudes, which could intensify the Hadley circulation and dehydrate the subtropics. When CAM5 is coupled with a slab ocean model to include simplified air-sea interaction, reduced downward longwave flux to surface in Baum-Yang scheme mitigates ice-albedo feedback in the Arctic as well as water vapor and cloud feedbacks in low- and mid-latitudes, resulting in an overall temperature decrease by 3.0/1.4 °C globally compared with Mitchell/Fu schemes. Radiative effect and climate feedback of the three ice cloud optical schemes documented in this study can be referred for future improvements on ice cloud simulation in CAM5.

  10. The Harmonically Coupled 2-Beam FEL

    CERN Document Server

    McNeil, Brian W J

    2004-01-01

    A 1-D model of a 2-beam Free Electron Laser amplifier is presented. The two co-propagating electron beams have different energies, chosen so that the fundamental resonant FEL interaction of the higher energy beam is at an harmonic of the lower energy beam. In this way, a coupling between the FEL interactions of the two beams occurs via the harmonic components of the electron bunching and radiation emission of the lower energy interaction. Such resonantly coupled FEL interactions may offer potential benefits over existing single beam FEL schemes. A simple example is presented where the lower energy FEL interaction only is seeded with radiation at its fundamental resonant wavelength. It is predicted that the coherence properties of this seed field are transfered via the resonantly coupled FEL interaction to the un-seeded higher energy FEL interaction, thereby improving its coherence properties over that of a SASE interaction alone. This method may offer an alternative seeding scheme for FELs operating in the XU...

  11. Support vector machine regression (LS-SVM)--an alternative to artificial neural networks (ANNs) for the analysis of quantum chemistry data?

    Science.gov (United States)

    Balabin, Roman M; Lomakina, Ekaterina I

    2011-06-28

    A multilayer feed-forward artificial neural network (MLP-ANN) with a single, hidden layer that contains a finite number of neurons can be regarded as a universal non-linear approximator. Today, the ANN method and linear regression (MLR) model are widely used for quantum chemistry (QC) data analysis (e.g., thermochemistry) to improve their accuracy (e.g., Gaussian G2-G4, B3LYP/B3-LYP, X1, or W1 theoretical methods). In this study, an alternative approach based on support vector machines (SVMs) is used, the least squares support vector machine (LS-SVM) regression. It has been applied to ab initio (first principle) and density functional theory (DFT) quantum chemistry data. So, QC + SVM methodology is an alternative to QC + ANN one. The task of the study was to estimate the Møller-Plesset (MPn) or DFT (B3LYP, BLYP, BMK) energies calculated with large basis sets (e.g., 6-311G(3df,3pd)) using smaller ones (6-311G, 6-311G*, 6-311G**) plus molecular descriptors. A molecular set (BRM-208) containing a total of 208 organic molecules was constructed and used for the LS-SVM training, cross-validation, and testing. MP2, MP3, MP4(DQ), MP4(SDQ), and MP4/MP4(SDTQ) ab initio methods were tested. Hartree-Fock (HF/SCF) results were also reported for comparison. Furthermore, constitutional (CD: total number of atoms and mole fractions of different atoms) and quantum-chemical (QD: HOMO-LUMO gap, dipole moment, average polarizability, and quadrupole moment) molecular descriptors were used for the building of the LS-SVM calibration model. Prediction accuracies (MADs) of 1.62 ± 0.51 and 0.85 ± 0.24 kcal mol(-1) (1 kcal mol(-1) = 4.184 kJ mol(-1)) were reached for SVM-based approximations of ab initio and DFT energies, respectively. The LS-SVM model was more accurate than the MLR model. A comparison with the artificial neural network approach shows that the accuracy of the LS-SVM method is similar to the accuracy of ANN. The extrapolation and interpolation results show that LS-SVM is

  12. Coupling and Vertical Dispersion Correction in the SPS

    CERN Document Server

    Aiba, M; Franchi, A; Tomas, R; Vanbavinckhove, G

    2010-01-01

    Consolidation of the coupling correction scheme in the LHC is challenged by a missing skew quadrupole family in Sector 3-4 at the start-up in 2009-2010. Simultaneous coupling and vertical dispersion correction using vertical orbit bumps at the sextupoles, was studied by analyzing turn-byturn data. This scheme was tested in the CERN SPS where the optical structure of arc cells is quite similar to the LHC. In the SPS, horizontal and vertical beam positions are measured separately with single plane BPMs, thus a technique to construct ”pseudo double plane BPM” is also discussed.

  13. Novel Electro-Optical Coupling Technique for Magnetic Resonance-Compatible Positron Emission Tomography Detectors

    Directory of Open Access Journals (Sweden)

    Peter D. Olcott

    2009-03-01

    Full Text Available A new magnetic resonance imaging (MRI-compatible positron emission tomography (PET detector design is being developed that uses electro-optical coupling to bring the amplitude and arrival time information of high-speed PET detector scintillation pulses out of an MRI system. The electro-optical coupling technology consists of a magnetically insensitive photodetector output signal connected to a nonmagnetic vertical cavity surface emitting laser (VCSEL diode that is coupled to a multimode optical fiber. This scheme essentially acts as an optical wire with no influence on the MRI system. To test the feasibility of this approach, a lutetium-yttrium oxyorthosilicate crystal coupled to a single pixel of a solid-state photomultiplier array was placed in coincidence with a lutetium oxyorthosilicate crystal coupled to a fast photomultiplier tube with both the new nonmagnetic VCSEL coupling and the standard coaxial cable signal transmission scheme. No significant change was observed in 511 keV photopeak energy resolution and coincidence time resolution. This electro-optical coupling technology enables an MRI-compatible PET block detector to have a reduced electromagnetic footprint compared with the signal transmission schemes deployed in the current MRI/PET designs.

  14. Novel electro-optical coupling technique for magnetic resonance-compatible positron emission tomography detectors.

    Science.gov (United States)

    Olcott, Peter D; Peng, Hao; Levin, Craig S

    2009-01-01

    A new magnetic resonance imaging (MRI)-compatible positron emission tomography (PET) detector design is being developed that uses electro-optical coupling to bring the amplitude and arrival time information of high-speed PET detector scintillation pulses out of an MRI system. The electro-optical coupling technology consists of a magnetically insensitive photodetector output signal connected to a nonmagnetic vertical cavity surface emitting laser (VCSEL) diode that is coupled to a multimode optical fiber. This scheme essentially acts as an optical wire with no influence on the MRI system. To test the feasibility of this approach, a lutetium-yttrium oxyorthosilicate crystal coupled to a single pixel of a solid-state photomultiplier array was placed in coincidence with a lutetium oxyorthosilicate crystal coupled to a fast photomultiplier tube with both the new nonmagnetic VCSEL coupling and the standard coaxial cable signal transmission scheme. No significant change was observed in 511 keV photopeak energy resolution and coincidence time resolution. This electro-optical coupling technology enables an MRI-compatible PET block detector to have a reduced electromagnetic footprint compared with the signal transmission schemes deployed in the current MRI/PET designs.

  15. Charge-conserving FEM-PIC schemes on general grids

    International Nuclear Information System (INIS)

    Campos Pinto, M.; Jund, S.; Salmon, S.; Sonnendruecker, E.

    2014-01-01

    Particle-In-Cell (PIC) solvers are a major tool for the understanding of the complex behavior of a plasma or a particle beam in many situations. An important issue for electromagnetic PIC solvers, where the fields are computed using Maxwell's equations, is the problem of discrete charge conservation. In this article, we aim at proposing a general mathematical formulation for charge-conserving finite-element Maxwell solvers coupled with particle schemes. In particular, we identify the finite-element continuity equations that must be satisfied by the discrete current sources for several classes of time-domain Vlasov-Maxwell simulations to preserve the Gauss law at each time step, and propose a generic algorithm for computing such consistent sources. Since our results cover a wide range of schemes (namely curl-conforming finite element methods of arbitrary degree, general meshes in two or three dimensions, several classes of time discretization schemes, particles with arbitrary shape factors and piecewise polynomial trajectories of arbitrary degree), we believe that they provide a useful roadmap in the design of high-order charge-conserving FEM-PIC numerical schemes. (authors)

  16. Mixed synchronization in chaotic oscillators using scalar coupling

    Energy Technology Data Exchange (ETDEWEB)

    Bhowmick, Sourav K.; Hens, Chittaranjan [CSIR – Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032 (India); Ghosh, Dibakar, E-mail: drghosh_math@yahoo.co.in [Department of Mathematics, University of Kalyani, West Bengal 741235 (India); Dana, Syamal K. [CSIR – Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032 (India)

    2012-07-23

    We report experimental evidence of mixed synchronization in two unidirectionally coupled chaotic oscillators using a scalar coupling. In this synchronization regime, some of the state variables may be in complete synchronization while others may be in anti-synchronization state. We extended the theory by using an adaptive controller with an updating law based on Lyapunov function stability to include parameter fluctuation. Using the scheme, we implemented a cryptographic encoding for digital signal through parameter modulation. -- Highlights: ► We provided experimental evidence of the mixed synchronization scheme while other methods are mostly theoretical nature. ► We numerically studied adaptive mixed synchronization when the parameters are not completely known using scalar coupling. ► We proposed a secure communication system where three digital messages are transmitted using parameter modulation.

  17. Analysis of the F. Calogero Type Projection-Algebraic Scheme for Differential Operator Equations

    International Nuclear Information System (INIS)

    Lustyk, Miroslaw; Bogolubov, Nikolai N. Jr.; Blackmore, Denis; Prykarpatsky, Anatoliy K.

    2010-12-01

    The existence, convergence, realizability and stability of solutions of differential operator equations obtained via a novel projection-algebraic scheme are analyzed in detail. This analysis is based upon classical discrete approximation techniques coupled with a recent generalization of the Leray-Schauder fixed point theorem. An example is included to illustrate the efficacy of the projection scheme and analysis strategy. (author)

  18. Multistage Coupling of Laser-Wakefield Accelerators with Curved Plasma Channels

    Science.gov (United States)

    Luo, J.; Chen, M.; Wu, W. Y.; Weng, S. M.; Sheng, Z. M.; Schroeder, C. B.; Jaroszynski, D. A.; Esarey, E.; Leemans, W. P.; Mori, W. B.; Zhang, J.

    2018-04-01

    Multistage coupling of laser-wakefield accelerators is essential to overcome laser energy depletion for high-energy applications such as TeV-level electron-positron colliders. Current staging schemes feed subsequent laser pulses into stages using plasma mirrors while controlling electron beam focusing with plasma lenses. Here a more compact and efficient scheme is proposed to realize the simultaneous coupling of the electron beam and the laser pulse into a second stage. A partly curved channel, integrating a straight acceleration stage with a curved transition segment, is used to guide a fresh laser pulse into a subsequent straight channel, while the electrons continue straight. This scheme benefits from a shorter coupling distance and continuous guiding of the electrons in plasma while suppressing transverse beam dispersion. Particle-in-cell simulations demonstrate that the electron beam from a previous stage can be efficiently injected into a subsequent stage for further acceleration while maintaining high capture efficiency, stability, and beam quality.

  19. Measuring Trace Gas Emission from Multi-Distributed Sources Using Vertical Radial Plume Mapping (VRPM and Backward Lagrangian Stochastic (bLS Techniques

    Directory of Open Access Journals (Sweden)

    Thomas K. Flesch

    2011-09-01

    Full Text Available Two micrometeorological techniques for measuring trace gas emission rates from distributed area sources were evaluated using a variety of synthetic area sources. The vertical radial plume mapping (VRPM and the backward Lagrangian stochastic (bLS techniques with an open-path optical spectroscopic sensor were evaluated for relative accuracy for multiple emission-source and sensor configurations. The relative accuracy was calculated by dividing the measured emission rate by the actual emission rate; thus, a relative accuracy of 1.0 represents a perfect measure. For a single area emission source, the VRPM technique yielded a somewhat high relative accuracy of 1.38 ± 0.28. The bLS technique resulted in a relative accuracy close to unity, 0.98 ± 0.24. Relative accuracies for dual source emissions for the VRPM and bLS techniques were somewhat similar to single source emissions, 1.23 ± 0.17 and 0.94 ± 0.24, respectively. When the bLS technique was used with vertical point concentrations, the relative accuracy was unacceptably low,

  20. A light weight secure image encryption scheme based on chaos & DNA computing

    Directory of Open Access Journals (Sweden)

    Bhaskar Mondal

    2017-10-01

    Full Text Available This paper proposed a new light weight secure cryptographic scheme for secure image communication. In this scheme the plain image is permuted first using a sequence of pseudo random number (PRN and encrypted by DeoxyriboNucleic Acid (DNA computation. Two PRN sequences are generated by a Pseudo Random Number Generator (PRNG based on cross coupled chaotic logistic map using two sets of keys. The first PRN sequence is used for permuting the plain image whereas the second PRN sequence is used for generating random DNA sequence. The number of rounds of permutation and encryption may be variable to increase security. The scheme is proposed for gray label images but the scheme may be extended for color images and text data. Simulation results exhibit that the proposed scheme can defy any kind of attack.

  1. LS1 Report: short-circuit tests

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    As the LS1 draws to an end, teams move from installation projects to a phase of intense testing. Among these are the so-called 'short-circuit tests'. Currently under way at Point 7, these tests verify the cables, the interlocks, the energy extraction systems, the power converters that provide current to the superconducting magnets and the cooling system.   Thermal camera images taken during tests at point 4 (IP4). Before putting beam into the LHC, all of the machine's hardware components need to be put to the test. Out of these, the most complicated are the superconducting circuits, which have a myriad of different failure modes with interlock and control systems. While these will be tested at cold - during powering tests to be done in August - work can still be done beforehand. "While the circuits in the magnets themselves cannot be tested at warm, what we can do is verify the power converter and the circuits right up to the place the cables go into the magn...

  2. LS1 Report: Summer cool down

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    As the final LS1 activities are carried out in the machine, teams have been cooling down the accelerator sector by sector in preparation for beams.   The third sector of the LHC to be cooled down - sector 1-2 - has seen the process begin this week. During the cool-down phase, survey teams are measuring and smoothing (or realigning) the magnets at cold. By the end of August, five sectors of the machine will be in the process of cooling down, with one (sector 6-7) at cold. The LHC Access Safety System (LASS) is now being commissioned, and will be validated during the DSO tests at the beginning of October. As teams consolidate the modifications made to LASS during the shutdown, many points were closed for testing purposes. The CSCM (copper stabiliser continuity measurement) tests have been completed in the first sector (6-7) and no defect has been found. These results will be presented to the LHC Machine Committee next week. CSCM tests will start in the second sector in mid-August. Following many...

  3. LS1 Report: onwards and upwards

    CERN Multimedia

    Katarina Anthony

    2013-01-01

    For the first time since 2008, engineers have taken most of the LHC’s electromagnetic circuits up to the current needed for magnets to guide beams around the machine at the design energy of 7 TeV. This first phase of intensive tests has been instrumental for the planning of upcoming machine interventions.   All of the circuits in Sector 67 were powered to a 7 TeV equivalent current, with the main circuits (to be consolidated during LS1) powered at 4 TeV. Around 1700 magnet circuits are needed to circulate beams in the LHC. Come 2015, each and every one of these circuits will have to be able to accept their 7 TeV equivalent current. For the LHC’s 24 main dipole and quadrupole circuits, this will mean the consolidation of all their interconnections. But what about the rest of the LHC’s circuits that had been mostly operating at around 60% of the nominal value? How will they handle the ramp-up to design energy? Those questions were asked and answered during the rec...

  4. LS1 Report: LHCb's early Christmas

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Accelerator chain up and running... CCC Operators back at their desks... all telltale signs of the start of Run 2! For the experiments, that means there are just a few short weeks left for them to prepare for beams. Over at LHCb, teams have kept ahead of the curve by focusing on new installations and improvements.   A delicate task: re-connecting the beam pipe in LHCb. From the primary detector services to the DAQ system to the high level trigger, November's injector test beams saw their way through a well-prepared LHCb experiment. “We set the transfer line tests as our deadline for the restart - the entire experiment had to be at nominal position and conditions,” says Eric Thomas, LHCb deputy Technical Coordinator and LHCb LS1 Project Coordinator. “Achieving this was a major milestone for the collaboration. If beam were to come tomorrow, we would be ready.” The injector tests gave the LHCb team a chance to synchronise their detectors, and to al...

  5. The new electricity of France PWR: calculation scheme of neutron leakages from the reactor cavity

    International Nuclear Information System (INIS)

    Vergnaud, T.; Bourdet, L.; Nimal, J.C.; Brandicourt, G.; Champion, G.

    1987-04-01

    A new calculation scheme is adapted to evaluate neutron fluxes in the reactor cavity and the containment of next french PWR. In this scheme a large part is given to Monte Carlo method, coupled with SN-method, in order to take into account multiple neutron diffusions and the complexity of the reactor geometry

  6. Photoionisation of O6+ below the n=3 threshold of the reduced ion

    International Nuclear Information System (INIS)

    Faye, N.A.B.; Wague, A.

    1994-01-01

    Near the n=3 threshold of residual ion O 7+ , the resonant photoionization of the multicharged ion O 6+ is considered by calculating the excitation energies, associated wave-functions, partial and total widths of the 1 P (-) and 3 P (-) autoionizing states. These calculations are made in the diagonalization approximation in the LS coupling scheme. The results are compared with the available theoretical results obtained by authors using other theoretical approaches. (author). 16 refs, 5 tabs

  7. Lymphoscintigraphy (LS) in infants and children: techniques and scintigraphic patterns

    International Nuclear Information System (INIS)

    Somerville, J.; Parsons, G.; Howman-Giles, R.; Lewis, G.; Uren, R.; Mansberg, R.

    1999-01-01

    Full text: Radionuclide imaging of the lymphatic system with intradermal injection of radiopharmaceutical is a rapid, safe and simple technique for the evaluation of lymphatic abnormalities in infants and children. 99 Tc m -antimony sulphide colloid is the agent of choice. The radiopharmaceutical (dose 5 mBq in 0.1 ml) is injected intradermally into both limbs being investigated. Emla cream is useful to reduce the initial discomfort of the injection. Imaging is performed immediately for approximately 30-60 min to assess the flow rate and lymph channels to the draining node fields. Further imaging at 2 and 4 h may be necessary. Normal LS in the lower limbs shows the tracer to pass into lymphatics almost immediately and channels are usually visualized within 5 min. In the lower limbs, symmetrical lymph flow to nodes are seen in the groin, iliac and paravertebral region with activity later seen in the liver. In 31 patients studied over the last 3 years, 17 studies were normal and 14 were abnormal: Klippel-Trenaunay-Weber syndrome (n = 4) with delayed flow and dermal backflow; congenital lymph/vascular malformations (n = 6) with various delayed flow patterns and focal accumulations; congenital lymphoedema (n 3) and pulmonary lymphangiectasia (n = 1). Aplasia and hypoplasia of lymph systems are readily identified. In conclusion, LS is a valuable diagnostic technique to assess lymph flow and diagnose lymphatic malformations and the causes of lymphoedema in children

  8. Microelectrode voltammetry of multi-electron transfers complicated by coupled chemical equilibria: a general theory for the extended square scheme.

    Science.gov (United States)

    Laborda, Eduardo; Gómez-Gil, José María; Molina, Angela

    2017-06-28

    A very general and simple theoretical solution is presented for the current-potential-time response of reversible multi-electron transfer processes complicated by homogeneous chemical equilibria (the so-called extended square scheme). The expressions presented here are applicable regardless of the number of electrons transferred and coupled chemical processes, and they are particularized for a wide variety of microelectrode geometries. The voltammetric response of very different systems presenting multi-electron transfers is considered for the most widely-used techniques (namely, cyclic voltammetry, square wave voltammetry, differential pulse voltammetry and steady state voltammetry), studying the influence of the microelectrode geometry and the number and thermodynamics of the (electro)chemical steps. Most appropriate techniques and procedures for the determination of the 'interaction' between successive transfers are discussed. Special attention is paid to those situations where homogeneous chemical processes, such as protonation, complexation or ion association, affect the electrochemical behaviour of the system by different stabilization of the oxidation states.

  9. The linearly scaling 3D fragment method for large scale electronic structure calculations

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Zhengji [National Energy Research Scientific Computing Center (NERSC) (United States); Meza, Juan; Shan Hongzhang; Strohmaier, Erich; Bailey, David; Wang Linwang [Computational Research Division, Lawrence Berkeley National Laboratory (United States); Lee, Byounghak, E-mail: ZZhao@lbl.go [Physics Department, Texas State University (United States)

    2009-07-01

    The linearly scaling three-dimensional fragment (LS3DF) method is an O(N) ab initio electronic structure method for large-scale nano material simulations. It is a divide-and-conquer approach with a novel patching scheme that effectively cancels out the artificial boundary effects, which exist in all divide-and-conquer schemes. This method has made ab initio simulations of thousand-atom nanosystems feasible in a couple of hours, while retaining essentially the same accuracy as the direct calculation methods. The LS3DF method won the 2008 ACM Gordon Bell Prize for algorithm innovation. Our code has reached 442 Tflop/s running on 147,456 processors on the Cray XT5 (Jaguar) at OLCF, and has been run on 163,840 processors on the Blue Gene/P (Intrepid) at ALCF, and has been applied to a system containing 36,000 atoms. In this paper, we will present the recent parallel performance results of this code, and will apply the method to asymmetric CdSe/CdS core/shell nanorods, which have potential applications in electronic devices and solar cells.

  10. The little-studied cluster Berkeley 90. I. LS III +46 11: a very massive O3.5 If* + O3.5 If* binary

    Science.gov (United States)

    Maíz Apellániz, J.; Negueruela, I.; Barbá, R. H.; Walborn, N. R.; Pellerin, A.; Simón-Díaz, S.; Sota, A.; Marco, A.; Alonso-Santiago, J.; Sanchez Bermudez, J.; Gamen, R. C.; Lorenzo, J.

    2015-07-01

    Context. It appears that most (if not all) massive stars are born in multiple systems. At the same time, the most massive binaries are hard to find owing to their low numbers throughout the Galaxy and the implied large distances and extinctions. Aims: We want to study LS III +46 11, identified in this paper as a very massive binary; another nearby massive system, LS III +46 12; and the surrounding stellar cluster, Berkeley 90. Methods: Most of the data used in this paper are multi-epoch high S/N optical spectra, although we also use Lucky Imaging and archival photometry. The spectra are reduced with dedicated pipelines and processed with our own software, such as a spectroscopic-orbit code, CHORIZOS, and MGB. Results: LS III +46 11 is identified as a new very early O-type spectroscopic binary [O3.5 If* + O3.5 If*] and LS III +46 12 as another early O-type system [O4.5 V((f))]. We measure a 97.2-day period for LS III +46 11 and derive minimum masses of 38.80 ± 0.83 M⊙ and 35.60 ± 0.77 M⊙ for its two stars. We measure the extinction to both stars, estimate the distance, search for optical companions, and study the surrounding cluster. In doing so, a variable extinction is found as well as discrepant results for the distance. We discuss possible explanations and suggest that LS III +46 12 may be a hidden binary system where the companion is currently undetected.

  11. Generalized N-coupled maps with invariant measure in Bose ...

    Indian Academy of Sciences (India)

    Algebraic properties of the Bose-Mesner algebra with an associated scheme with definite spectrum has been used in order to study the stability of the coupled map lattice. Associated schemes play a key role and may lead to analytical methods in studying the stability of the dynamical systems. The relation between the ...

  12. Topology Detection for Output-Coupling Weighted Complex Dynamical Networks with Coupling and Transmission Delays

    Directory of Open Access Journals (Sweden)

    Xinwei Wang

    2017-01-01

    Full Text Available Topology detection for output-coupling weighted complex dynamical networks with two types of time delays is investigated in this paper. Different from existing literatures, coupling delay and transmission delay are simultaneously taken into account in the output-coupling network. Based on the idea of the state observer, we build the drive-response system and apply LaSalle’s invariance principle to the error dynamical system of the drive-response system. Several convergent criteria are deduced in the form of algebraic inequalities. Some numerical simulations for the complex dynamical network, with node dynamics being chaotic, are given to verify the effectiveness of the proposed scheme.

  13. Characterization of a fiber-taper charge-coupled device system for plastic scintillation dosimetry and comparison with the traditional lens system

    International Nuclear Information System (INIS)

    Gagnon, Louis-Philippe; Beddar, Sam; Beaulieu, Luc

    2015-01-01

    Purpose: To compare the signal-to-noise ratio (SNR), dose sensitivity and stability, and reproducibility of a lens-less charge-coupled device (CCD) photon-counting system with those of a traditional CCD + lens photon-counting system for plastic scintillation detectors (PSDs). Methods: The PSD used in this study was made from a 1-mm diameter, 2-mm long BCF60 scintillating fiber (emission peak at 530 nm) coupled to a 2.6-m Eska GH-4001 clear plastic fiber. This PSD was coupled to either a fiber-taper-based photon-counting system (FTS) or a lens-based photon-counting system (LS). In the FTS, the fiber-taper was attached to a 2048 × 2048 pixel, uncooled Alta 4020 polychromatic CCD camera. The LS consisted of a 1600 × 1200 pixel Alta 2020 polychromatic CCD camera (cooled to −18 °C) with a 50-mm lens with f/# = 1. Dose measurements were made under the same conditions for each system (isocentric setup; depth of 1.5 cm in solid water using a 10 × 10 cm 2 field size and 6-MV photon beam). The performance of each system was determined and compared, using the chromatic Čerenkov removal method to account for the stem effects produced in the clear plastic fiber. Results: The FTS increased the light collected by a factor of 4 compared with the LS, for the same dose measurements. This gain was possible because the FTS was not limited by the optical aberration that comes with a lens system. Despite a 45 °C operating temperature difference between the systems, the SNR was 1.8–1.9 times higher in the FTS than in the LS, for blue and green channels respectively. Low-dose measurements of 1.0 and 0.5 cGy were obtained with an accuracy of 3.4% and 5.6%, respectively, in the FTS, compared with 5.8% and 15.9% in the LS. The FTS provided excellent dose measurement stability as a function of integration time, with at most a 1% difference at 5 cGy. Under the same conditions, the LS system produced a measurement difference between 2 and 3%. Conclusion: Our results showed that

  14. Coupling correction using closed orbit measurements

    International Nuclear Information System (INIS)

    Safranek, J.; Krinsky, S.

    1994-01-01

    The authors describe a coupling correction scheme they have developed and used to successfully reduce the vertical emittance of the NSLS X-Ray ring by a factor of 6 to below 2 A. This gives a vertical to horizontal emittance ratio of less than 0.2%. They find the strengths of 17 skew quadrupoles to simultaneously minimize the vertical dispersion and the coupling. As a measure of coupling they utilize the shift in vertical closed orbit resulting from a change in strength of a horizontal steering magnet. Experimental measurements confirm the reduced emittance

  15. ORILAM, a three-moment lognormal aerosol scheme for mesoscale atmospheric model: Online coupling into the Meso-NH-C model and validation on the Escompte campaign

    Science.gov (United States)

    Tulet, Pierre; Crassier, Vincent; Cousin, Frederic; Suhre, Karsten; Rosset, Robert

    2005-09-01

    Classical aerosol schemes use either a sectional (bin) or lognormal approach. Both approaches have particular capabilities and interests: the sectional approach is able to describe every kind of distribution, whereas the lognormal one makes assumption of the distribution form with a fewer number of explicit variables. For this last reason we developed a three-moment lognormal aerosol scheme named ORILAM to be coupled in three-dimensional mesoscale or CTM models. This paper presents the concept and hypothesis of a range of aerosol processes such as nucleation, coagulation, condensation, sedimentation, and dry deposition. One particular interest of ORILAM is to keep explicit the aerosol composition and distribution (mass of each constituent, mean radius, and standard deviation of the distribution are explicit) using the prediction of three-moment (m0, m3, and m6). The new model was evaluated by comparing simulations to measurements from the Escompte campaign and to a previously published aerosol model. The numerical cost of the lognormal mode is lower than two bins of the sectional one.

  16. Preliminary results on clinical effects of probiotic Lactobacillus salivarius LS01 in children affected by atopic dermatitis.

    Science.gov (United States)

    Niccoli, Antonio A; Artesi, Anna L; Candio, Francesco; Ceccarelli, Sara; Cozzali, Rita; Ferraro, Luigi; Fiumana, Donatella; Mencacci, Manuela; Morlupo, Maurizio; Pazzelli, Paola; Rossi, Laura; Toscano, Marco; Drago, Lorenzo

    2014-01-01

    The goal of this study was to evaluate the clinical efficacy of an intake of Lactobacillus salivarius LS01 (DSM 22775) for the treatment of atopic dermatitis (AD) in children. AD is an inflammatory and pruritic chronic relapsing skin disorder with multifactorial etiopathology. Some evidence suggests that probiotics may improve AD by modulating the immune system and the composition of intestinal microbiota. A total of 43 patients aged from 0 to 11 years were enrolled in the study (M/F ratio=1:1) and treated with the probiotic strain L. salivarius LS01. Clinical efficacy of probiotic treatment was assessed from baseline by changes in itch index and in the objective SCORAD/SCORAD index. Patients being given probiotic treatment showed a significant improvement in clinical parameters (SCORAD and itch values) from baseline. The reduction in SCORAD and itch index observed after 4 weeks of treatment also persisted after the cessation of probiotic supplementation. L. salivarius LS01 seems to be able to improve the quality of life of children affected by AD and, as a consequence, it may have promising clinical and research implications.

  17. Loft CIS analysis 2''-LS-118-AB outside containment penetration S5-D

    International Nuclear Information System (INIS)

    Morton, D.K.

    1978-01-01

    A stress analysis was performed on the 2''-LS-118-AB pipe system outside containment penetration S5-D. Deadweight, thermal expansion, and seismic loads were considered. The results indicate that this piping will meet ASME Section III, Class 2 requirements provided a U-bolt (S4) is installed as indicated in this report

  18. A unified inversion scheme to process multifrequency measurements of various dispersive electromagnetic properties

    Science.gov (United States)

    Han, Y.; Misra, S.

    2018-04-01

    Multi-frequency measurement of a dispersive electromagnetic (EM) property, such as electrical conductivity, dielectric permittivity, or magnetic permeability, is commonly analyzed for purposes of material characterization. Such an analysis requires inversion of the multi-frequency measurement based on a specific relaxation model, such as Cole-Cole model or Pelton's model. We develop a unified inversion scheme that can be coupled to various type of relaxation models to independently process multi-frequency measurement of varied EM properties for purposes of improved EM-based geomaterial characterization. The proposed inversion scheme is firstly tested in few synthetic cases in which different relaxation models are coupled into the inversion scheme and then applied to multi-frequency complex conductivity, complex resistivity, complex permittivity, and complex impedance measurements. The method estimates up to seven relaxation-model parameters exhibiting convergence and accuracy for random initializations of the relaxation-model parameters within up to 3-orders of magnitude variation around the true parameter values. The proposed inversion method implements a bounded Levenberg algorithm with tuning initial values of damping parameter and its iterative adjustment factor, which are fixed in all the cases shown in this paper and irrespective of the type of measured EM property and the type of relaxation model. Notably, jump-out step and jump-back-in step are implemented as automated methods in the inversion scheme to prevent the inversion from getting trapped around local minima and to honor physical bounds of model parameters. The proposed inversion scheme can be easily used to process various types of EM measurements without major changes to the inversion scheme.

  19. A Hybrid DGTD-MNA Scheme for Analyzing Complex Electromagnetic Systems

    KAUST Repository

    Li, Peng

    2015-01-07

    A hybrid electromagnetics (EM)-circuit simulator for analyzing complex systems consisting of EM devices loaded with nonlinear multi-port lumped circuits is described. The proposed scheme splits the computational domain into two subsystems: EM and circuit subsystems, where field interactions are modeled using Maxwell and Kirchhoff equations, respectively. Maxwell equations are discretized using a discontinuous Galerkin time domain (DGTD) scheme while Kirchhoff equations are discretized using a modified nodal analysis (MNA)-based scheme. The coupling between the EM and circuit subsystems is realized at the lumped ports, where related EM fields and circuit voltages and currents are allowed to “interact’’ via numerical flux. To account for nonlinear lumped circuit elements, the standard Newton-Raphson method is applied at every time step. Additionally, a local time-stepping scheme is developed to improve the efficiency of the hybrid solver. Numerical examples consisting of EM systems loaded with single and multiport linear/nonlinear circuit networks are presented to demonstrate the accuracy, efficiency, and applicability of the proposed solver.

  20. An Efficient Explicit Finite-Difference Scheme for Simulating Coupled Biomass Growth on Nutritive Substrates

    Directory of Open Access Journals (Sweden)

    G. F. Sun

    2015-01-01

    Full Text Available A novel explicit finite-difference (FD method is presented to simulate the positive and bounded development process of a microbial colony subjected to a substrate of nutrients, which is governed by a nonlinear parabolic partial differential equations (PDE system. Our explicit FD scheme is uniquely designed in such a way that it transfers the nonlinear terms in the original PDE into discrete sets of linear ones in the algebraic equation system that can be solved very efficiently, while ensuring the stability and the boundedness of the solution. This is achieved through (1 a proper design of intertwined FD approximations for the diffusion function term in both time and spatial variations and (2 the control of the time-step through establishing theoretical stability criteria. A detailed theoretical stability analysis is conducted to reveal that our FD method is indeed stable. Our examples verified the fact that the numerical solution can be ensured nonnegative and bounded to simulate the actual physics. Numerical examples have also been presented to demonstrate the efficiency of the proposed scheme. The present scheme is applicable for solving similar systems of PDEs in the investigation of the dynamics of biological films.

  1. Decoupled Scheme for Time-Dependent Natural Convection Problem II: Time Semidiscreteness

    Directory of Open Access Journals (Sweden)

    Tong Zhang

    2014-01-01

    stability and the corresponding optimal error estimates are presented. Furthermore, a decoupled numerical scheme is proposed by decoupling the nonlinear terms via temporal extrapolation; optimal error estimates are established. Finally, some numerical results are provided to verify the performances of the developed algorithms. Compared with the coupled numerical scheme, the decoupled algorithm not only keeps good accuracy but also saves a lot of computational cost. Both theoretical analysis and numerical experiments show the efficiency and effectiveness of the decoupled method for time-dependent natural convection problem.

  2. Adaptive spacetime method using Riemann jump conditions for coupled atomistic-continuum dynamics

    International Nuclear Information System (INIS)

    Kraczek, B.; Miller, S.T.; Haber, R.B.; Johnson, D.D.

    2010-01-01

    We combine the Spacetime Discontinuous Galerkin (SDG) method for elastodynamics with the mathematically consistent Atomistic Discontinuous Galerkin (ADG) method in a new scheme that concurrently couples continuum and atomistic models of dynamic response in solids. The formulation couples non-overlapping continuum and atomistic models across sharp interfaces by weakly enforcing jump conditions, for both momentum balance and kinematic compatibility, using Riemann values to preserve the characteristic structure of the underlying hyperbolic system. Momentum balances to within machine-precision accuracy over every element, on each atom, and over the coupled system, with small, controllable energy dissipation in the continuum region that ensures numerical stability. When implemented on suitable unstructured spacetime grids, the continuum SDG model offers linear computational complexity in the number of elements and powerful adaptive analysis capabilities that readily bridge between atomic and continuum scales in both space and time. A special trace operator for the atomic velocities and an associated atomistic traction field enter the jump conditions at the coupling interface. The trace operator depends on parameters that specify, at the scale of the atomic spacing, the position of the coupling interface relative to the atoms. In a key finding, we demonstrate that optimizing these parameters suppresses spurious reflections at the coupling interface without the use of non-physical damping or special boundary conditions. We formulate the implicit SDG-ADG coupling scheme in up to three spatial dimensions, and describe an efficient iterative solution scheme that outperforms common explicit schemes, such as the Velocity Verlet integrator. Numerical examples, in 1dxtime and employing both linear and nonlinear potentials, demonstrate the performance of the SDG-ADG method and show how adaptive spacetime meshing reconciles disparate time steps and resolves atomic-scale signals in

  3. Effective interactions and coupling schemes in nuclei

    International Nuclear Information System (INIS)

    Talmi, I.

    1994-01-01

    Eigenstates of the shell model are obtained by diagonalization of the Hamiltonian submatrix defined by a given shell model subspace. Matrix elements of the effective nuclear interaction can be determined from experiment in a consistent way. This approach was introduced in 1956 with the 38 Cl- 40 K spectra, has been applied in many cases and its latest success is in the s, d shell. This way, general features of the effective interaction have been determined. The T=1 interaction is diagonal in the seniority scheme as clearly demonstrated in proton 1g 9/2 n and 1h 11/2 n configurations and in the description of semimagic nuclei by generalized seniority. Apart from a strong and attractive pairing term, T=1 interactions are repulsive on the average. The T=0 interaction is attractive and is the origin of the central potential well in which nucleons are bound. It breaks seniority in a major way leading to deformed nuclei and rotational spectra. Such an interaction may be approximated by a quadrupole-quadrupole interaction which is the basis of the interacting boson model. Identical nucleons with pairing and quadrupole interactions cannot be models of actual nuclei. Symmetry properties of states with maximum T are very different from those of ground states of actual nuclei. The T=1 interaction between identical nucleons cannot be approximated by pairing and quadrupole interactions. The rich variety of nuclear spectra is due to the competition between seniority conserving T=1 interactions and the T=0 quadrupole interaction between protons and neutrons. (orig.)

  4. Numerical Simulation of Wind Turbine Rotors Autorotation by Using the Modified LS-STAG Immersed Boundary Method

    Directory of Open Access Journals (Sweden)

    Ilia K. Marchevsky

    2017-01-01

    Full Text Available A software package is developed for numerical simulation of wind turbine rotors autorotation by using the modified LS-STAG level-set/cut-cell immersed boundary method. The level-set function is used for immersed boundaries description. Algorithm of level-set function construction for complex-shaped airfoils, based on Bézier curves usage, is proposed. Also, algorithm for the level-set function recalculation at any time without reconstructing the Bézier curve for each new rotor position is described. The designed second-order Butterworth low-pass filter for aerodynamic torque filtration for simulations using coarse grids is presented. To verify the modified LS-STAG method, the flow past autorotating Savonius rotor with two blades was simulated at Re=1.96·105.

  5. Biodistribution, pharmacokinetic, and imaging studies with 186Re-labeled NR-LU-10 whole antibody in LS174T colonic tumor-bearing mice

    International Nuclear Information System (INIS)

    Goldrosen, M.H.; Biddle, W.C.; Pancook, J.; Bakshi, S.; Vanderheyden, J.L.; Fritzberg, A.R.; Morgan, A.C. Jr.; Foon, K.A.

    1990-01-01

    Biodistribution, pharmacokinetic, and radioimaging studies were performed with 186Re-labeled NR-LU-10 whole antibody in athymic nude mice bearing the LS174T tumor growing either s.c. or in an experimental hepatic metastasis model. NR-LU-10 is an IgG2b murine monoclonal antibody (MAb) that reacts with virtually all human tumors of epithelial origin. NR-BC-1, a IgG2b murine MAb that reacts with normal human B-cell and B malignancies, was used as an isotype-matched control. These MAbs were radiolabeled with 186Re by a preformed chelate approach by using the triamide thiolate ligand system. 186Re-labeled NR-LU-10 (50 microCi) was injected into nude mice bearing LS174T tumors growing s.c. Biodistribution studies revealed that the LS174T tumor retained the highest concentration of 186Re-labeled NR-LU-10 at day 6. The tumor:blood ratio ranged from 0.1:1 to 10.8:1 by day 6, the last day of analysis. In contrast the tumor:blood ratio of 186Re-labeled NR-BC-1, the isotype-matched MAb control, was 1:1 on day 6. Pharmacokinetic analysis indicated that the t1/2 beta of NR-LU-10 for blood and other tissues ranged from 21 to 25 h, while the t1/2 beta for the LS174T tumor averaged 52 h. The area under the curve for tumor compared to blood was 2.8- to 5.7-fold higher than the area under the curve for all other tissues and organs. The mean residence time for NR-LU-10 in blood and all other organs ranged from 23 to 26 h, while the mean residence time for NR-LU-10 in the LS174T tumor was 72 h. Scintigraphic images revealed selective uptake of the 186Re-labeled NR-LU-10, but not of the 186Re-labeled NR-BC-1, at the LS174T tumor site. Studies in an experimental model of hepatic metastasis revealed a similar selective pattern of 186Re-labeled NR-LU-10 accumulation. Scintigraphic images of the LS174T tumor growing within the athymic nude mouse liver were obtained

  6. A preliminary neutronic evaluation and depletion study of VHTR and LS-VHTR reactors using the codes: WIMSD5 and MCNPX

    International Nuclear Information System (INIS)

    Silva, Fabiano C.; Pereira, Claubia; Costa, Antonella Lombardi; Veloso, Maria Auxiliadora Fortini

    2009-01-01

    It is expected that, in the future, besides electricity generation, reactors should also develop secondary activities, such as hydrogen generation and seawater desalinization. Generation IV reactors are expected to possess special characteristics, like high safety, minimization of radioactive rejects amount and ability to use reprocessed fuel with non-proliferating projects in their cycles. Among the projects of IV generation reactors available nowadays, the (High Temperature Reactors) HTR, are highlighted due to these desirable characteristics. Under such circumstances, such reactor may be able to have significant higher thermal power ratings to be used for hydrogen production, without loose of safety, even in an emergency. For this work, we have chosen two HTR concepts of a prismatic reactor: (Very High Temperature Reactor) VHTR and the (Liquid Salted -Very High Temperature Reactor) LS-VHTR. The principal difference between them is the coolant. The VHTR uses helium gas as a coolant and have a burnup of 101,661 MWd/THM while the LS-VHTR uses low-pressure liquid coolant molten fluoride salt with a boiling point near 1500 de C working at 155,946 MWd/THM. The ultimate power output is limited by the capacity of the passive decay system; this capacity is limited by the reactor vessel temperature. The goal was to evaluate the neutronic behavior and fuel composition during the burnup using the codes (Winfrith Improved Multi-Group Scheme) WIMSD5 and the MCNPX2.6. The first, deterministic and the second, stochastic. For both reactors, burned fuel type 'C' coming from Angra-I nuclear plant, in Brazil, was used with 3.1% of initial enrichment, burnup to 33,000 MWd/THM using the ORIGEN2.1 code, divided in three steps of 11,000 MWd/THM, with an average density power of 37.75 MWd/THM and 5 years of cooling in pool. Finally, the fuel was reprocessed by Purex technique extracting 99.9% of Pu, and the desired amount of fissile material (15%) to achieve the final mixed oxide was

  7. Coupling constants deduced for the resonances in kaon photo-production

    International Nuclear Information System (INIS)

    Cheoun, M. K.; Kim, K. S.; Choi, T. K.

    2004-01-01

    We deduced the coupling constants of nucleon and hyperon resonances, which participate in kaon productions as intermediate states that are formed by electro-magnetic probes and that finally decay into hadronic final states. We used an isobaric model based on an effective Lagrangian approach to describe the processes, in which relevant coupling constants regarding related resonances are effectively determined by fitting available experimental data. Our scheme to deduce the coupling constants was as follows: First, we calculated the lower and the upper limits on the coupling constants by using the experimental decay data available until now and/or theoretical predictions, such as those from quark models and SU(3) symmetry. Second, we exploited those limits as physical constraints on our fitting scheme for the kaon photo-production data. Finally, the deduced values and regions of the coupling constants, which satisfy not only the reaction data but also the decay data, are presented as figures with respect to the strong and the electro-magnetic coupling constants, and their multiplicative values. Our results for the coupling constants give physical values that are more restricted than those allowed by the experimental data nowadays.

  8. Monitoring and preventing numerical oscillations in 3D simulations with coupled Monte Carlo codes

    International Nuclear Information System (INIS)

    Kotlyar, D.; Shwageraus, E.

    2014-01-01

    Highlights: • Conventional coupling methods used in all MC codes can be numerically unstable. • Application of new stochastic implicit (SIMP) methods may be required. • The implicit methods require additional computational effort. • Monitoring diagnostic of the numerical stability was developed here. • The procedure allows to create an hybrid explicit–implicit coupling scheme. - Abstract: Previous studies have reported that different schemes for coupling Monte Carlo (MC) neutron transport with burnup and thermal hydraulic feedbacks may potentially be numerically unstable. This issue can be resolved by application of implicit methods, such as the stochastic implicit mid-point (SIMP) methods. In order to assure numerical stability, the new methods do require additional computational effort. The instability issue however, is problem-dependent and does not necessarily occur in all cases. Therefore, blind application of the unconditionally stable coupling schemes, and thus incurring extra computational costs, may not always be necessary. In this paper, we attempt to develop an intelligent diagnostic mechanism, which will monitor numerical stability of the calculations and, if necessary, switch from simple and fast coupling scheme to more computationally expensive but unconditionally stable one. To illustrate this diagnostic mechanism, we performed a coupled burnup and TH analysis of a single BWR fuel assembly. The results indicate that the developed algorithm can be easily implemented in any MC based code for monitoring of numerical instabilities. The proposed monitoring method has negligible impact on the calculation time even for realistic 3D multi-region full core calculations

  9. Improving temporal resolution in fMRI using a 3D spiral acquisition and low rank plus sparse (L+S) reconstruction.

    Science.gov (United States)

    Petrov, Andrii Y; Herbst, Michael; Andrew Stenger, V

    2017-08-15

    Rapid whole-brain dynamic Magnetic Resonance Imaging (MRI) is of particular interest in Blood Oxygen Level Dependent (BOLD) functional MRI (fMRI). Faster acquisitions with higher temporal sampling of the BOLD time-course provide several advantages including increased sensitivity in detecting functional activation, the possibility of filtering out physiological noise for improving temporal SNR, and freezing out head motion. Generally, faster acquisitions require undersampling of the data which results in aliasing artifacts in the object domain. A recently developed low-rank (L) plus sparse (S) matrix decomposition model (L+S) is one of the methods that has been introduced to reconstruct images from undersampled dynamic MRI data. The L+S approach assumes that the dynamic MRI data, represented as a space-time matrix M, is a linear superposition of L and S components, where L represents highly spatially and temporally correlated elements, such as the image background, while S captures dynamic information that is sparse in an appropriate transform domain. This suggests that L+S might be suited for undersampled task or slow event-related fMRI acquisitions because the periodic nature of the BOLD signal is sparse in the temporal Fourier transform domain and slowly varying low-rank brain background signals, such as physiological noise and drift, will be predominantly low-rank. In this work, as a proof of concept, we exploit the L+S method for accelerating block-design fMRI using a 3D stack of spirals (SoS) acquisition where undersampling is performed in the k z -t domain. We examined the feasibility of the L+S method to accurately separate temporally correlated brain background information in the L component while capturing periodic BOLD signals in the S component. We present results acquired in control human volunteers at 3T for both retrospective and prospectively acquired fMRI data for a visual activation block-design task. We show that a SoS fMRI acquisition with an

  10. CMS outreach event to close LS1

    CERN Multimedia

    Achintya Rao

    2015-01-01

    CMS opened its doors to about 700 students from schools near CERN, who visited the detector on 16 and 17 February during the last major CMS outreach event of LS1.   Pellentesque sapien mi, pharetra vitae, auctor eu, congue sed, turpis. Enthusiastic CMS guides spent a day and a half showing the equally enthusiastic visitors, aged 10 to 18, the beauty of CMS and particle physics. The recently installed wheelchair lift was called into action and enabled a visitor who arrived on crutches to access the detector cavern unimpeded.  The CMS collaboration had previously devoted a day to school visits after the successful “Neighbourhood Days” in May 2014 and, encouraged by the turnout, decided to extend an invitation to local schools once again. The complement of nearly 40 guides and crowd marshals was aided by a support team that coordinated the transportation of the young guests and received them at Point 5, where a dedicated safety team including first-aiders, security...

  11. LS1 Report: the clouds are lifting

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    To combat the problem of electron clouds, which perturbate the environment of the particle beams in our accelerators, the Vacuum team have turned to amorphous carbon. This material is being applied to the interior of 16 magnets in the SPS during LS1 and will help prevent the formation of the secondary particles which are responsible for these clouds.   This photo shows the familiar coils of an SPS dipole magnet in brown. The vacuum chamber is the metallic rectangular part in the centre. The small wheeled device you can see in the vacuum chamber carries the hollow cathodes  along the length of the chamber. When a particle beam circulates at high energy in a vacuum chamber, it unavoidably generates secondary particles. These include electrons produced by the ionisation of residual molecules in the vacuum or indirectly generated by synchrotron radiation. When these electrons hit the surface of the vacuum chamber, they produce other electrons which, through an avalanche-like process, re...

  12. Calculating the LS factor of Universal Soil Loss Equation (USLE for the watershed of River Silver, Castelo-ES = Cálculo do fator LS da Equação Universal de Perdas de Solos (EUPS para a bacia do Rio da Prata, Castelo-ES

    Directory of Open Access Journals (Sweden)

    Luciano Melo Coutinho

    2014-01-01

    Full Text Available Erosion is considered the main cause of depletion of agricultural land, which generates approximate annual losses of billions of dollars in Brazil. Water erosion is the most common, caused by effective precipitation basin, since its potential is the main agent of reshaping the land. Universal Equation Soil Loss (USLE show great applicability to estimate erosion in watersheds from their physical and geographical elements (PS = R*K*L*S*C*P. The intensity of erosion can be influenced by the profile of the slope, measured by the length (L and grade of slope (S. The topographic factor (LS of the USLE is the most difficult to obtain for large and/or diverse relief areas. We calculated the spatial map of the LS factor Silver watershed (Castelo-ES from the processing of cartographic data in environment Geographic Information Systems (GIS. The relief of the study area was represented by interpolation from contour lines supported mapped hydrography, give the digital elevation model hydrologically consistent (MDEHC and declivity map. For generation of the LS factor was used to equation developed by Bertoni and Lombardi Neto (2005, suitable for slopes of different length and declivity. The Silver watershed has diversified relief, marked by flat and steep declivity areas, which indicates erosive vulnerability. The main values of LS were identified minimum (0, medium (8.2 and maximum (80.5. = A erosão é apontada como a principal causa do depauperamento de terras agrícolas, o que gera prejuízos anuais aproximados da ordem de bilhões de dólares no Brasil. A erosão hídrica é a mais comum, ocasionada pela precipitação efetiva em bacias, que devido ao seu potencial erosivo é o principal agente de remodelagem do terreno. A Equação Universal de Perdas de Solos (EUPS mostra-se de grande aplicabilidade para estimar a erosão de bacias hidrográficas a partir de seus elementos físicos e geográficos (PS = R*K*L*S*C*P. A intensidade da erosão pode sofrer

  13. Purification and genetic characterisation of the novel bacteriocin LS2 produced by the human oral strain Lactobacillus salivarius BGHO1.

    Science.gov (United States)

    Busarcevic, Milos; Dalgalarrondo, Michèle

    2012-08-01

    The aim of this study was to investigate the antimicrobial potential of Lactobacillus salivarius BGHO1, a human oral strain with probiotic characteristics and a broad inhibitory spectrum both against Gram-positive and Gram-negative pathogens. Here we present the bacteriocin LS2, an extremely pH- and heat-stable peptide with antilisterial activity. LS2 is a novel member of the class IId bacteriocins, unique among all currently characterised bacteriocins. It is somewhat similar to putative bacteriocins from several oral streptococci, including the cariogenic Streptococcus mutans. LS2 is a 41-amino-acid, highly hydrophobic cationic peptide of 4115.1Da that is sensitive to proteolytic enzymes. LS2 was purified from cells of strain BGHO1 by solvent extraction and reverse-phase chromatography. Mass spectrometry was used to determine the molecular mass of the purified peptide. N-terminal amino acid sequencing enabled identification of the LS2 structural gene bacls2 by a reverse genetics approach. Downstream of the bacls2 gene, two bacteriocin-like genes were found, named blp1a and blp1b, and one putative bacteriocin immunity gene named bimlp. We also present the identification of the 242-kb megaplasmid pMPHO1 by pulsed-field gel electrophoresis, which harbours the genes bacls2, blp1a, blp1b and bimlp. Two peptides with antimicrobial activity, whose approximate sizes corresponded to those of blp1a and blp1b, were identified only after culturing strain BGHO1 in a chemically defined medium. This study demonstrated the capacity of Lactobacillus salivarius BGHO1 to produce multiple bacteriocins and further established this strain as a promising probiotic candidate. Copyright © 2012 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  14. Effect of Co-overexpression of Nisin Key Genes on Nisin Production Improvement in Lactococcus lactis LS01.

    Science.gov (United States)

    Ni, Zhi-Jian; Zhang, Xiao-Yuan; Liu, Fei; Wang, Miao; Hao, Rong-Hua; Ling, Pei-Xue; Zhu, Xi-Qiang

    2017-06-01

    Nisin is a small antimicrobial peptide produced by several subset strains of Lactococcus lactis. To improve nisin yield in the producer L. lactis LS01, we proposed a successive fusion of nisA with nisRK and nisFEG into a single shuttle expression vector pMG36e under the control of the native strong constitutive promoter p32. Subsequently, the recombinant vectors were transplanted into the producer cell through electroporation. Nisin productivity was determined through sodium dodecyl sulfate-polyacrylamide gel electrophoresis and bioactivity assays. Expression of nisin peptide was detected by agar diffusion bioassay, and the transcriptional levels of the target genes involved in nisin biosynthesis were investigated via semi-quantitative reverse transcription PCR expression analysis using 16S ribosomal RNA (rRNA) as an internal control. Results suggested that the introduction of empty plasmid did not affect nisin production of L. lactis LS01, whereas by our rational construction and screening, the engineered strain co-overexpressing nisA, nisRK, and nisFEG achieved a maximum increment in bioactive nisin production with a yield of 2470 IU/ml in shake flasks and 4857 IU/ml in 1.0-l fermenters, which increased by approximately 66.3 and 52.6% (P < 0.05), respectively, compared with that of the original strain under the given fermentation conditions. Meanwhile, the transcriptional analysis revealed that the expression of most of these multicopy genes except nisE at transcriptional level were upregulated in the two recombinant strains (LS01/pAR and LS01/pARF), possibly contributing to the improved nisin production. Therefore, this study would provide a potential strategy to improve the economic benefits of nisin manufacture for large-scale industrial production.

  15. A Calderón multiplicative preconditioner for coupled surface-volume electric field integral equations

    KAUST Repository

    Bagci, Hakan

    2010-08-01

    A well-conditioned coupled set of surface (S) and volume (V) electric field integral equations (S-EFIE and V-EFIE) for analyzing wave interactions with densely discretized composite structures is presented. Whereas the V-EFIE operator is well-posed even when applied to densely discretized volumes, a classically formulated S-EFIE operator is ill-posed when applied to densely discretized surfaces. This renders the discretized coupled S-EFIE and V-EFIE system ill-conditioned, and its iterative solution inefficient or even impossible. The proposed scheme regularizes the coupled set of S-EFIE and V-EFIE using a Calderón multiplicative preconditioner (CMP)-based technique. The resulting scheme enables the efficient analysis of electromagnetic interactions with composite structures containing fine/subwavelength geometric features. Numerical examples demonstrate the efficiency of the proposed scheme. © 2006 IEEE.

  16. Simultaneous analysis in renormalization and factorization scheme dependences in perturbative QCD

    International Nuclear Information System (INIS)

    Nakkagawa, Hisao; Niegawa, Akira.

    1983-01-01

    Combined and thorough investigations of both the factorization and the renormalization scheme dependences of perturbative QCD calculations are given. Our findings are that (i) by introducing a multiscale-dependent coupling the simultaneous parametrization of both scheme-dependences can be accomplished, (ii) Stevenson's optimization method works quite well so that it gives a remarkable prediction which forces us to exponentiate ''everything'' with uncorrected subprocess cross sections, and (iii) the perturbation series in QCD may converge when Stevenson's principle of minimal sensitivity is taken into account at each order of perturbative approximation. (author)

  17. Advanced lattice Boltzmann scheme for high-Reynolds-number magneto-hydrodynamic flows

    Science.gov (United States)

    De Rosis, Alessandro; Lévêque, Emmanuel; Chahine, Robert

    2018-06-01

    Is the lattice Boltzmann method suitable to investigate numerically high-Reynolds-number magneto-hydrodynamic (MHD) flows? It is shown that a standard approach based on the Bhatnagar-Gross-Krook (BGK) collision operator rapidly yields unstable simulations as the Reynolds number increases. In order to circumvent this limitation, it is here suggested to address the collision procedure in the space of central moments for the fluid dynamics. Therefore, an hybrid lattice Boltzmann scheme is introduced, which couples a central-moment scheme for the velocity with a BGK scheme for the space-and-time evolution of the magnetic field. This method outperforms the standard approach in terms of stability, allowing us to simulate high-Reynolds-number MHD flows with non-unitary Prandtl number while maintaining accuracy and physical consistency.

  18. Application of stable adaptive schemes to nuclear reactor systems, (2)

    International Nuclear Information System (INIS)

    Kukuda, Toshio

    1979-01-01

    The parameter identification and adaptive control schemes applied in a previous study to a nonlinear point reactor are extended to the case of a loosely-coupled-core reactor with internal feedbacks, constituting a nonlinear overall system. Both schemes are shown to be stable, with the system newly represented on the pattern of the Model Reference Adaptive System (MRAS) with use made of the Lyapunov's method. For either parameter identification or adaptive control of a loosely-coupled-core reactor, there exists no canonical form of multiple input-multiple output system which can be directly applied for deriving the MRAS with the matrix version of the Kalman-Yakubovich lemma as it was in the case of the point reactor. This difficulty is circumvented by the practical assumption that the neutron density can be directly measured on each core as reactivity change is applied as input into the coupled core as a whole. For parameter identification, the model parameters are adaptively adjusted to those of each core, while for the adaptive control, plant parameters of each core can be adaptively compensated, again through control inputs, to asymptotically reduce the output error between the model and the plant. The point reactor is shown to correspond to a special case. (author)

  19. A New Scheme for Considering Soil Water-Heat Transport Coupling Based on Community Land Model: Model Description and Preliminary Validation

    Science.gov (United States)

    Wang, Chenghai; Yang, Kai

    2018-04-01

    Land surface models (LSMs) have developed significantly over the past few decades, with the result that most LSMs can generally reproduce the characteristics of the land surface. However, LSMs fail to reproduce some details of soil water and heat transport during seasonal transition periods because they neglect the effects of interactions between water movement and heat transfer in the soil. Such effects are critical for a complete understanding of water-heat transport within a soil thermohydraulic regime. In this study, a fully coupled water-heat transport scheme (FCS) is incorporated into the Community Land Model (version 4.5) to replaces its original isothermal scheme, which is more complete in theory. Observational data from five sites are used to validate the performance of the FCS. The simulation results at both single-point and global scale show that the FCS improved the simulation of soil moisture and temperature. FCS better reproduced the characteristics of drier and colder surface layers in arid regions by considering the diffusion of soil water vapor, which is a nonnegligible process in soil, especially for soil surface layers, while its effects in cold regions are generally inverse. It also accounted for the sensible heat fluxes caused by liquid water flow, which can contribute to heat transfer in both surface and deep layers. The FCS affects the estimation of surface sensible heat (SH) and latent heat (LH) and provides the details of soil heat and water transportation, which benefits to understand the inner physical process of soil water-heat migration.

  20. MECHANISM OF BIOACTIVITY OF LS2-FA GLASS-CERAMICS IN SBF AND DMEM MEDIUM

    Directory of Open Access Journals (Sweden)

    GABRIELA LUTIŠANOVÁ

    2012-09-01

    Full Text Available In this paper, the results of in vitro bioactivity of glass-ceramics in the Li2O–SiO2–CaO–P2O5–CaF2 (shorthand LS2-FA system immersed in two media (simulated body fluid (SBF and Dulbecco’s modified Eagle’s medium (DMEM are compared. Microprobe (EPMA and Scanning Electron Microscopy (SEM were used to detect the presence of a new phase on the surface and to characterize its layer. Inductively coupled plasma (ICP was used to monitor ion concentration changes in SBF with immersion time. The results show, that during the assay in vitro behaviour tests, the surface of the sample was partially dissolved and released of Si4+, Ca2+ and Li+ ions were released into the SBF medium. The results of surface characterization after in vitro tests revealed difference in the bioactivity of glass-ceramics with various time of immersion in SBF and DMEM. For the formation of an apatite-layer in an earlier testing period (1, 3 and 7 days, a pronounced difference was not observed between SBF and DMEM immersion. In the longer testing period in SBF (28 days, the apatite-layer was developed by periodic deposition of spherical bullets that covers the whole surface. The use of the acellular culture medium DMEM resulted in a delay at the start of precipitation.

  1. LS1 Report: achieving the unachievable

    CERN Multimedia

    Anaïs Schaeffer

    2013-01-01

    The dismantling and extraction of a defective DFBA module from LHC Point 6, announced a few weeks ago, has been completed without a hitch. The DFBAs in the LHC are unique and irreplaceable components that must be handled with care.   The Transport team extract the defective module in one of the two DFBAs at Point 6. This module was brought to the surface, where it is currently being repared. Dismantling and extracting part of an electrical feed box (DFBA) had not been planned and could not have been foreseen. Nonetheless, that is what had to be done. When the LS1 teams discovered that the bellows of one of the DFBAs in Sector 5-6 were damaged - and completely inaccessible - they were not exactly overwhelmed with solutions. In fact, they had only one option: to dismantle them and take them up to the surface. Step 1: measure the alignment of the module to be taken out in relation to the beam lines to ensure that when the DFBA is put back in, it is in the right position for the beam to pass thr...

  2. FERMI/LAT OBSERVATIONS OF LS 5039

    International Nuclear Information System (INIS)

    Abdo, A. A.; Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Baughman, B. M.; Bonamente, E.; Brigida, M.

    2009-01-01

    The first results from observations of the high-mass X-ray binary LS 5039 using the Fermi Gamma-ray Space Telescope data between 2008 August and 2009 June are presented. Our results indicate variability that is consistent with the binary period, with the emission being modulated with a period of 3.903 ± 0.005 days; the first detection of this modulation at GeV energies. The light curve is characterized by a broad peak around superior conjunction in agreement with inverse Compton scattering models. The spectrum is represented by a power law with an exponential cutoff, yielding an overall flux (100 MeV-300 GeV) of 4.9 ± 0.5(stat) ± 1.8(syst) x10 -7 photon cm -2 s -1 , with a cutoff at 2.1 ± 0.3(stat) ± 1.1(syst) GeV and photon index Γ = 1.9 ± 0.1(stat) ± 0.3(syst). The spectrum is observed to vary with orbital phase, specifically between inferior and superior conjunction. We suggest that the presence of a cutoff in the spectrum may be indicative of magnetospheric emission similar to the emission seen in many pulsars by Fermi.

  3. Evaluation of medium-chain-length polyhydroxyalkanoate production by Pseudomonas putida LS46 using biodiesel by-product streams.

    Science.gov (United States)

    Fu, Jilagamazhi; Sharma, Umesh; Sparling, Richard; Cicek, Nazim; Levin, David B

    2014-07-01

    Medium-chain-length polyhydroxyalkanoate (mcl-PHA) production by Pseudomonas putida LS46 was analyzed in shake-flask-based batch reactions, using pure chemical-grade glycerol (PG), biodiesel-derived "waste" glycerol (WG), and biodiesel-derived "waste" free fatty acids (WFA). Cell growth, substrate consumption, mcl-PHA accumulation within the cells, and the monomer composition of the synthesized biopolymers were monitored. The patterns of mcl-PHA synthesis in P. putida LS46 cells grown on PG and WG were similar but differed from that of cells grown with WFA. Polymer accumulation in glycerol-based cultures was stimulated by nitrogen limitation and plateaued after 48 h in both PG and WG cultures, with a total accumulation of 17.9% cell dry mass and 16.3% cell dry mass, respectively. In contrast, mcl-PHA synthesis was independent of nitrogen concentration in P. putida LS46 cells cultured with WFA, which accumulated to 29% cell dry mass. In all cases, the mcl-PHAs synthesized consisted primarily of 3-hydroxyoctanoate (C(8)) and 3-hydroxydecanoate (C(10)). WG and WFA supported similar or greater cell growth and mcl-PHA accumulation than PG under the experimental conditions used. These results suggest that biodiesel by-product streams could be used as low-cost carbon sources for sustainable mcl-PHA production.

  4. Multiple image encryption scheme based on pixel exchange operation and vector decomposition

    Science.gov (United States)

    Xiong, Y.; Quan, C.; Tay, C. J.

    2018-02-01

    We propose a new multiple image encryption scheme based on a pixel exchange operation and a basic vector decomposition in Fourier domain. In this algorithm, original images are imported via a pixel exchange operator, from which scrambled images and pixel position matrices are obtained. Scrambled images encrypted into phase information are imported using the proposed algorithm and phase keys are obtained from the difference between scrambled images and synthesized vectors in a charge-coupled device (CCD) plane. The final synthesized vector is used as an input in a random phase encoding (DRPE) scheme. In the proposed encryption scheme, pixel position matrices and phase keys serve as additional private keys to enhance the security of the cryptosystem which is based on a 4-f system. Numerical simulations are presented to demonstrate the feasibility and robustness of the proposed encryption scheme.

  5. Pressure correction schemes for compressible flows

    International Nuclear Information System (INIS)

    Kheriji, W.

    2011-01-01

    This thesis is concerned with the development of semi-implicit fractional step schemes, for the compressible Navier-Stokes equations; these schemes are part of the class of the pressure correction methods. The chosen spatial discretization is staggered: non conforming mixed finite elements (Crouzeix-Raviart or Rannacher-Turek) or the classic MA C scheme. An upwind finite volume discretization of the mass balance guarantees the positivity of the density. The positivity of the internal energy is obtained by discretizing the internal energy balance by an upwind finite volume scheme and b y coupling the discrete internal energy balance with the pressure correction step. A special finite volume discretization on dual cells is performed for the convection term in the momentum balance equation, and a renormalisation step for the pressure is added to the algorithm; this ensures the control in time of the integral of the total energy over the domain. All these a priori estimates imply the existence of a discrete solution by a topological degree argument. The application of this scheme to Euler equations raises an additional difficulty. Indeed, obtaining correct shocks requires the scheme to be consistent with the total energy balance, property which we obtain as follows. First of all, a local discrete kinetic energy balance is established; it contains source terms winch we somehow compensate in the internal energy balance. The kinetic and internal energy equations are associated with the dual and primal meshes respectively, and thus cannot be added to obtain a total energy balance; its continuous counterpart is however recovered at the limit: if we suppose that a sequence of discrete solutions converges when the space and time steps tend to 0, we indeed show, in 1D at least, that the limit satisfies a weak form of the equation. These theoretical results are comforted by numerical tests. Similar results are obtained for the baro-tropic Navier-Stokes equations. (author)

  6. Quantum correlations dynamics of three-qubit states coupled to an XY spin chain: Role of coupling strengths

    International Nuclear Information System (INIS)

    Yin Shao-Ying; Song Jie; Xu Xue-Xin; Zhou Ke-Ya; Liu Shu-Tian; Liu Qing-Xin

    2017-01-01

    We investigate the prominent impacts of coupling strengths on the evolution of entanglement and quantum discord for a three-qubit system coupled to an XY spin-chain environment. In the case of a pure W state, more robust, even larger nonzero quantum correlations can be obtained by tailoring the coupling strengths between the qubits and the environment. For a mixed state consisting of the GHZ and W states, the dynamics of entanglement and quantum discord can characterize the critical point of quantum phase transition. Remarkably, a large nonzero quantum discord is generally retained, while the nonzero entanglement can only be obtained as the system-environment coupling satisfies certain conditions. We also find that the impact of each qubit’s coupling strength on the quantum correlation dynamics strongly depends on the variation schemes of the system-environment couplings. (paper)

  7. Strong coupling phase in QED

    International Nuclear Information System (INIS)

    Aoki, Ken-ichi

    1988-01-01

    Existence of a strong coupling phase in QED has been suggested in solutions of the Schwinger-Dyson equation and in Monte Carlo simulation of lattice QED. In this article we recapitulate the previous arguments, and formulate the problem in the modern framework of the renormalization theory, Wilsonian renormalization. This scheme of renormalization gives the best understanding of the basic structure of a field theory especially when it has a multi-phase structure. We resolve some misleading arguments in the previous literature. Then we set up a strategy to attack the strong phase, if any. We describe a trial; a coupled Schwinger-Dyson equation. Possible picture of the strong coupling phase QED is presented. (author)

  8. Prediction of fetal lung maturity using the lecithin/sphingomyelin (L/S) ratio analysis with a simplified sample preparation, using a commercial microtip-column combined with mass spectrometric analysis.

    Science.gov (United States)

    Kwak, Ho-Seok; Chung, Hee-Jung; Choi, Young Sik; Min, Won-Ki; Jung, So Young

    2015-07-01

    Fetal lung maturity is estimated using the lecithin/sphingomyelin ratio (L/S ratio) in amniotic fluid and it is commonly measured with thin-layer chromatography (TLC). The TLC method is time consuming and technically difficult; however, it is widely used because there is no alternative. We evaluated a novel method for measuring the L/S ratio, which involves a tip-column with a cation-exchange resin and mass spectrometry. Phospholipids in the amniotic fluid were extracted using methanol and chloroform. Choline-containing phospholipids such as lecithin and sphingomyelin were purified by passing them through the tip-column. LC-MS/MS and MALDI-TOF were used to directly analyze the purified samples. The L/S ratio by mass spectrometry was calculated from the sum peak intensity of the six lecithin, and that of sphingomyelin 34:1. In 20 samples, the L/S ratio determined with TLC was significantly correlated with that obtained by LC-MS/MS and MALDI-TOF. There was a 100% concordance between the L/S ratio by TLC and that by LC-MS/MS (kappa value=1.0). The concordance between the L/S ratio by TLC and that by MALDI-TOF was also 100% (kappa value=1.0). Our method provides a faster, simpler, and more reliable assessment of fetal lung maturity. The L/S ratio measured by LC-MS/MS and MALDI-TOF offers a compelling alternative method to traditional TLC. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Lag Synchronization Between Two Coupled Networks via Open-Plus-Closed-Loop and Adaptive Controls

    International Nuclear Information System (INIS)

    Tong-Chun Hu; Yong-Qing Wu; Shi-Xing Li

    2016-01-01

    In this paper, we study lag synchronization between two coupled networks and apply two types of control schemes, including the open-plus-closed-loop (OPCL) and adaptive controls. We then design the corresponding control algorithms according to the OPCL and adaptive feedback schemes. With the designed controllers, we obtain two theorems on the lag synchronization based on Lyapunov stability theory and Barbalat's lemma. Finally we provide numerical examples to show the effectiveness of the obtained controllers and see that the adaptive control is stronger than the OPCL control when realizing the lag synchronization between two coupled networks with different coupling structures. (paper)

  10. Rigid Body Sampling and Individual Time Stepping for Rigid-Fluid Coupling of Fluid Simulation

    Directory of Open Access Journals (Sweden)

    Xiaokun Wang

    2017-01-01

    Full Text Available In this paper, we propose an efficient and simple rigid-fluid coupling scheme with scientific programming algorithms for particle-based fluid simulation and three-dimensional visualization. Our approach samples the surface of rigid bodies with boundary particles that interact with fluids. It contains two procedures, that is, surface sampling and sampling relaxation, which insures uniform distribution of particles with less iterations. Furthermore, we present a rigid-fluid coupling scheme integrating individual time stepping to rigid-fluid coupling, which gains an obvious speedup compared to previous method. The experimental results demonstrate the effectiveness of our approach.

  11. On Converting Secret Sharing Scheme to Visual Secret Sharing Scheme

    Directory of Open Access Journals (Sweden)

    Wang Daoshun

    2010-01-01

    Full Text Available Abstract Traditional Secret Sharing (SS schemes reconstruct secret exactly the same as the original one but involve complex computation. Visual Secret Sharing (VSS schemes decode the secret without computation, but each share is m times as big as the original and the quality of the reconstructed secret image is reduced. Probabilistic visual secret sharing (Prob.VSS schemes for a binary image use only one subpixel to share the secret image; however the probability of white pixels in a white area is higher than that in a black area in the reconstructed secret image. SS schemes, VSS schemes, and Prob. VSS schemes have various construction methods and advantages. This paper first presents an approach to convert (transform a -SS scheme to a -VSS scheme for greyscale images. The generation of the shadow images (shares is based on Boolean XOR operation. The secret image can be reconstructed directly by performing Boolean OR operation, as in most conventional VSS schemes. Its pixel expansion is significantly smaller than that of VSS schemes. The quality of the reconstructed images, measured by average contrast, is the same as VSS schemes. Then a novel matrix-concatenation approach is used to extend the greyscale -SS scheme to a more general case of greyscale -VSS scheme.

  12. Coupled Cluster Theory for Large Molecules

    DEFF Research Database (Denmark)

    Baudin, Pablo

    This thesis describes the development of local approximations to coupled cluster (CC) theory for large molecules. Two different methods are presented, the divide–expand–consolidate scheme (DEC), for the calculation of ground state energies, and a local framework denoted LoFEx, for the calculation...

  13. The polarizable embedding coupled cluster method

    DEFF Research Database (Denmark)

    Sneskov, Kristian; Schwabe, Tobias; Kongsted, Jacob

    2011-01-01

    We formulate a new combined quantum mechanics/molecular mechanics (QM/MM) method based on a self-consistent polarizable embedding (PE) scheme. For the description of the QM region, we apply the popular coupled cluster (CC) method detailing the inclusion of electrostatic and polarization effects...

  14. An electromagnetic induced transparency-like scheme for wireless power transfer using dielectric resonators

    Science.gov (United States)

    Elnaggar, Sameh Y.

    2017-02-01

    Similar to the hybridization of three atoms, three coupled resonators interact to form bonding, anti-bonding, and non-bonding modes. The non-bonding mode enables an electromagnetic induced transparency like transfer of energy. Here, the non-bonding mode, resulting from the strong electric coupling of two dielectric resonators and an enclosure, is exploited to show that it is feasible to transfer power over a distance comparable to the operating wavelength. In this scheme, the enclosure acts as a mediator. The strong coupling permits the excitation of the non-bonding mode with high purity. This approach is different from resonant inductive coupling, which works in the sub-wavelength regime. Optimal loads and the corresponding maximum efficiency are determined using two independent methods: Coupled Mode Theory and Circuit modelling. It is shown that, unlike resonant inductive coupling, the figure of merit depends on the enclosure quality and not on the load, which emphasizes the role of the enclosure as a mediator. Briefly after the input excitation is turned on, the energy in the receiver builds up via all coupled and spurious modes. As time elapses, all modes except the non-bonding cease to sustain. Due to the strong coupling between the dielectrics and the enclosure, such systems have unique properties such as high and uniform efficiency over large distances and minimal fringing fields. These properties suggest that electromagnetic induced transparency like schemes that rely on the use of dielectric resonators can be used to power autonomous systems inside an enclosure or find applications when exposure to the fields needs to be minimal. Finite Element computations are used to verify the theoretical predictions by determining the transfer efficiency, field profile, and coupling coefficients for two different systems. It is shown that the three resonators must be present for efficient power transfer; if one or more are removed, the transfer efficiency reduces

  15. Parallel Calculations in LS-DYNA

    Science.gov (United States)

    Vartanovich Mkrtychev, Oleg; Aleksandrovich Reshetov, Andrey

    2017-11-01

    Nowadays, structural mechanics exhibits a trend towards numeric solutions being found for increasingly extensive and detailed tasks, which requires that capacities of computing systems be enhanced. Such enhancement can be achieved by different means. E.g., in case a computing system is represented by a workstation, its components can be replaced and/or extended (CPU, memory etc.). In essence, such modification eventually entails replacement of the entire workstation, i.e. replacement of certain components necessitates exchange of others (faster CPUs and memory devices require buses with higher throughput etc.). Special consideration must be given to the capabilities of modern video cards. They constitute powerful computing systems capable of running data processing in parallel. Interestingly, the tools originally designed to render high-performance graphics can be applied for solving problems not immediately related to graphics (CUDA, OpenCL, Shaders etc.). However, not all software suites utilize video cards’ capacities. Another way to increase capacity of a computing system is to implement a cluster architecture: to add cluster nodes (workstations) and to increase the network communication speed between the nodes. The advantage of this approach is extensive growth due to which a quite powerful system can be obtained by combining not particularly powerful nodes. Moreover, separate nodes may possess different capacities. This paper considers the use of a clustered computing system for solving problems of structural mechanics with LS-DYNA software. To establish a range of dependencies a mere 2-node cluster has proven sufficient.

  16. Heterogeneous Coupling between Interdependent Lattices Promotes the Cooperation in the Prisoner's Dilemma Game.

    Directory of Open Access Journals (Sweden)

    Cheng-Yi Xia

    Full Text Available In the research realm of game theory, interdependent networks have extended the content of spatial reciprocity, which needs the suitable coupling between networks. However, thus far, the vast majority of existing works just assume that the coupling strength between networks is symmetric. This hypothesis, to some extent, seems inconsistent with the ubiquitous observation of heterogeneity. Here, we study how the heterogeneous coupling strength, which characterizes the interdependency of utility between corresponding players of both networks, affects the evolution of cooperation in the prisoner's dilemma game with two types of coupling schemes (symmetric and asymmetric ones. Compared with the traditional case, we show that heterogeneous coupling greatly promotes the collective cooperation. The symmetric scheme seems much better than the asymmetric case. Moreover, the role of varying amplitude of coupling strength is also studied on these two interdependent ways. Current findings are helpful for us to understand the evolution of cooperation within many real-world systems, in particular for the interconnected and interrelated systems.

  17. Heterogeneous Coupling between Interdependent Lattices Promotes the Cooperation in the Prisoner's Dilemma Game.

    Science.gov (United States)

    Xia, Cheng-Yi; Meng, Xiao-Kun; Wang, Zhen

    2015-01-01

    In the research realm of game theory, interdependent networks have extended the content of spatial reciprocity, which needs the suitable coupling between networks. However, thus far, the vast majority of existing works just assume that the coupling strength between networks is symmetric. This hypothesis, to some extent, seems inconsistent with the ubiquitous observation of heterogeneity. Here, we study how the heterogeneous coupling strength, which characterizes the interdependency of utility between corresponding players of both networks, affects the evolution of cooperation in the prisoner's dilemma game with two types of coupling schemes (symmetric and asymmetric ones). Compared with the traditional case, we show that heterogeneous coupling greatly promotes the collective cooperation. The symmetric scheme seems much better than the asymmetric case. Moreover, the role of varying amplitude of coupling strength is also studied on these two interdependent ways. Current findings are helpful for us to understand the evolution of cooperation within many real-world systems, in particular for the interconnected and interrelated systems.

  18. DSMC-LBM mapping scheme for rarefied and non-rarefied gas flows

    NARCIS (Netherlands)

    Di Staso, G.; Clercx, H.J.H.; Succi, S.; Toschi, F.

    2016-01-01

    We present the formulation of a kinetic mapping scheme between the Direct Simulation Monte Carlo (DSMC) and the Lattice Boltzmann Method (LBM) which is at the basis of the hybrid model used to couple the two methods in view of efficiently and accurately simulate isothermal flows characterized by

  19. Local and global synchronization in general complex dynamical networks with delay coupling

    International Nuclear Information System (INIS)

    Lu Jianquan; Ho, Daniel W.C.

    2008-01-01

    Local and global synchronization of complex dynamical networks are studied in this paper. Some simple yet generic criteria ensuring delay-independent and delay-dependent synchronization are derived in terms of linear matrix inequalities (LMIs), which can be verified easily via interior-point algorithm. The assumption that the coupling configuration matrix is symmetric and irreducible, which is frequently used in other literatures, is removed. A network with a fixed delay and a special coupling scheme is given as an example to illustrate the theoretical results and the effectiveness of the proposed synchronization scheme

  20. An improved conjugate gradient scheme to the solution of least squares SVM.

    Science.gov (United States)

    Chu, Wei; Ong, Chong Jin; Keerthi, S Sathiya

    2005-03-01

    The least square support vector machines (LS-SVM) formulation corresponds to the solution of a linear system of equations. Several approaches to its numerical solutions have been proposed in the literature. In this letter, we propose an improved method to the numerical solution of LS-SVM and show that the problem can be solved using one reduced system of linear equations. Compared with the existing algorithm for LS-SVM, the approach used in this letter is about twice as efficient. Numerical results using the proposed method are provided for comparisons with other existing algorithms.

  1. LS1 Report: Setting the bar high

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    This week LS1 successfully passed an important milestone: the first pressure test of a complete sector, sector 6-7.  The objective of this test was to check the mechanical integrity and overall leak-tightness of this section of the LHC by injecting it with pressurised helium.   The team in charge of the preparation and of the realisation of the pressure tests in sector 6-7. “Given the scale of the work and of the operations carried out during 2013, particularly in the framework of the SMACC project and of the repair of the compensators of the cryogenic distribution line (QRL), we need to revalidate the integrity of the systems before the accelerator starts up again,” explains Olivier Pirotte, who is in charge of the pressure tests (TE-CRG). The pressure tests are performed over a single day after two weeks of intensive activity to prepare and specially configure the cryogenic instrumentation in the tunnel, and the pressure within a sector is increased in stages,...

  2. LS1 Report: Thank you magnetic horn!

    CERN Multimedia

    Antonella Del Rosso & Katarina Anthony

    2014-01-01

    Experiments at the Antimatter Decelerator (AD) have been receiving beams since the beginning of this week. There is a crucial element at the heart of the chain that prepares the antiproton beam: the so-called magnetic horn, a delicate piece of equipment that had to be refurbished during LS1 and that is now showing just how well it can perform.   View from the top of the target and horn trolley, along the direction of the beam. Antiprotons for the AD are produced by smashing a beam of protons from the PS onto an iridium target. However, the particles produced by the nuclear interactions are emitted at very wide angles; without a focussing element, all these precious particles would be lost. “A magnetic horn is placed at the exit of the target to focus back a large fraction of the negative particles, including antiprotons, parallel to the beam line and with the right momentum,” explains Marco Calviani, physicist in the EN Department and the expert in charge of the AD targe...

  3. LS1 Report: ALICE ups the ante

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    SPS up and running... LHC almost cold... CCC Operators back at their desks... all telltale signs of the start of Run 2! For the experiments, that means there are just a few short months left for them to prepare for beams. The CERN Bulletin will be checking in with each of the Big Four to see how they are getting on during these closing months...   It has been a long road for the ALICE LS1 team. From major improvements to the 19 sub-detectors to a full re-cabling and replacement of LEP-era electrical infrastructure, no part of the ALICE cavern has gone untouched.* With the experiment set to close in early December, the teams are making finishing touches before turning their focus towards re-commissioning and calibration. "Earlier this week, we installed the last two modules of the di-jet calorimeter," explains Werner Riegler, ALICE technical coordinator. "These are the final parts of a 60 degree calorimeter extension that is installed opposite the present calorimeter, c...

  4. Numerical solution of special ultra-relativistic Euler equations using central upwind scheme

    Science.gov (United States)

    Ghaffar, Tayabia; Yousaf, Muhammad; Qamar, Shamsul

    2018-06-01

    This article is concerned with the numerical approximation of one and two-dimensional special ultra-relativistic Euler equations. The governing equations are coupled first-order nonlinear hyperbolic partial differential equations. These equations describe perfect fluid flow in terms of the particle density, the four-velocity and the pressure. A high-resolution shock-capturing central upwind scheme is employed to solve the model equations. To avoid excessive numerical diffusion, the considered scheme avails the specific information of local propagation speeds. By using Runge-Kutta time stepping method and MUSCL-type initial reconstruction, we have obtained 2nd order accuracy of the proposed scheme. After discussing the model equations and the numerical technique, several 1D and 2D test problems are investigated. For all the numerical test cases, our proposed scheme demonstrates very good agreement with the results obtained by well-established algorithms, even in the case of highly relativistic 2D test problems. For validation and comparison, the staggered central scheme and the kinetic flux-vector splitting (KFVS) method are also implemented to the same model. The robustness and efficiency of central upwind scheme is demonstrated by the numerical results.

  5. ATLAS TDAQ application gateway upgrade during LS1

    CERN Document Server

    KOROL, A; The ATLAS collaboration; BOGDANCHIKOV, A; BRASOLIN, F; CONTESCU, A C; DUBROV, S; HAFEEZ, M; LEE, C J; SCANNICCHIO, D A; TWOMEY, M; VORONKOV, A; ZAYTSEV, A

    2014-01-01

    The ATLAS Gateway service is implemented with a set of dedicated computer nodes to provide a fine-grained access control between CERN General Public Network (GPN) and ATLAS Technical Control Network (ATCN). ATCN connects the ATLAS online farm used for ATLAS Operations and data taking, including the ATLAS TDAQ (Trigger and Data Aquisition) and DCS (Detector Control System) nodes. In particular, it provides restricted access to the web services (proxy), general login sessions (via SSH and RDP protocols), NAT and mail relay from ATCN. At the Operating System level the implementation is based on virtualization technologies. Here we report on the Gateway upgrade during Long Shutdown 1 (LS1) period: it includes the transition to the last production release of the CERN Linux distribution (SLC6), the migration to the centralized configuration management system (based on Puppet) and the redesign of the internal system architecture.

  6. Effects of doping on ferroelectric properties and leakage current behavior of KNN-LT-LS thin films on SrTiO3 substrate

    Science.gov (United States)

    Abazari, M.; Safari, A.

    2009-05-01

    We report the effects of Ba, Ti, and Mn dopants on ferroelectric polarization and leakage current of (K0.44Na0.52Li0.04)(Nb0.84Ta0.1Sb0.06)O3 (KNN-LT-LS) thin films deposited by pulsed laser deposition. It is shown that donor dopants such as Ba2+, which increased the resistivity in bulk KNN-LT-LS, had an opposite effect in the thin film. Ti4+ as an acceptor B-site dopant reduces the leakage current by an order of magnitude, while the polarization values showed a slight degradation. Mn4+, however, was found to effectively suppress the leakage current by over two orders of magnitude while enhancing the polarization, with 15 and 23 μC/cm2 remanent and saturated polarization, whose values are ˜70% and 82% of the reported values for bulk composition. This phenomenon has been associated with the dual effect of Mn4+ in KNN-LT-LS thin film, by substituting both A- and B-site cations. A detailed description on how each dopant affects the concentrations of vacancies in the lattice is presented. Mn-doped KNN-LT-LS thin films are shown to be a promising candidate for lead-free thin films and applications.

  7. Nuclear Reactor Component Code CUPID-I: Numerical Scheme and Preliminary Assessment Results

    International Nuclear Information System (INIS)

    Cho, Hyoung Kyu; Jeong, Jae Jun; Park, Ik Kyu; Kim, Jong Tae; Yoon, Han Young

    2007-12-01

    A component scale thermal hydraulic analysis code, CUPID (Component Unstructured Program for Interfacial Dynamics), is being developed for the analysis of components of a nuclear reactor, such as reactor vessel, steam generator, containment, etc. It adopted three-dimensional, transient, two phase and three-field model. In order to develop the numerical schemes for the three-field model, various numerical schemes have been examined including the SMAC, semi-implicit ICE, SIMPLE, Row Scheme and so on. Among them, the ICE scheme for the three-field model was presented in the present report. The CUPID code is utilizing unstructured mesh for the simulation of complicated geometries of the nuclear reactor components. The conventional ICE scheme that was applied to RELAP5 and COBRA-TF, therefore, were modified for the application to the unstructured mesh. Preliminary calculations for the unstructured semi-implicit ICE scheme have been conducted for a verification of the numerical method from a qualitative point of view. The preliminary calculation results showed that the present numerical scheme is robust and efficient for the prediction of phase changes and flow transitions due to a boiling and a flashing. These calculation results also showed the strong coupling between the pressure and void fraction changes. Thus, it is believed that the semi-implicit ICE scheme can be utilized for transient two-phase flows in a component of a nuclear reactor

  8. Nuclear Reactor Component Code CUPID-I: Numerical Scheme and Preliminary Assessment Results

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyoung Kyu; Jeong, Jae Jun; Park, Ik Kyu; Kim, Jong Tae; Yoon, Han Young

    2007-12-15

    A component scale thermal hydraulic analysis code, CUPID (Component Unstructured Program for Interfacial Dynamics), is being developed for the analysis of components of a nuclear reactor, such as reactor vessel, steam generator, containment, etc. It adopted three-dimensional, transient, two phase and three-field model. In order to develop the numerical schemes for the three-field model, various numerical schemes have been examined including the SMAC, semi-implicit ICE, SIMPLE, Row Scheme and so on. Among them, the ICE scheme for the three-field model was presented in the present report. The CUPID code is utilizing unstructured mesh for the simulation of complicated geometries of the nuclear reactor components. The conventional ICE scheme that was applied to RELAP5 and COBRA-TF, therefore, were modified for the application to the unstructured mesh. Preliminary calculations for the unstructured semi-implicit ICE scheme have been conducted for a verification of the numerical method from a qualitative point of view. The preliminary calculation results showed that the present numerical scheme is robust and efficient for the prediction of phase changes and flow transitions due to a boiling and a flashing. These calculation results also showed the strong coupling between the pressure and void fraction changes. Thus, it is believed that the semi-implicit ICE scheme can be utilized for transient two-phase flows in a component of a nuclear reactor.

  9. AN ADVANCED LEAKAGE SCHEME FOR NEUTRINO TREATMENT IN ASTROPHYSICAL SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Perego, A. [Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 2, D-64289 Darmstadt (Germany); Cabezón, R. M. [Physics Department, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Käppeli, R., E-mail: albino.perego@physik.tu-darmstadt.de [Seminar for Applied Mathematics, ETH Zürich, Rämistrasse 101, 8092 Zürich (Switzerland)

    2016-04-15

    We present an Advanced Spectral Leakage (ASL) scheme to model neutrinos in the context of core-collapse supernovae (CCSNe) and compact binary mergers. Based on previous gray leakage schemes, the ASL scheme computes the neutrino cooling rates by interpolating local production and diffusion rates (relevant in optically thin and thick regimes, respectively) separately for discretized values of the neutrino energy. Neutrino trapped components are also modeled, based on equilibrium and timescale arguments. The better accuracy achieved by the spectral treatment allows a more reliable computation of neutrino heating rates in optically thin conditions. The scheme has been calibrated and tested against Boltzmann transport in the context of Newtonian spherically symmetric models of CCSNe. ASL shows a very good qualitative and a partial quantitative agreement for key quantities from collapse to a few hundreds of milliseconds after core bounce. We have proved the adaptability and flexibility of our ASL scheme, coupling it to an axisymmetric Eulerian and to a three-dimensional smoothed particle hydrodynamics code to simulate core collapse. Therefore, the neutrino treatment presented here is ideal for large parameter-space explorations, parametric studies, high-resolution tests, code developments, and long-term modeling of asymmetric configurations, where more detailed neutrino treatments are not available or are currently computationally too expensive.

  10. Control of the electromagnetic environment of a quantum emitter by shaping the vacuum field in a coupled-cavity system

    NARCIS (Netherlands)

    Johne, R.; Schutjens, H.A.W.; Fattahpoor, S.; Jin, C.; Fiore, A.

    2015-01-01

    We propose a scheme for the ultrafast control of the emitter-field coupling rate in cavity quantum electrodynamics. This is achieved by the control of the vacuum field seen by the emitter through a modulation of the optical modes in a coupled-cavity structure. The scheme allows the on-off switching

  11. Correlation effects beyond coupled cluster singles and doubles approximation through Fock matrix dressing.

    Science.gov (United States)

    Maitra, Rahul; Nakajima, Takahito

    2017-11-28

    We present an accurate single reference coupled cluster theory in which the conventional Fock operator matrix is suitably dressed to simulate the effect of triple and higher excitations within a singles and doubles framework. The dressing thus invoked originates from a second-order perturbative approximation of a similarity transformed Hamiltonian and induces higher rank excitations through local renormalization of individual occupied and unoccupied orbital lines. Such a dressing is able to recover a significant amount of correlation effects beyond singles and doubles approximation, but only with an economic n 5 additional cost. Due to the inclusion of higher rank excitations via the Fock matrix dressing, this method is a natural improvement over conventional coupled cluster theory with singles and doubles approximation, and this method would be demonstrated via applications on some challenging systems. This highly promising scheme has a conceptually simple structure which is also easily generalizable to a multi-reference coupled cluster scheme for treating strong degeneracy. We shall demonstrate that this method is a natural lowest order perturbative approximation to the recently developed iterative n-body excitation inclusive coupled cluster singles and doubles scheme [R. Maitra et al., J. Chem. Phys. 147, 074103 (2017)].

  12. Improving plasmonic waveguides coupling efficiency using nanoantennas

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Malureanu, Radu; Bouillard, Jean-Sebastien

    2012-01-01

    . The classical dipole antenna scheme can be improved by changing the nanoantenna geometry, adding constructive elements such as reflecting bars and mirrors and using arrays of antennas. The modelling designates that the coupling efficiency from a vertical fiber to a plasmonic waveguide can be improved more than......Plasmonic waveguides bear a lot of potential for photonic applications. However, one of the challenges for implementing them in devices is the low coupling efficiency to and from optical fibers. We report on our approach to facilitate the coupling efficiency with the use of metallic nanoantennas...... in 180 times in comparison with a direct fiber-waveguide coupling. Pros and cons of each configuration are discussed. Fabrication and characterisation results are reported....

  13. Problems of autonomy in coupled double-circuit systems of modern power plant automatic control systems

    International Nuclear Information System (INIS)

    Bilenko, V.A.; Davydov, N.I.

    1979-01-01

    Studied is the problem of autonomy in multicircuit systems of modern power plant automatic control systems; each part of the system has been carried out using the double-circuit scheme. Presented are the problems of neutralization of coupling between separate channels of power plant automatic control system. The conditions of autonomy in coupled double-circuit systems are obtained. The transfer functions of compensation devices are obtained and the variants of their connecting schemes are presented. Analyzed are possible variants of simplification of the coupled system adjustment process by its reduction to the series of consequent steps without using iteration procedures

  14. Using a zero-variance scheme to accelerate the fission source convergence in a Monte Carlo calculation

    International Nuclear Information System (INIS)

    Christoforou, S.; Hoogenboom, J. E.

    2009-01-01

    We have used Boltzmann entropy in order to test whether a zero-variance based scheme can speed up the fission source convergence in a Monte Carlo calculation. It is shown that the choice of the initial source distribution significantly influences the evolution of the source, even leading to cases where the source does not converge at all throughout the calculation. The results from a loosely coupled system based on the NEA/OECD source convergence benchmarks indicate that, when using a biasing scheme such as the one we have developed, there can be significant improvement in the convergence, up to 3 times faster, which coupled with an figure of merit improvement of 1.5 leads to more efficient calculations. (authors)

  15. Electron structure of molecules with very heavy atoms using effective core potentials

    International Nuclear Information System (INIS)

    Pitzer, K.S.

    1982-01-01

    Topics covered include effective potential, Hamiltonian for valence-electron motion, molecular calculations, spin-spin coupling, L-S coupling, numerical results of molecular calculations, and results of configuration-interaction Slater-orbital calculations in L-S coupling

  16. Influence of parameters detuning on induction motor NFO shaft-sensorless scheme

    Directory of Open Access Journals (Sweden)

    KULIC, F.

    2010-11-01

    Full Text Available In this paper, the parameter sensitivity analysis of shaft-sensorless induction motor drive with natural field orientation (NFO scheme is performed. NFO scheme calculates rotor flux position using the rotor flux vector reference only, does not require significant processor power and therefore it is suitable for low cost shaft sensorless drives. This concept also eliminates the need for sensitive stator voltage vector integration and it is usable in low rotor speed range. However, low speeds are coupled with low stator voltage amplitudes, which inflate the NFO scheme sensitivity to an error in stator resistance parameter. Similar problems can also take place if mutual inductance parameter is detuned, but this time in whole speed range. This paper investigates the influence of each parameter error on the NFO control steady state characteristics and dynamic performance.

  17. Scalability of Direct Solver for Non-stationary Cahn-Hilliard Simulations with Linearized time Integration Scheme

    KAUST Repository

    Woźniak, M.

    2016-06-02

    We study the features of a new mixed integration scheme dedicated to solving the non-stationary variational problems. The scheme is composed of the FEM approximation with respect to the space variable coupled with a 3-leveled time integration scheme with a linearized right-hand side operator. It was applied in solving the Cahn-Hilliard parabolic equation with a nonlinear, fourth-order elliptic part. The second order of the approximation along the time variable was proven. Moreover, the good scalability of the software based on this scheme was confirmed during simulations. We verify the proposed time integration scheme by monitoring the Ginzburg-Landau free energy. The numerical simulations are performed by using a parallel multi-frontal direct solver executed over STAMPEDE Linux cluster. Its scalability was compared to the results of the three direct solvers, including MUMPS, SuperLU and PaSTiX.

  18. Bilateral control of master-slave manipulators for ideal kinesthetic coupling

    International Nuclear Information System (INIS)

    Yokokohji, Yasuyoshi; Yoshikawa, Tsuneo

    1991-01-01

    The way to control master-slave manipulators affects considerably to the maneuverability of the master-slave systems. The ideal state of master-slave systems can be regarded that the operator can operate the system as if he were directly manipulating the object which is actually existing at the remote site. In other saying, the system must be coupled with the operator to give the ideal kinesthetic sense so that he can perceive the object. So far, several researches discussed about the ideal states of master-slave systems in their own descriptions. However, there is few exact discussion about how close the ideal state can be achieved actually or what kind of control scheme should be designed in order to achieve it. In this paper, we propose a control scheme which can achieve the ideal kinesthetic coupling with the operator and realize three ideal responses which were previously defined by the authors. Secondly, we show the stability of the system controlled by the proposed scheme by using the concept of passivity. We then discuss about the system stability when the sensor signals are pass through the filters. Lastly, the validity of the proposed scheme is confirmed by simulations. (author)

  19. Bilateral control of master-slave manipulators for ideal kinesthetic coupling

    Energy Technology Data Exchange (ETDEWEB)

    Yokokohji, Yasuyoshi; Yoshikawa, Tsuneo (Kyoto Univ. (Japan). Faculty of Engineering)

    1991-01-01

    The way to control master-slave manipulators affects considerably to the maneuverability of the master-slave systems. The ideal state of master-slave systems can be regarded that the operator can operate the system as if he were directly manipulating the object which is actually existing at the remote site. In other saying, the system must be coupled with the operator to give the ideal kinesthetic sense so that he can perceive the object. So far, several researches discussed about the ideal states of master-slave systems in their own descriptions. However, there is few exact discussion about how close the ideal state can be achieved actually or what kind of control scheme should be designed in order to achieve it. In this paper, we propose a control scheme which can achieve the ideal kinesthetic coupling with the operator and realize three ideal responses which were previously defined by the authors. Secondly, we show the stability of the system controlled by the proposed scheme by using the concept of passivity. We then discuss about the system stability when the sensor signals are pass through the filters. Lastly, the validity of the proposed scheme is confirmed by simulations. (author).

  20. SWATMOD-PREP: Graphical user interface for preparing coupled SWAT-modflow simulations

    Science.gov (United States)

    This paper presents SWATMOD-Prep, a graphical user interface that couples a SWAT watershed model with a MODFLOW groundwater flow model. The interface is based on a recently published SWAT-MODFLOW code that couples the models via mapping schemes. The spatial layout of SWATMOD-Prep guides the user t...

  1. Discrete quantum Fourier transform in coupled semiconductor double quantum dot molecules

    International Nuclear Information System (INIS)

    Dong Ping; Yang Ming; Cao Zhuoliang

    2008-01-01

    In this Letter, we present a physical scheme for implementing the discrete quantum Fourier transform in a coupled semiconductor double quantum dot system. The main controlled-R gate operation can be decomposed into many simple and feasible unitary transformations. The current scheme would be a useful step towards the realization of complex quantum algorithms in the quantum dot system

  2. Running couplings and operator mixing in the gravitational corrections to coupling constants

    International Nuclear Information System (INIS)

    Anber, Mohamed M.; Donoghue, John F.; El-Houssieny, Mohamed

    2011-01-01

    The use of a running coupling constant in renormalizable theories is well known, but the implementation of this idea for effective field theories with a dimensional coupling constant is, in general, less useful. Nevertheless, there are multiple attempts to define running couplings, including the effects of gravity, with varying conclusions. We sort through many of the issues involved, most particularly the idea of operator mixing and also the kinematics of crossing, using calculations in Yukawa and λφ 4 theories as illustrative examples. We remain in the perturbative regime. In some theories with a high permutation symmetry, such as λφ 4 , a reasonable running coupling can be defined. However, in most cases, such as Yukawa and gauge theories, a running coupling fails to correctly account for the energy dependence of the interaction strength. As a by-product we also contrast on-shell and off-shell renormalization schemes and show that operators which are normally discarded, such as those that vanish by the equations of motion, are required for off-shell renormalization of effective field theories. Our results suggest that the inclusion of gravity in the running of couplings is not useful or universal in the description of physical processes.

  3. Maximum-principle-satisfying space-time conservation element and solution element scheme applied to compressible multifluids

    KAUST Repository

    Shen, Hua; Wen, Chih-Yung; Parsani, Matteo; Shu, Chi-Wang

    2016-01-01

    A maximum-principle-satisfying space-time conservation element and solution element (CE/SE) scheme is constructed to solve a reduced five-equation model coupled with the stiffened equation of state for compressible multifluids. We first derive a sufficient condition for CE/SE schemes to satisfy maximum-principle when solving a general conservation law. And then we introduce a slope limiter to ensure the sufficient condition which is applicative for both central and upwind CE/SE schemes. Finally, we implement the upwind maximum-principle-satisfying CE/SE scheme to solve the volume-fraction-based five-equation model for compressible multifluids. Several numerical examples are carried out to carefully examine the accuracy, efficiency, conservativeness and maximum-principle-satisfying property of the proposed approach.

  4. Maximum-principle-satisfying space-time conservation element and solution element scheme applied to compressible multifluids

    KAUST Repository

    Shen, Hua

    2016-10-19

    A maximum-principle-satisfying space-time conservation element and solution element (CE/SE) scheme is constructed to solve a reduced five-equation model coupled with the stiffened equation of state for compressible multifluids. We first derive a sufficient condition for CE/SE schemes to satisfy maximum-principle when solving a general conservation law. And then we introduce a slope limiter to ensure the sufficient condition which is applicative for both central and upwind CE/SE schemes. Finally, we implement the upwind maximum-principle-satisfying CE/SE scheme to solve the volume-fraction-based five-equation model for compressible multifluids. Several numerical examples are carried out to carefully examine the accuracy, efficiency, conservativeness and maximum-principle-satisfying property of the proposed approach.

  5. Microbial Carbonate Precipitation by Synechococcus PCC8806, LS0519 and Synechocystis PCC6803 on Concrete Surfaces and in Low Saturation Solution

    Science.gov (United States)

    Zhu, T.; Lin, Y.; Dittrich, M.

    2015-12-01

    Microbial carbonate precipitation (MCP) by cyanobacteria has been recognized in a variety of environment such as freshwater, marine, cave, and even desert. Recently, their calcification potential has been tested in an emerging technology-- bioconcrete. This study is to explore the calcification by three cyanobacteria strains under different environmental conditions. Experiment A was carried out in 2mM NaHCO3 and 5mM CaCl2, with a cell concentration of 107 cells L-1. In experiment B, one side of the concrete surface was treated with bacteria and then immersed in the solution containing 0.4 mM NaHCO3 and 300 mM CaCl2. In experiment A, the pH of the abiotic condition remained constant around 8.55, while that of biotic conditions increased by 0.15 units in the presence of LS0519, and by 0.3 units in the presence of PCC8806 or PCC6803 within 8 hours. Over a period of 30 hours, PCC8806, LS0519 and PCC6803 removed 0.1, 0.12 and 0.2 mM calcium from the solution respectively. After 30 hours, the alkalinity of the solution decreased by 30 mg/L, 10 mg/L and 5 mg/L respectively in the presence of PCC6803, LS0519 and PCC8806. Under scanning electron microscopy (SEM), no precipitate was found in the abiotic condition, while calcium carbonate was associated by all the three strains. Among them, PCC6803 precipitated more carbonates. In experiment B, LS0519 and PCC8806 increased the pH with a value of 0.25, while PCC6803 increased the pH by 0.33 units. SEM shows LS0519 was less likely attached to the concrete surface. Neither did the precipitates on concrete surface differ from that in the abiotic condition. In comparison, PCC8806 and PCC6803 were closely associated with 8-μm porous precipitates. Cells were either found enclosed in precipitates or connecting two precipitates. In conclusion, all the three strains triggered the calcium carbonate precipitation. LS0519 has a little impact on the carbonate precipitation in the solution, but negligent influence on the concrete surface

  6. A positive and multi-element conserving time stepping scheme for biogeochemical processes in marine ecosystem models

    Science.gov (United States)

    Radtke, H.; Burchard, H.

    2015-01-01

    In this paper, an unconditionally positive and multi-element conserving time stepping scheme for systems of non-linearly coupled ODE's is presented. These systems of ODE's are used to describe biogeochemical transformation processes in marine ecosystem models. The numerical scheme is a positive-definite modification of the Runge-Kutta method, it can have arbitrarily high order of accuracy and does not require time step adaption. If the scheme is combined with a modified Patankar-Runge-Kutta method from Burchard et al. (2003), it also gets the ability to solve a certain class of stiff numerical problems, but the accuracy is restricted to second-order then. The performance of the new scheme on two test case problems is shown.

  7. Measurement scheme for purity based on two two-body gates

    Science.gov (United States)

    Nakazato, H.; Tanaka, T.; Yuasa, K.; Florio, G.; Pascazio, S.

    2012-04-01

    A scheme for measuring the purity of a quantum system with a finite number of levels is presented. The method makes use of two swap gates and hinges only on measurements performed on a reference system, prepared in a certain pure state and coupled with the target system. Neither tomographic methods, with the complete reconstruction of the state, nor interferometric setups are needed.

  8. Asymptotic diffusion limit of cell temperature discretisation schemes for thermal radiation transport

    Energy Technology Data Exchange (ETDEWEB)

    Smedley-Stevenson, Richard P., E-mail: richard.smedley-stevenson@awe.co.uk [AWE PLC, Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom); Department of Earth Science and Engineering, Imperial College London, SW7 2AZ (United Kingdom); McClarren, Ryan G., E-mail: rmcclarren@ne.tamu.edu [Department of Nuclear Engineering, Texas A & M University, College Station, TX 77843-3133 (United States)

    2015-04-01

    This paper attempts to unify the asymptotic diffusion limit analysis of thermal radiation transport schemes, for a linear-discontinuous representation of the material temperature reconstructed from cell centred temperature unknowns, in a process known as ‘source tilting’. The asymptotic limits of both Monte Carlo (continuous in space) and deterministic approaches (based on linear-discontinuous finite elements) for solving the transport equation are investigated in slab geometry. The resulting discrete diffusion equations are found to have nonphysical terms that are proportional to any cell-edge discontinuity in the temperature representation. Based on this analysis it is possible to design accurate schemes for representing the material temperature, for coupling thermal radiation transport codes to a cell centred representation of internal energy favoured by ALE (arbitrary Lagrange–Eulerian) hydrodynamics schemes.

  9. Asymptotic diffusion limit of cell temperature discretisation schemes for thermal radiation transport

    International Nuclear Information System (INIS)

    Smedley-Stevenson, Richard P.; McClarren, Ryan G.

    2015-01-01

    This paper attempts to unify the asymptotic diffusion limit analysis of thermal radiation transport schemes, for a linear-discontinuous representation of the material temperature reconstructed from cell centred temperature unknowns, in a process known as ‘source tilting’. The asymptotic limits of both Monte Carlo (continuous in space) and deterministic approaches (based on linear-discontinuous finite elements) for solving the transport equation are investigated in slab geometry. The resulting discrete diffusion equations are found to have nonphysical terms that are proportional to any cell-edge discontinuity in the temperature representation. Based on this analysis it is possible to design accurate schemes for representing the material temperature, for coupling thermal radiation transport codes to a cell centred representation of internal energy favoured by ALE (arbitrary Lagrange–Eulerian) hydrodynamics schemes

  10. A Newton-based Jacobian-free approach for neutronic-Monte Carlo/thermal-hydraulic static coupled analysis

    International Nuclear Information System (INIS)

    Mylonakis, Antonios G.; Varvayanni, M.; Catsaros, N.

    2017-01-01

    Highlights: •A Newton-based Jacobian-free Monte Carlo/thermal-hydraulic coupling approach is introduced. •OpenMC is coupled with COBRA-EN with a Newton-based approach. •The introduced coupling approach is tested in numerical experiments. •The performance of the new approach is compared with the traditional “serial” coupling approach. -- Abstract: In the field of nuclear reactor analysis, multi-physics calculations that account for the bonded nature of the neutronic and thermal-hydraulic phenomena are of major importance for both reactor safety and design. So far in the context of Monte-Carlo neutronic analysis a kind of “serial” algorithm has been mainly used for coupling with thermal-hydraulics. The main motivation of this work is the interest for an algorithm that could maintain the distinct treatment of the involved fields within a tight coupling context that could be translated into higher convergence rates and more stable behaviour. This work investigates the possibility of replacing the usually used “serial” iteration with an approximate Newton algorithm. The selected algorithm, called Approximate Block Newton, is actually a version of the Jacobian-free Newton Krylov method suitably modified for coupling mono-disciplinary solvers. Within this Newton scheme the linearised system is solved with a Krylov solver in order to avoid the creation of the Jacobian matrix. A coupling algorithm between Monte-Carlo neutronics and thermal-hydraulics based on the above-mentioned methodology is developed and its performance is analysed. More specifically, OpenMC, a Monte-Carlo neutronics code and COBRA-EN, a thermal-hydraulics code for sub-channel and core analysis, are merged in a coupling scheme using the Approximate Block Newton method aiming to examine the performance of this scheme and compare with that of the “traditional” serial iterative scheme. First results show a clear improvement of the convergence especially in problems where significant

  11. Improving Selectivity of 1D Bragg Resonator Using Coupling of Propagating and Trapped Waves

    CERN Document Server

    Ginzburg, N S; Peskov, Nikolay Yu; Sergeev, A S

    2004-01-01

    A novel 1D Bragg resonator based on coupling propagated and locked (quasi cut-off) modes should be tested in a JINR- IAP FEM-oscillator to improve selectivity over the transverse mode index. In this scheme the electron beam interacts with only propagating wave, and the latter is coupled with a quasi cut-off mode. This coupling can be realized by either helical or azimuthally-symmetric corrugation. The quasi cut-off mode provides the feedback in the system leading to the absolute instability and the self-excitation of the whole system while efficiency in the steady-state regime of generation is almost completely determined by the propagating mode, synchronous to the beam. Analytical consideration and numerical simulation show that the efficiency of such an FEM can be rather high. The main advantage of this scheme is provision of higher selectivity over the transverse mode index than traditional scheme of Bragg FEL that encourage increasing operating frequency for fixed transverse size of the interaction space.

  12. An explicit MOT-TDVIE scheme for analyzing electromagnetic field interactions on nonlinear scatterers

    KAUST Repository

    Ulku, Huseyin Arda

    2015-02-01

    An explicit marching on-in-time (MOT) based time domain electric field volume integral equation (TDVIE) solver for characterizing electromagnetic wave interactions on scatterers with nonlinear material properties is proposed. Discretization of the unknown electric field intensity and flux density is carried out by half and full Schaubert-Wilton-Glisson basis functions, respectively. Coupled system of spatially discretized TDVIE and the nonlinear constitutive relation between the field intensity and the flux density is integrated in time to compute the samples of the unknowns. An explicit PE(CE)m scheme is used for this purpose. Explicitness allows for \\'easy\\' incorporation of the nonlinearity as a function only to be evaluated on the right hand side of the coupled system of equations. A numerical example that demonstrates the applicability of the proposed MOT scheme to analyzing electromagnetic interactions on Kerr-nonlinear scatterers is presented. © 2015 IEEE.

  13. A numerical relativity scheme for cosmological simulations

    Science.gov (United States)

    Daverio, David; Dirian, Yves; Mitsou, Ermis

    2017-12-01

    Cosmological simulations involving the fully covariant gravitational dynamics may prove relevant in understanding relativistic/non-linear features and, therefore, in taking better advantage of the upcoming large scale structure survey data. We propose a new 3  +  1 integration scheme for general relativity in the case where the matter sector contains a minimally-coupled perfect fluid field. The original feature is that we completely eliminate the fluid components through the constraint equations, thus remaining with a set of unconstrained evolution equations for the rest of the fields. This procedure does not constrain the lapse function and shift vector, so it holds in arbitrary gauge and also works for arbitrary equation of state. An important advantage of this scheme is that it allows one to define and pass an adaptation of the robustness test to the cosmological context, at least in the case of pressureless perfect fluid matter, which is the relevant one for late-time cosmology.

  14. Electromagnetic wave propagation in time-dependent media with antisymmetric magnetoelectric coupling

    International Nuclear Information System (INIS)

    Lin, Shi-Rong; Zhang, Ruo-Yang; Ma, Yi-Rong; Jia, Wei; Zhao, Qing

    2016-01-01

    Highlights: • Time-dependent permittivity combined with antisymmetric magnetoelectric coupling will yield a novel linear birefringence. • Distinct dynamical behaviors of these two birefringent modes are analyzed. • As a new nonlinear optical effect, a scheme utilizing optical Kerr effect in moving media is proposed. - Abstract: This paper deals with electromagnetic wave propagation in time-dependent media with an antisymmetric magnetoelectric coupling and an isotropic time-dependent permittivity. We identify a new mechanism of linear birefringence, originated from the combined action of the time-dependent permittivity and the antisymmetric magnetoelectric coupling. Permittivity with linear and exponential temporal variations exemplifies the creation and control of these two distinct types of linear birefringent modes. As a novel nonlinear optical effect, a scheme utilizing optical Kerr effect in moving media is proposed for the realization of the predicted birefringence.

  15. Electromagnetic wave propagation in time-dependent media with antisymmetric magnetoelectric coupling

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Shi-Rong [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Zhang, Ruo-Yang [Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin 300071 (China); Ma, Yi-Rong; Jia, Wei [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Zhao, Qing, E-mail: qzhaoyuping@bit.edu.cn [School of Physics, Beijing Institute of Technology, Beijing 100081 (China)

    2016-07-29

    Highlights: • Time-dependent permittivity combined with antisymmetric magnetoelectric coupling will yield a novel linear birefringence. • Distinct dynamical behaviors of these two birefringent modes are analyzed. • As a new nonlinear optical effect, a scheme utilizing optical Kerr effect in moving media is proposed. - Abstract: This paper deals with electromagnetic wave propagation in time-dependent media with an antisymmetric magnetoelectric coupling and an isotropic time-dependent permittivity. We identify a new mechanism of linear birefringence, originated from the combined action of the time-dependent permittivity and the antisymmetric magnetoelectric coupling. Permittivity with linear and exponential temporal variations exemplifies the creation and control of these two distinct types of linear birefringent modes. As a novel nonlinear optical effect, a scheme utilizing optical Kerr effect in moving media is proposed for the realization of the predicted birefringence.

  16. Principle of Global Decoupling with Coupling Angle Modulation

    CERN Document Server

    Luo, Yun; Pilat, Fulvia Caterina; Roser, Thomas; Trbojevic, Dejan

    2005-01-01

    The global betatron decoupling on the ramp is an important issue for the operation of the Relativistic Heavy Ion Collider (RHIC). A new scheme coupling phase modulation is found. It introduces a rotating extra coupling into the coupled machine to detect the residual coupling. The eigentune responses are measured with a high resolution phase lock loop (PLL) system. From the minimum and maximum tune splits, the correction strengths are given. The time period occupied by one coupling phase modulation is less than 10 seconds. So it is a very promising solution for the global decoupling on the ramp. In this article the principle of the coupling phase modulation is given. The simulation with the smooth accelerator model is also done. The practical issues concerning its applications are discussed.

  17. Trajectory errors of different numerical integration schemes diagnosed with the MPTRAC advection module driven by ECMWF operational analyses

    Science.gov (United States)

    Rößler, Thomas; Stein, Olaf; Heng, Yi; Baumeister, Paul; Hoffmann, Lars

    2018-02-01

    The accuracy of trajectory calculations performed by Lagrangian particle dispersion models (LPDMs) depends on various factors. The optimization of numerical integration schemes used to solve the trajectory equation helps to maximize the computational efficiency of large-scale LPDM simulations. We analyzed global truncation errors of six explicit integration schemes of the Runge-Kutta family, which we implemented in the Massive-Parallel Trajectory Calculations (MPTRAC) advection module. The simulations were driven by wind fields from operational analysis and forecasts of the European Centre for Medium-Range Weather Forecasts (ECMWF) at T1279L137 spatial resolution and 3 h temporal sampling. We defined separate test cases for 15 distinct regions of the atmosphere, covering the polar regions, the midlatitudes, and the tropics in the free troposphere, in the upper troposphere and lower stratosphere (UT/LS) region, and in the middle stratosphere. In total, more than 5000 different transport simulations were performed, covering the months of January, April, July, and October for the years 2014 and 2015. We quantified the accuracy of the trajectories by calculating transport deviations with respect to reference simulations using a fourth-order Runge-Kutta integration scheme with a sufficiently fine time step. Transport deviations were assessed with respect to error limits based on turbulent diffusion. Independent of the numerical scheme, the global truncation errors vary significantly between the different regions. Horizontal transport deviations in the stratosphere are typically an order of magnitude smaller compared with the free troposphere. We found that the truncation errors of the six numerical schemes fall into three distinct groups, which mostly depend on the numerical order of the scheme. Schemes of the same order differ little in accuracy, but some methods need less computational time, which gives them an advantage in efficiency. The selection of the integration

  18. Cluster synchronization induced by one-node clusters in networks with asymmetric negative couplings

    International Nuclear Information System (INIS)

    Zhang, Jianbao; Ma, Zhongjun; Zhang, Gang

    2013-01-01

    This paper deals with the problem of cluster synchronization in networks with asymmetric negative couplings. By decomposing the coupling matrix into three matrices, and employing Lyapunov function method, sufficient conditions are derived for cluster synchronization. The conditions show that the couplings of multi-node clusters from one-node clusters have beneficial effects on cluster synchronization. Based on the effects of the one-node clusters, an effective and universal control scheme is put forward for the first time. The obtained results may help us better understand the relation between cluster synchronization and cluster structures of the networks. The validity of the control scheme is confirmed through two numerical simulations, in a network with no cluster structure and in a scale-free network

  19. Cluster synchronization induced by one-node clusters in networks with asymmetric negative couplings

    Science.gov (United States)

    Zhang, Jianbao; Ma, Zhongjun; Zhang, Gang

    2013-12-01

    This paper deals with the problem of cluster synchronization in networks with asymmetric negative couplings. By decomposing the coupling matrix into three matrices, and employing Lyapunov function method, sufficient conditions are derived for cluster synchronization. The conditions show that the couplings of multi-node clusters from one-node clusters have beneficial effects on cluster synchronization. Based on the effects of the one-node clusters, an effective and universal control scheme is put forward for the first time. The obtained results may help us better understand the relation between cluster synchronization and cluster structures of the networks. The validity of the control scheme is confirmed through two numerical simulations, in a network with no cluster structure and in a scale-free network.

  20. Loft CIS analysis 2''-LS-118-AB outside containment penetration S5-D

    Energy Technology Data Exchange (ETDEWEB)

    Morton, D.K.

    1978-09-28

    A stress analysis was performed on the 2''-LS-118-AB pipe system outside containment penetration S5-D. Deadweight, thermal expansion, and seismic loads were considered. The results indicate that this piping will meet ASME Section III, Class 2 requirements provided a U-bolt (S4) is installed as indicated in this report.

  1. Hypertension Knowledge-Level Scale (HK-LS): A Study on Development, Validity and Reliability

    OpenAIRE

    Erkoc, Sultan Baliz; Isikli, Burhanettin; Metintas, Selma; Kalyoncu, Cemalettin

    2012-01-01

    This study was conducted to develop a scale to measure knowledge about hypertension among Turkish adults. The Hypertension Knowledge-Level Scale (HK-LS) was generated based on content, face, and construct validity, internal consistency, test re-test reliability, and discriminative validity procedures. The final scale had 22 items with six sub-dimensions. The scale was applied to 457 individuals aged ≥18 years, and 414 of them were re-evaluated for test-retest reliability. The six sub-dimensio...

  2. International Symposium: “Scientific School of L.S. Vygotsky: Traditions and Innovations” and International ISCAR Summer University for PhD Students

    Directory of Open Access Journals (Sweden)

    Baykovskaya N.A.,

    2016-12-01

    Full Text Available The article represents a brief report on the work of the International Symposium: «Scientific School of L.S. Vygotsky: Traditions and Innovations» and VI th International ISCAR Summer University for PhD Students and young scholars, that were held in Moscow State University of Psychology & Education on June, 28 — July, 3 in 2016 in commemoration of the 120th anniversary of the great Russian psychologist L.S. Vygotsky. The main goals of the events organised by MSUPE include: analysis of the basic principles and the system of concepts of L.S. Vygotsky’s scientific school, discussion of the current state and the prospect for the development of the cultural-historical theory in Russia and abroad, integration of the ideas of the cultural-historical psychology and activity approach in various kinds of social and educational practices, as well as conducting research in the international scientific space. Symposium gathered the world’s leading experts and young scholars in the field of cultural-historical theory and activity approach from 19 countries, including United Kingdom, Australia, Switzerland, Greece, Brasil and USA.

  3. Development and Validation of an Instrument to Measure the Impact of Genetic Testing on Self-Concept in Lynch Syndrome (LS)

    Science.gov (United States)

    Esplen, Mary Jane; Stuckless, Noreen; Wong, Jiahui; Gallinger, Steve; Aronson, Melyssa; Rothenmund, Heidi; Semotiuk, Kara; Stokes, Jackie; Way, Chris; Green, Jane; Butler, Kate; Petersen, Helle Vendel

    2011-01-01

    Background A positive genetic test result may impact on a person’s self-concept and affect quality of life. Purpose The purpose of the study was to develop a self concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer- Lynch Syndrome (LS). Methods Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers. Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. Results A 20 item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale demonstrated excellent reliability (Cronbach’s α = .93), good convergent validity by a high correlation with impact of event scale (r(102) = .55, pRosenberg Self-Esteem Scale (r(108) = −.59, pscale’s performance was stable across participant characteristics. Conclusions This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies. PMID:21883167

  4. Evaluation of Material Models within LS-DYNA(Registered TradeMark) for a Kevlar/Epoxy Composite Honeycomb

    Science.gov (United States)

    Polanco, Michael A.; Kellas, Sotiris; Jackson, Karen

    2009-01-01

    The performance of material models to simulate a novel composite honeycomb Deployable Energy Absorber (DEA) was evaluated using the nonlinear explicit dynamic finite element code LS-DYNA(Registered TradeMark). Prototypes of the DEA concept were manufactured using a Kevlar/Epoxy composite material in which the fibers are oriented at +/-45 degrees with respect to the loading axis. The development of the DEA has included laboratory tests at subcomponent and component levels such as three-point bend testing of single hexagonal cells, dynamic crush testing of single multi-cell components, and impact testing of a full-scale fuselage section fitted with a system of DEA components onto multi-terrain environments. Due to the thin nature of the cell walls, the DEA was modeled using shell elements. In an attempt to simulate the dynamic response of the DEA, it was first represented using *MAT_LAMINATED_COMPOSITE_FABRIC, or *MAT_58, in LS-DYNA. Values for each parameter within the material model were generated such that an in-plane isotropic configuration for the DEA material was assumed. Analytical predictions showed that the load-deflection behavior of a single-cell during three-point bending was within the range of test data, but predicted the DEA crush response to be very stiff. In addition, a *MAT_PIECEWISE_LINEAR_PLASTICITY, or *MAT_24, material model in LS-DYNA was developed, which represented the Kevlar/Epoxy composite as an isotropic elastic-plastic material with input from +/-45 degrees tensile coupon data. The predicted crush response matched that of the test and localized folding patterns of the DEA were captured under compression, but the model failed to predict the single-cell three-point bending response.

  5. Simulation of coupled flow and mechanical deformation using IMplicit Pressure-Displacement Explicit Saturation (IMPDES) scheme

    KAUST Repository

    El-Amin, Mohamed; Negara, Ardiansyah; Salama, Amgad; Sun, Shuyu

    2012-01-01

    cell along the entire domain is given by the implicit difference equation. Also, the deformation equations are discretized implicitly. Using the obtained pressure, velocity is evaluated explicitly, while, using the upwind scheme, the saturation

  6. Quantum state transfer with untunable couplings

    International Nuclear Information System (INIS)

    Gagnebin, P. K.; Skinner, S. R.; Behrman, E. C.; Steck, J. E.

    2007-01-01

    We present a general scheme for implementing bidirectional quantum state transfer in a quantum swapping channel. Unlike many other schemes for quantum computation and communication, our method does not require qubit couplings to be switched on and off. The only control variable is the bias acting on individual qubits. We show how to derive the parameters of the system (fixed and variable) such that perfect state transfer can be achieved. Since these parameters vary linearly with the pulse width, our scheme allows flexibility in the time scales under which qubits evolve. Unlike quantum spin networks, our scheme allows the transmission of several quantum states at a time, requiring only a two qubit separation between quantum states. By pulsing the biases of several qubits at the same time, we show that only eight bias control lines are required to achieve state transfer along a channel of arbitrary length. Furthermore, when the information to be transferred is purely classical in nature, only three bias control lines are required, greatly simplifying the circuit complexity

  7. Current multiplier to improved generator-to-load coupling for pulse-power generators

    International Nuclear Information System (INIS)

    Chuvatin, A.S.; Rudakov, L.I.; Weber, B.V.; Bayol, F.; Cadiergues, R.

    2005-01-01

    The circuit presented improves the coupling of existing and future pulsed power generators to physical loads. The efficiency of the proposed current multiplication scheme could theoretically exceed the values for a typical direct load-to-generator circuit. The scheme could be beneficial for use in actual applications and two examples of such applications are given [ru

  8. A hybrid system of a membrane oscillator coupled to ultracold atoms

    Science.gov (United States)

    Kampschulte, Tobias

    2015-05-01

    The control over micro- and nanomechanical oscillators has recently made impressive progress. First experiments demonstrated ground-state cooling and single-phonon control of high-frequency oscillators using cryogenic cooling and techniques of cavity optomechanics. Coupling engineered mechanical structures to microscopic quantum system with good coherence properties offers new possibilities for quantum control of mechanical vibrations, precision sensing and quantum-level signal transduction. Ultracold atoms are an attractive choice for such hybrid systems: Mechanical can either be coupled to the motional state of trapped atoms, which can routinely be ground-state cooled, or to the internal states, for which a toolbox of coherent manipulation and detection exists. Furthermore, atomic collective states with non-classical properties can be exploited to infer the mechanical motion with reduced quantum noise. Here we use trapped ultracold atoms to sympathetically cool the fundamental vibrational mode of a Si3N4 membrane. The coupling of membrane and atomic motion is mediated by laser light over a macroscopic distance and enhanced by an optical cavity around the membrane. The observed cooling of the membrane from room temperature to 650 +/- 230 mK shows that our hybrid mechanical-atomic system operates at a large cooperativity. Our scheme could provide ground-state cooling and quantum control of low-frequency oscillators such as levitated nanoparticles, in a regime where purely optomechanical techniques cannot reach the ground state. Furthermore, we will present a scheme where an optomechanical system is coupled to internal states of ultracold atoms. The mechanical motion is translated into a polarization rotation which drives Raman transitions between atomic ground states. Compared to the motional-state coupling, the new scheme enables to couple atoms to high-frequency structures such as optomechanical crystals.

  9. Sum rule and hydrodynamic analyses of the velocity autocorrelation function in strongly coupled plasmas

    International Nuclear Information System (INIS)

    Nagano, Seido; Ichimaru, Setsuo

    1980-01-01

    The memory function for the velocity autocorrelation function in a strongly coupled, one-component plasma is analyzed in the short time and long time domains, respectively, with the aid of the frequency-moment sum rules and the hydrodynamic consideration evoking the idea of the generalized Stokes friction. A series of interpolation schemes with successively improved accuracies are then introduced. Numerical investigations of those interpolation schemes clarify the physical origin of the three different types of the velocity autocorrelation function observed in the molecular dynamics simulation at different regimes of the coupling constant. (author)

  10. Mimicking Natural Photosynthesis: Solar to Renewable H2 Fuel Synthesis by Z-Scheme Water Splitting Systems.

    Science.gov (United States)

    Wang, Yiou; Suzuki, Hajime; Xie, Jijia; Tomita, Osamu; Martin, David James; Higashi, Masanobu; Kong, Dan; Abe, Ryu; Tang, Junwang

    2018-05-23

    Visible light-driven water splitting using cheap and robust photocatalysts is one of the most exciting ways to produce clean and renewable energy for future generations. Cutting edge research within the field focuses on so-called "Z-scheme" systems, which are inspired by the photosystem II-photosystem I (PSII/PSI) coupling from natural photosynthesis. A Z-scheme system comprises two photocatalysts and generates two sets of charge carriers, splitting water into its constituent parts, hydrogen and oxygen, at separate locations. This is not only more efficient than using a single photocatalyst, but practically it could also be safer. Researchers within the field are constantly aiming to bring systems toward industrial level efficiencies by maximizing light absorption of the materials, engineering more stable redox couples, and also searching for new hydrogen and oxygen evolution cocatalysts. This review provides an in-depth survey of relevant Z-schemes from past to present, with particular focus on mechanistic breakthroughs, and highlights current state of the art systems which are at the forefront of the field.

  11. On the Toyota LS400 Car Electronic Air Suspension System (TEMS)%浅谈丰田LS400轿车电子空气悬架系统(TEMS)

    Institute of Scientific and Technical Information of China (English)

    池杜旺

    2014-01-01

    随着汽车电子技术的不断发展以及人们对汽车舒适性的要求越来越高,一般的悬架系统已经很难满足高要求的现代车主们,而在如奥迪A8,奔驰S600,LS400等一些高档的轿车上面就采用了更为舒适,控制功能更强的电子悬架系统.

  12. Coupling-induced cooperative behaviour in dynamic ferromagnetic cores in the presence of a noise floor

    International Nuclear Information System (INIS)

    Bulsara, Adi R.; Lindner, John F.; In, Visarath; Kho, Andy; Baglio, Salvatore; Sacco, Vincenzo; Ando, Bruno; Longhini, Patrick; Palacios, Antonio; Rappel, Wouter-Jan

    2006-01-01

    Recently, we have shown the emergence of oscillations in overdamped undriven nonlinear dynamic systems subject to carefully crafted coupling schemes and operating conditions. Here, we summarize experimental results obtained on a system of N=3 coupled ferromagnetic cores, the underpinning of a 'coupled-core fluxgate magnetometer' (CCFM); the oscillatory behaviour is triggered when the coupling constant exceeds a threshold value (bifurcation point), and the oscillation frequency exhibits a characteristic scaling behaviour with the 'separation' of the coupling constant from its threshold value, as well as with an external target DC magnetic flux signal. The oscillations, which can be induced at frequencies ranging from a few Hz to high-kHz, afford a new detection scheme for weak target magnetic signals. We also present the first (numerical) results on the effects of a (Gaussian, exponentially correlated) noise floor on the spectral properties of the system response

  13. Coupling-induced cooperative behaviour in dynamic ferromagnetic cores in the presence of a noise floor

    Energy Technology Data Exchange (ETDEWEB)

    Bulsara, Adi R. [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull Street, San Diego, CA 92152-5001 (United States)]. E-mail: bulsara@spawar.navy.mil; Lindner, John F. [Physics Department, College of Wooster, Wooster, OH 44691 (United States); In, Visarath [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull Street, San Diego, CA 92152-5001 (United States); Kho, Andy [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull Street, San Diego, CA 92152-5001 (United States); Baglio, Salvatore [Dipartimento di Ingegneria Elettrica Elettronica e dei Sistemi, Universita degli Studi di Catania, Viale A. Doria 6, 95125 Catania (Italy); Sacco, Vincenzo [Dipartimento di Ingegneria Elettrica Elettronica e dei Sistemi, Universita degli Studi di Catania, Viale A. Doria 6, 95125 Catania (Italy); Ando, Bruno [Dipartimento di Ingegneria Elettrica Elettronica e dei Sistemi, Universita degli Studi di Catania, Viale A. Doria 6, 95125 Catania (Italy); Longhini, Patrick [Nonlinear Dynamics Group, Department of Mathematics, San Diego State University, San Diego, CA 92182 (United States); Palacios, Antonio [Nonlinear Dynamics Group, Department of Mathematics, San Diego State University, San Diego, CA 92182 (United States); Rappel, Wouter-Jan [Physics Department, University of California at San Diego, La Jolla, CA 929093 (United States)

    2006-04-17

    Recently, we have shown the emergence of oscillations in overdamped undriven nonlinear dynamic systems subject to carefully crafted coupling schemes and operating conditions. Here, we summarize experimental results obtained on a system of N=3 coupled ferromagnetic cores, the underpinning of a 'coupled-core fluxgate magnetometer' (CCFM); the oscillatory behaviour is triggered when the coupling constant exceeds a threshold value (bifurcation point), and the oscillation frequency exhibits a characteristic scaling behaviour with the 'separation' of the coupling constant from its threshold value, as well as with an external target DC magnetic flux signal. The oscillations, which can be induced at frequencies ranging from a few Hz to high-kHz, afford a new detection scheme for weak target magnetic signals. We also present the first (numerical) results on the effects of a (Gaussian, exponentially correlated) noise floor on the spectral properties of the system response.

  14. The Optimal Income Taxation of Couples

    DEFF Research Database (Denmark)

    Kleven, Henrik Jacobsen; Kreiner, Claus Thustrup; Saez, Emmanuel

    2009-01-01

    This paper analyzes the general nonlinear optimal income tax for couples, a multidimensional screening problem. Each couple consists of a primary earner who always participates in the labor market, but makes an hours-of-work choice, and a secondary earner who chooses whether or not to work....... If second-earner participation is a signal of the couple being better (worse) off, we prove that optimal tax schemes display a positive tax (subsidy) on secondary earnings and that the tax (subsidy) on secondary earnings decreases with primary earnings and converges to zero asymptotically. We present...... calibrated microsimulations for the United Kingdom showing that decreasing tax rates on secondary earnings is quantitatively significant and consistent with actual income tax and transfer programs....

  15. Prospective study of toric IOL outcomes based on the Lenstar LS 900® dual zone automated keratometer

    Directory of Open Access Journals (Sweden)

    Gundersen Kjell

    2012-07-01

    Full Text Available Abstract Background To establish clinical expectations when using the Lenstar LS 900® dual-zone automated keratometer for surgery planning of toric intraocular lenses. Methods Fifty eyes were measured with the Lenstar LS 900® dual-zone automated keratometer . Surgical planning was performed with the data from this device and the known surgically induced astigmatism of the surgeon. Post-operative refractions and visual acuity were measured at 1 month and 3 months. Results Clinical outcomes from 43 uncomplicated surgeries showed an average post-operative refractive astigmatism of 0.44D ±0.25D. Over 70% of eyes had 0.50D or less of refractive astigmatism and no eye had more than 1.0D of refractive astigmatism. Uncorrected visual acuity was 20/32 or better in all eyes at 3 months, with 70% of eyes 20/20 or better. A significantly higher number of eyes had 0.75D or more of post-operative refractive astigmatism when the standard deviation of the pre-operative calculated corneal astigmatism angle, reported by the keratometer, was > 5 degrees. Conclusions In this single-site study investigating the use of the keratometry from the Lenstar LS 900® for toric IOL surgical planning, clinical outcomes appear equivalent to those reported in the literature for manual keratometry and somewhat better than has been reported for some previous automated instruments. A high standard deviation in the pre-operative calculated astigmatism angle, as reported by the keratometer, appears to increase the likelihood of higher post-operative refractive astigmatism.

  16. A gradient stable scheme for a phase field model for the moving contact line problem

    KAUST Repository

    Gao, Min

    2012-02-01

    In this paper, an efficient numerical scheme is designed for a phase field model for the moving contact line problem, which consists of a coupled system of the Cahn-Hilliard and Navier-Stokes equations with the generalized Navier boundary condition [1,2,4]. The nonlinear version of the scheme is semi-implicit in time and is based on a convex splitting of the Cahn-Hilliard free energy (including the boundary energy) together with a projection method for the Navier-Stokes equations. We show, under certain conditions, the scheme has the total energy decaying property and is unconditionally stable. The linearized scheme is easy to implement and introduces only mild CFL time constraint. Numerical tests are carried out to verify the accuracy and stability of the scheme. The behavior of the solution near the contact line is examined. It is verified that, when the interface intersects with the boundary, the consistent splitting scheme [21,22] for the Navier Stokes equations has the better accuracy for pressure. © 2011 Elsevier Inc.

  17. An efficient numerical progressive diagonalization scheme for the quantum Rabi model revisited

    International Nuclear Information System (INIS)

    Pan, Feng; Bao, Lina; Dai, Lianrong; Draayer, Jerry P

    2017-01-01

    An efficient numerical progressive diagonalization scheme for the quantum Rabi model is revisited. The advantage of the scheme lies in the fact that the quantum Rabi model can be solved almost exactly by using the scheme that only involves a finite set of one variable polynomial equations. The scheme is especially efficient for a specified eigenstate of the model, for example, the ground state. Some low-lying level energies of the model for several sets of parameters are calculated, of which one set of the results is compared to that obtained from the Braak’s exact solution proposed recently. It is shown that the derivative of the entanglement measure defined in terms of the reduced von Neumann entropy with respect to the coupling parameter does reach the maximum near the critical point deduced from the classical limit of the Dicke model, which may provide a probe of the critical point of the crossover in finite quantum many-body systems, such as that in the quantum Rabi model. (paper)

  18. NSVZ scheme with the higher derivative regularization for N=1 SQED

    International Nuclear Information System (INIS)

    Kataev, A.L.; Stepanyantz, K.V.

    2013-01-01

    The exact NSVZ relation between a β-function of N=1 SQED and an anomalous dimension of the matter superfields is studied within the Slavnov higher derivative regularization approach. It is shown that if the renormalization group functions are defined in terms of the bare coupling constant, this relation is always valid. In the renormalized theory the NSVZ relation is obtained in the momentum subtraction scheme supplemented by a special finite renormalization. Unlike the dimensional reduction, the higher derivative regularization allows to fix this finite renormalization. This is made by imposing the conditions Z 3 (α,μ=Λ)=1 and Z(α,μ=Λ)=1 on the renormalization constants of N=1 SQED, where Λ is a parameter in the higher derivative term. The results are verified by the explicit three-loop calculation. In this approximation we relate the DR ¯ scheme and the NSVZ scheme defined within the higher derivative approach by the finite renormalization

  19. QPS upgrade and machine protection during LS1

    International Nuclear Information System (INIS)

    Denz, R.

    2012-01-01

    The presentation will explain all the proposed changes and discuss the impact on other shutdown activities. The upgrade of the LHC Quench Protection System QPS during LS1 with respect to radiation to electronics will concern the re-location of equipment and installation of new radiation tolerant hardware. The mid-term plan for further R2E upgrades will be addressed. The protection systems for insertion region magnets and inner triplets will be equipped with a dedicated bus-bar splice supervision including some additional modifications in order to improve the EMC immunity. The extension of the supervision capabilities of the QPS will concern the quench heater circuits, the earth voltage feelers and some tools to ease the system maintenance. The protection of the undulators will be revised in order to allow more transparent operation. The installation of snubber capacitors and arc chambers for the main quad circuits will complete the upgrade of the energy extraction systems. Finally the re-commissioning of the protection systems prior to the powering tests will be addressed. (author)

  20. LS1 Report: PS Booster prepares for beam

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    With Linac2 already up and running, the countdown to beam in the LHC has begun! The next in line is the PS Booster, which will close up shop to engineers early next week. The injector will be handed over to the Operations Group who are tasked with getting it ready for active duty.   Taken as we approach the end of LS1 activities, this image shows where protons will soon be injected from Linac2 into the four PS Booster rings. Over the coming two months, the Operations Group will be putting the Booster's new elements through their paces. "Because of the wide range of upgrades and repairs carried out in the Booster, we have a very full schedule of tests planned for the machine," says Bettina Mikulec, PS Booster Engineer in Charge. "We will begin with cold checks; these are a wide range of tests carried out without beam, including system tests with power on/off and with varying settings, as well as verification of the controls system and timings." Amon...

  1. Global land-atmosphere coupling associated with cold climate processes

    Science.gov (United States)

    Dutra, Emanuel

    This dissertation constitutes an assessment of the role of cold processes, associated with snow cover, in controlling the land-atmosphere coupling. The work was based on model simulations, including offline simulations with the land surface model HTESSEL, and coupled atmosphere simulations with the EC-EARTH climate model. A revised snow scheme was developed and tested in HTESSEL and EC-EARTH. The snow scheme is currently operational at the European Centre for Medium-Range Weather Forecasts integrated forecast system, and in the default configuration of EC-EARTH. The improved representation of the snowpack dynamics in HTESSEL resulted in improvements in the near surface temperature simulations of EC-EARTH. The new snow scheme development was complemented with the option of multi-layer version that showed its potential in modeling thick snowpacks. A key process was the snow thermal insulation that led to significant improvements of the surface water and energy balance components. Similar findings were observed when coupling the snow scheme to lake ice, where lake ice duration was significantly improved. An assessment on the snow cover sensitivity to horizontal resolution, parameterizations and atmospheric forcing within HTESSEL highlighted the role of the atmospheric forcing accuracy and snowpack parameterizations in detriment of horizontal resolution over flat regions. A set of experiments with and without free snow evolution was carried out with EC-EARTH to assess the impact of the interannual variability of snow cover on near surface and soil temperatures. It was found that snow cover interannual variability explained up to 60% of the total interannual variability of near surface temperature over snow covered regions. Although these findings are model dependent, the results showed consistency with previously published work. Furthermore, the detailed validation of the snow dynamics simulations in HTESSEL and EC-EARTH guarantees consistency of the results.

  2. Challenges in coupled thermal-hydraulics and neutronics simulations for LWR safety analysis

    International Nuclear Information System (INIS)

    Ivanov, Kostadin; Avramova, Maria

    2007-01-01

    The simulation of nuclear power plant accident conditions requires three-dimensional (3D) modeling of the reactor core to ensure a realistic description of physical phenomena. The operational flexibility of Light Water Reactor (LWR) plants can be improved by utilizing accurate 3D coupled neutronics/thermal-hydraulics calculations for safety margins evaluations. There are certain requirements to the coupling of thermal-hydraulic system codes and neutron-kinetics codes that ought to be considered. The objective of these requirements is to provide accurate solutions in a reasonable amount of CPU time in coupled simulations of detailed operational transient and accident scenarios. These requirements are met by the development and implementation of six basic components of the coupling methodologies: ways of coupling (internal or external coupling); coupling approach (integration algorithm or parallel processing); spatial mesh overlays; coupled time-step algorithms; coupling numerics (explicit, semi-implicit and implicit schemes); and coupled convergence schemes. These principles of the coupled simulations are discussed in details along with the scientific issues associated with the development of appropriate neutron cross-section libraries for coupled code transient modeling. The current trends in LWR nuclear power generation and regulation as well as the design of next generation LWR reactor concepts along with the continuing computer technology progress stimulate further development of these coupled code systems. These efforts have been focused towards extending the analysis capabilities as well as refining the scale and level of detail of the coupling. This article analyses the coupled phenomena and modeling challenges on both global (assembly-wise) and local (pin-wise) levels. The issues related to the consistent qualification of coupled code systems as well as their application to different types of LWR transients are presented. Finally, the advances in numerical

  3. Safety and pharmacokinetics of the Fc-modified HIV-1 human monoclonal antibody VRC01LS: A Phase 1 open-label clinical trial in healthy adults.

    Directory of Open Access Journals (Sweden)

    Martin R Gaudinski

    2018-01-01

    Full Text Available VRC01 is a human broadly neutralizing monoclonal antibody (bnMAb against the CD4-binding site of the HIV-1 envelope glycoprotein (Env that is currently being evaluated in a Phase IIb adult HIV-1 prevention efficacy trial. VRC01LS is a modified version of VRC01, designed for extended serum half-life by increased binding affinity to the neonatal Fc receptor.This Phase I dose-escalation study of VRC01LS in HIV-negative healthy adults was conducted by the Vaccine Research Center (VRC at the National Institutes of Health (NIH Clinical Center (Bethesda, MD. The age range of the study volunteers was 21-50 years; 51% of study volunteers were male and 49% were female. Primary objectives were safety and tolerability of VRC01LS intravenous (IV infusions at 5, 20, and 40 mg/kg infused once, 20 mg/kg given three times at 12-week intervals, and subcutaneous (SC delivery at 5 mg/kg delivered once, or three times at 12-week intervals. Secondary objectives were pharmacokinetics (PK, serum neutralization activity, and development of antidrug antibodies. Enrollment began on November 16, 2015, and concluded on August 23, 2017. This report describes the safety data for the first 37 volunteers who received administrations of VRC01LS. There were no serious adverse events (SAEs or dose-limiting toxicities. Mild malaise and myalgia were the most common adverse events (AEs. There were six AEs assessed as possibly related to VRC01LS administration, and all were mild in severity and resolved during the study. PK data were modeled based on the first dose of VRC01LS in the first 25 volunteers to complete their schedule of evaluations. The mean (±SD serum concentration 12 weeks after one IV administration of 20 mg/kg or 40 mg/kg were 180 ± 43 μg/mL (n = 7 and 326 ± 35 μg/mL (n = 5, respectively. The mean (±SD serum concentration 12 weeks after one IV and SC administration of 5 mg/kg were 40 ± 3 μg/mL (n = 2 and 25 ± 5 μg/mL (n = 9, respectively. Over the 5-40 mg

  4. Adaptive Tuning of Frequency Thresholds Using Voltage Drop Data in Decentralized Load Shedding

    DEFF Research Database (Denmark)

    Hoseinzadeh, Bakhtyar; Faria Da Silva, Filipe Miguel; Bak, Claus Leth

    2015-01-01

    Load shedding (LS) is the last firewall and the most expensive control action against power system blackout. In the conventional under frequency LS (UFLS) schemes, the load drop locations are already determined independently of the event location. Furthermore, the frequency thresholds of LS relays...... are prespecified and constant values which may not be a comprehensive solution for widespread range of possible events. This paper addresses the decentralized LS in which the instantaneous voltage deviation of load buses is used to determine the frequency thresholds of LS relays. The higher frequency thresholds...

  5. META-ANALISI E APPLICAZIONE DI UNA PROPOSTA DIDATTICA ORIENTATA ALL’AZIONE PER L’APPRENDIMENTO DEI SEGNALI DISCORSIVI IN ITALIANO LS

    Directory of Open Access Journals (Sweden)

    Roberta Ferroni

    2016-09-01

    Full Text Available Nel presente contributo si riportano i risultati di uno studio i cui obiettivi sono: a verificare come vengono trattati i segnali discorsivi (SD in un manuale di italiano LS il cui approccio è orientato all’azione; b analizzare come questi SD vengono percepiti e ritualizzati nel parlato dialogico di studenti di italiano LS di livello B1 del Quadro comune europeo di riferimento per le lingue. La ricerca è stata svolta fra studenti universitari del corso di Laurea di Lingua e Letteratura Italiana della Facoltà di Filosofia, Lettere e Scienze Umane dell’Università di San Paolo del Brasile. Dall’analisi delle proposte didattiche, tratte dall’unità 6 del corso d’italiano per stranieri Bravissimo! 3-B1(Birello e Vilagrasa, 2014, si evince che le attività incentrate sui SD presuppongono un costante reimpiego in un contesto di lavoro significativo, attraverso degli «spazi interattivi» in cui gli apprendenti prendono consapevolezza e mettono alla prova le regole che gestiscono la co-costruzione conversazionale in LS. L’esposizione e la riflessione sui SD, abbinate a proposte di attività interattive significative, in cui lo studente ha un preciso scopo da raggiungere, offrono delle opportunità di riutilizzo dei SD simile a quello che può prodursi in una situazione al di fuori dell’aula. Meta-analysis and application for action-learning italian fl discourse signals In this paper we report the results of a study whose objectives were: a to determine how discourse markers (DMs are addressed in an action-oriented Italian FL textbooks; b to analyze how these DMs are perceived and ritualized in the spoken conversation of students studying Italian as a FL at the B1 level as defined by the Common European Framework of Reference for Languages. The study was carried out among university students majoring in Italian Language and Literature at the School of Philosophy, Letters and Humanities of the University of São Paulo, Brazil

  6. Optical coupling structure made by imprinting between single-mode polymer waveguide and embedded VCSEL

    NARCIS (Netherlands)

    Karppinen, M.; Salminen, N.; Korhonen, T.; Alajoki, T.; Petäjä, J.; Bosman, E.; Steenberge, G. van; Justice, J.; Khan, U.; Corbett, B.; Boersma, A.

    2015-01-01

    Polymer-based integrated optics is attractive for inter-chip optical interconnection applications, for instance, for coupling photonic devices to fibers in high density packaging. In such a hybrid integration scheme, a key challenge is to achieve efficient optical coupling between the photonic chips

  7. Hour time-scale QPOs in the X-ray and radio emission of LS I +61°303

    Science.gov (United States)

    Nösel, S.; Sharma, R.; Massi, M.; Cimò, G.; Chernyakova, M.

    2018-05-01

    LS I +61°303 is an X-ray binary with a radio outburst every ˜27 d. Previous studies of the stellar system revealed radio microflares superimposed on the large radio outburst. We present here new radio observations of LS I +61°303 at 2.2 GHz with the Westerbork Synthesis Radio Telescope (WSRT). Using various timing analysis methods, we find significant quasi-periodic oscillations (QPOs) of 55 min stable over the duration of 4 d. We also use archival data obtained from the Suzaku satellite at X-ray wavelengths. We report here for the first time significant X-ray QPOs of about 2 h present over the time span of 21 h. We compare our results with the previously reported QPO observations and we conclude that the QPOs seem to be associated with the radio outburst, independent of the amplitude of the outburst. Finally, the different QPO time-scales are discussed in the context of magnetic reconnection.

  8. Review of multi-physics temporal coupling methods for analysis of nuclear reactors

    International Nuclear Information System (INIS)

    Zerkak, Omar; Kozlowski, Tomasz; Gajev, Ivan

    2015-01-01

    Highlights: • Review of the numerical methods used for the multi-physics temporal coupling. • Review of high-order improvements to the Operator Splitting coupling method. • Analysis of truncation error due to the temporal coupling. • Recommendations on best-practice approaches for multi-physics temporal coupling. - Abstract: The advanced numerical simulation of a realistic physical system typically involves multi-physics problem. For example, analysis of a LWR core involves the intricate simulation of neutron production and transport, heat transfer throughout the structures of the system and the flowing, possibly two-phase, coolant. Such analysis involves the dynamic coupling of multiple simulation codes, each one devoted to the solving of one of the coupled physics. Multiple temporal coupling methods exist, yet the accuracy of such coupling is generally driven by the least accurate numerical scheme. The goal of this paper is to review in detail the approaches and numerical methods that can be used for the multi-physics temporal coupling, including a comprehensive discussion of the issues associated with the temporal coupling, and define approaches that can be used to perform multi-physics analysis. The paper is not limited to any particular multi-physics process or situation, but is intended to provide a generic description of multi-physics temporal coupling schemes for any development stage of the individual (single-physics) tools and methods. This includes a wide spectrum of situation, where the individual (single-physics) solvers are based on pre-existing computation codes embedded as individual components, or a new development where the temporal coupling can be developed and implemented as a part of code development. The discussed coupling methods are demonstrated in the framework of LWR core analysis

  9. Coupling an optical trap to a mass separator

    Energy Technology Data Exchange (ETDEWEB)

    Chamberlin, E.P.; Sandberg, V.D.; Tupa, D.; Vieira, D.J.; Zhao, X.X. [Los Alamos National Lab., NM (United States); Guckert, R.; Wollnik, H. [Los Alamos National Lab., NM (United States)]/[Giessen Univ. (Germany); Preston, D.W. [Los Alamos National Lab., NM (United States)]/[California State Univ., Hayward, CA (United States)

    1996-12-31

    The efficient coupling of a magneto-optical trap to a mass separator is being developed to undertake high-precision electroweak interaction measurements in a series of radioisotopes. The use of ion implantation and subsequent heated-foil release is being pursued as a suitable way of introducing radioactive samples into the ultrahigh vacuum region of an optical trap without gas loading. This paper discusses the layout of the mass separator,the coupling to a magneto- optical trap, and the implantation and release scheme.

  10. Coupling an optical trap to a mass separator

    International Nuclear Information System (INIS)

    Chamberlin, E.P.; Sandberg, V.D.; Tupa, D.; Vieira, D.J.; Zhao, X.X.; Guckert, R.; Wollnik, H.; Preston, D.W.

    1996-01-01

    The efficient coupling of a magneto-optical trap to a mass separator is being developed to undertake high-precision electroweak interaction measurements in a series of radioisotopes. The use of ion implantation and subsequent heated-foil release is being pursued as a suitable way of introducing radioactive samples into the ultrahigh vacuum region of an optical trap without gas loading. This paper discusses the layout of the mass separator,the coupling to a magneto- optical trap, and the implantation and release scheme

  11. Fuzzy Pruning Based LS-SVM Modeling Development for a Fermentation Process

    Directory of Open Access Journals (Sweden)

    Weili Xiong

    2014-01-01

    Full Text Available Due to the complexity and uncertainty of microbial fermentation processes, data coming from the plants often contain some outliers. However, these data may be treated as the normal support vectors, which always deteriorate the performance of soft sensor modeling. Since the outliers also contaminate the correlation structure of the least square support vector machine (LS-SVM, the fuzzy pruning method is provided to deal with the problem. Furthermore, by assigning different fuzzy membership scores to data samples, the sensitivity of the model to the outliers can be reduced greatly. The effectiveness and efficiency of the proposed approach are demonstrated through two numerical examples as well as a simulator case of penicillin fermentation process.

  12. Scheme for Quantum Computing Immune to Decoherence

    Science.gov (United States)

    Williams, Colin; Vatan, Farrokh

    2008-01-01

    that the derivation provides explicit constructions for finding the exchange couplings in the physical basis needed to implement any arbitrary 1-qubit gate. These constructions lead to spintronic encodings of quantum logic that are more efficient than those of a previously published scheme that utilizes a universal but fixed set of gates.

  13. Studies of the plasma droplet accelerator scheme

    International Nuclear Information System (INIS)

    Mori, W.B.; Joshi, C.; Dawson, J.M.; Lee, K.; Forslund, D.W.; Kindel, J.M.

    1985-01-01

    In the plasma droplet accelerator scheme, proposed by R. Palmer, a sequence of liquid micro-spheres generated by a jet printer are ionized by an incoming intense laser. The hope is that the micro-spheres now acting as conducting balls will allow efficient coupling of the incoming laser radiation into an accelerating mode. Motivated by this the authors have carried out 2D, particle simulations in order to answer some of the plasma physics questions hitherto unaddressed. In particular they find that at least for laser intensities exceeding v 0 /c=0.03 (/sup ∼/10 13 w/cm 2 for a CO 2 laser), the incident laser light is rather efficiently absorbed in a hot electron distribution. Up to 70% of the incident energy can be absorbed by these electrons which rapidly expand and fill the vacuum space between the microspheres with a low density plasma. These results indicate that it is advisable to stay clear of plasma formation and thus put on an upper limit on the maximum surface fields that can be tolerated in the droplet-accelerator scheme

  14. Studies of the plasma droplet accelerator scheme

    International Nuclear Information System (INIS)

    Mori, W.B.; Dawson, J.M.; Forslund, D.W.; Joshi, C.; Kindel, J.M.; Lee, K.

    1985-01-01

    In the plasma droplet accelerator scheme, proposed by R. Palmer, a sequence of liquid micro-spheres generated by a jet printer are ionized by an incoming intense laser. The hope is that the micro-spheres now acting as conducting balls will allow efficient coupling of the incoming laser radiation into an accelerating mode. Motivated by this we have carried out 2D, particle simulations in order to answer some of the plasma physics questions hitherto unaddressed. In particular we find that at least for laser intensities exceeding v /SUB o/ /c=0.03 ( about10 13 w/cm 2 for a CO 2 laser), the incident laser light is rather efficiently absorbed in a hot electron distribution. Up to 70% of the incident energy can be absorbed by these electrons which rapidly expand and fill the vacuum space between the microspheres with a low density plasma. These results indicate that it is advisable to stay clear of plasma formation and thus put on an upper limit on the maximum surface fields that can be tolerated in the droplet-accelerator scheme

  15. Anticipating and projective-anticipating synchronization of coupled multidelay feedback systems

    International Nuclear Information System (INIS)

    Hoang, Thang Manh; Nakagawa, Masahiro

    2007-01-01

    In this Letter, the model of coupled multidelay feedback systems is investigated with the schemes of anticipating and projective-anticipating synchronizations. Under these synchronization schemes, the slave anticipates the master's trajectory. Moreover, with projective-anticipating synchronization there exists a scale factor in the amplitudes of the master's and slave's state variables. In the both cases, the driving signals are in the form of multiple nonlinear transformations of delayed state variable. The Krasovskii-Lyapunov theory is used to consider the sufficient condition for synchronization. The effectiveness of the proposed schemes is confirmed by the numerical simulation of specific examples with modified Ikeda and Mackey-Glass systems

  16. Diagnosis of transverse coupling errors in a storage ring

    International Nuclear Information System (INIS)

    Bagley, P.; Rubin, D.

    1987-01-01

    In a coupled lattice excitation of either one of the two transverse normal modes will generally excite both horizontal and vertical motion at an observation point. A measurement of the relative phase and amplitude of the two components permits a partial reconstruction of the off-diagonal elements of the full turn transfer matrix. At each of the nearly 100 beam position detectors in CESR the coupled transfer matrices are measured. A fit of plausible sources of coupling to the data can improve our understanding of lattice errors and permit an optimization of the rotated quad, solenoid compensation scheme

  17. Exact analysis of Packet Reversed Packet Combining Scheme and Modified Packet Combining Scheme; and a combined scheme

    International Nuclear Information System (INIS)

    Bhunia, C.T.

    2007-07-01

    Packet combining scheme is a well defined simple error correction scheme for the detection and correction of errors at the receiver. Although it permits a higher throughput when compared to other basic ARQ protocols, packet combining (PC) scheme fails to correct errors when errors occur in the same bit locations of copies. In a previous work, a scheme known as Packet Reversed Packet Combining (PRPC) Scheme that will correct errors which occur at the same bit location of erroneous copies, was studied however PRPC does not handle a situation where a packet has more than 1 error bit. The Modified Packet Combining (MPC) Scheme that can correct double or higher bit errors was studied elsewhere. Both PRPC and MPC schemes are believed to offer higher throughput in previous studies, however neither adequate investigation nor exact analysis was done to substantiate this claim of higher throughput. In this work, an exact analysis of both PRPC and MPC is carried out and the results reported. A combined protocol (PRPC and MPC) is proposed and the analysis shows that it is capable of offering even higher throughput and better error correction capability at high bit error rate (BER) and larger packet size. (author)

  18. A range of formulations to couple mass and momentum equations

    International Nuclear Information System (INIS)

    Darbandi, M.; Schneider, G.E.

    2002-01-01

    Since the innovation of control-volume-based methods, the issue of pressure-velocity decoupling has prompted the researcher to develop and employ staggered grid arrangement. The difficulties and disadvantages of staggered-grid-based schemes have encouraged the workers to investigate more in alternative scheme, i.e., the collocated-grid-based scheme. The primitive idea in collocated scheme is to couple the mass and momentum equations with the help of two types of velocity definitions instead of two types of grid arrangements. Following the work of preceding workers, we introduce a general strategy which enables the workers to develop a wide range of velocity definitions which can be properly used in collocated formulations. The developed formulations are then tested in a domain with source and sink. The results of the extended formulations are eventually discussed. (author)

  19. Waveguide-loaded silica fibers for coupling to high-index micro-resonators

    Science.gov (United States)

    Latawiec, P.; Burek, M. J.; Venkataraman, V.; Lončar, M.

    2016-01-01

    Tapered silica fibers are often used to rapidly probe the optical properties of micro-resonators. However, their low refractive index precludes phase-matching when coupling to high-index micro-resonators, reducing efficiency. Here, we demonstrate efficient optical coupling from tapered fibers to high-index micro-resonators by loading the fibers with an ancillary adiabatic waveguide-coupler fabricated via angled-etching. We demonstrate greatly enhanced coupling to a silicon multimode micro-resonator when compared to coupling via the bare fiber only. Signatures of resonator optical bistability are observed at high powers. This scheme can be applied to resonators of any size and material, increasing the functional scope of fiber coupling.

  20. Analytical solution to the coupled evolution of multidimensional NMR data

    International Nuclear Information System (INIS)

    Mueller, Geoffrey A.

    2009-01-01

    A substantial time savings in the collection of multidimensional NMR data can be achieved by coupling the evolution of nuclei in the indirect dimensions. In order to save time, the sampling of the indirect dimensions is inherently incomplete. Therefore, many algorithms and samplings schemes have been developed aimed at separating the coevolved frequencies into analyzable data with limited artifacts. This paper extends the use of circulant matrices to describe coupled evolution with convolutions. By understanding the data in terms of convolutions, there is an exact solution to the inversion problem of extracting the orthogonal vectors from the coupled dimensions. Previously, this inversion problem has been solved using peak coordinates extracted from spectra. In contrast, the method described here uses spectra directly. This solution suggests a simple sampling scheme of collecting N orthogonal spectra, and N + 1 projections at specific projection angles, however, the theory developed can be extended generally to arbitrary projection angles. The circulant matrix methodology is demonstrated for simulated and real data. Further, an algorithm for separating overlapped signals in the detected dimension is presented. The algorithm involves the forward calculation of the coupled spectra from the orthogonal spectra, followed by back calculation of the orthogonal spectra from the coupled spectra, thus permitting rigorous cross-validation. This algorithm is shown to be robust in that erroneous solutions give rise to large artifacts

  1. R2E strategy and activities during LS1

    International Nuclear Information System (INIS)

    Perrot, A.L.

    2012-01-01

    The level of the flux of hadrons with energy in the multi MeV range expected from the collimation system at Point 7 and from the collisions at the interaction Points 1, 5 and 8 will induce Single Event Errors (SEEs) of the standard electronics present in the equipment located around these Points. Such events would perturb LHC operation. As a consequence, within the framework of the R2E (Radiation to Electronics) Mitigation Project, the sensitive equipment will be shielded or relocated to safer areas. These mitigation activities will be performed mainly during Long Shutdown 1 (LS1). About 15 groups (including equipment owners) will be involved in these activities with work periods from a few days to several months. Some of them will have to work in parallel in several LHC points. This document presents these mitigation activities with their associated planning, organization process, and main concerns as identified today. (author)

  2. First-Principle Characterization for Singlet Fission Couplings.

    Science.gov (United States)

    Yang, Chou-Hsun; Hsu, Chao-Ping

    2015-05-21

    The electronic coupling for singlet fission, an important parameter for determining the rate, has been found to be too small unless charge-transfer (CT) components were introduced in the diabatic states, mostly through perturbation or a model Hamiltonian. In the present work, the fragment spin difference (FSD) scheme was generalized to calculate the singlet fission coupling. The largest coupling strength obtained was 14.8 meV for two pentacenes in a crystal structure, or 33.7 meV for a transition-state structure, which yielded a singlet fission lifetime of 239 or 37 fs, generally consistent with experimental results (80 fs). Test results with other polyacene molecules are similar. We found that the charge on one fragment in the S1 diabatic state correlates well with FSD coupling, indicating the importance of the CT component. The FSD approach is a useful first-principle method for singlet fission coupling, without the need to include the CT component explicitly.

  3. The effect and correction of coupling generated by the RHIC triplet quadrupoles

    International Nuclear Information System (INIS)

    Pilat, F.; Peggs, S.; Tepikian, S.; Trbojevic, D.; Wei, J.

    1995-01-01

    This study explores the possibility of operating the nominal RHIC coupling correction system in local decoupling mode, where a subset of skew quadrupoles are independently set by minimizing the coupling as locally measured by beam position monitors. The goal is to establish a correction procedure for the skew quadrupole errors in the interaction region triplets that does not rely on a priori knowledge of the individual errors. After a description of the present coupling correction scheme envisioned for RHIC, the basics of the local decoupling method will be briefly recalled in the context of its implementation in the TEAPOT simulation code as well as operationally. The method is then applied to the RHIC lattice: a series of simple tests establish that single triplet skew quadrupole errors can be corrected by local decoupling. More realistic correction schemes are then studied in order to correct distributed sources of skew quadrupole errors: the machine can be decoupled either by pure local decoupling or by a combination of global (minimum tune separation) and local decoupling. The different correction schemes are successively validated and evaluated by standard RHIC simulation runs with the complete set of errors and corrections. The different solutions and results are finally discussed together with their implications for the hardware

  4. Global land-atmosphere coupling associated with cold climate processes

    OpenAIRE

    Dutra, Emanuel, 1983-

    2011-01-01

    Tese de doutoramento, Ciências Geofísicas e da Geoinformação (Meteorologia), Universidade de Lisboa, Faculdade de Ciências, 2011 This dissertation constitutes an assessment of the role of cold processes, associated with snow cover, in controlling the land-atmosphere coupling. The work was based on model simulations, including offline simulations with the land surface model HTESSEL, and coupled atmosphere simulations with the EC-EARTH climate model. A revised snow scheme was developed and t...

  5. Hamiltonian structure of the integrable coupling of the Jaulent-Miodek hierarchy

    International Nuclear Information System (INIS)

    Zhang, Yufeng; Fan, Engui

    2006-01-01

    A scheme for deducing Hamiltonian structures of the higher-dimensional hierarchies of evolution equations is presented which is devoting to obtaining the Hamiltonian structures of integrable coupling of the Jaulent-Miodek hierarchy

  6. Spatially coupled LDPC coding in cooperative wireless networks

    NARCIS (Netherlands)

    Jayakody, D.N.K.; Skachek, V.; Chen, B.

    2016-01-01

    This paper proposes a novel technique of spatially coupled low-density parity-check (SC-LDPC) code-based soft forwarding relaying scheme for a two-way relay system. We introduce an array-based optimized SC-LDPC codes in relay channels. A more precise model is proposed to characterize the residual

  7. Extending the reach of strong-coupling: an iterative technique for Hamiltonian lattice models

    International Nuclear Information System (INIS)

    Alberty, J.; Greensite, J.; Patkos, A.

    1983-12-01

    The authors propose an iterative method for doing lattice strong-coupling-like calculations in a range of medium to weak couplings. The method is a modified Lanczos scheme, with greatly improved convergence properties. The technique is tested on the Mathieu equation and on a Hamiltonian finite-chain XY model, with excellent results. (Auth.)

  8. Optimised Iteration in Coupled Monte Carlo - Thermal-Hydraulics Calculations

    Science.gov (United States)

    Hoogenboom, J. Eduard; Dufek, Jan

    2014-06-01

    This paper describes an optimised iteration scheme for the number of neutron histories and the relaxation factor in successive iterations of coupled Monte Carlo and thermal-hydraulic reactor calculations based on the stochastic iteration method. The scheme results in an increasing number of neutron histories for the Monte Carlo calculation in successive iteration steps and a decreasing relaxation factor for the spatial power distribution to be used as input to the thermal-hydraulics calculation. The theoretical basis is discussed in detail and practical consequences of the scheme are shown, among which a nearly linear increase per iteration of the number of cycles in the Monte Carlo calculation. The scheme is demonstrated for a full PWR type fuel assembly. Results are shown for the axial power distribution during several iteration steps. A few alternative iteration method are also tested and it is concluded that the presented iteration method is near optimal.

  9. Optimized iteration in coupled Monte-Carlo - Thermal-hydraulics calculations

    International Nuclear Information System (INIS)

    Hoogenboom, J.E.; Dufek, J.

    2013-01-01

    This paper describes an optimised iteration scheme for the number of neutron histories and the relaxation factor in successive iterations of coupled Monte Carlo and thermal-hydraulic reactor calculations based on the stochastic iteration method. The scheme results in an increasing number of neutron histories for the Monte Carlo calculation in successive iteration steps and a decreasing relaxation factor for the spatial power distribution to be used as input to the thermal-hydraulics calculation. The theoretical basis is discussed in detail and practical consequences of the scheme are shown, among which a nearly linear increase per iteration of the number of cycles in the Monte Carlo calculation. The scheme is demonstrated for a full PWR type fuel assembly. Results are shown for the axial power distribution during several iteration steps. A few alternative iteration methods are also tested and it is concluded that the presented iteration method is near optimal. (authors)

  10. Association schemes perspective of microbubble cluster in ultrasonic fields.

    Science.gov (United States)

    Behnia, S; Yahyavi, M; Habibpourbisafar, R

    2018-06-01

    Dynamics of a cluster of chaotic oscillators on a network are studied using coupled maps. By introducing the association schemes, we obtain coupling strength in the adjacency matrices form, which satisfies Markov matrices property. We remark that in general, the stability region of the cluster of oscillators at the synchronization state is characterized by Lyapunov exponent which can be defined based on the N-coupled map. As a detailed physical example, dynamics of microbubble cluster in an ultrasonic field are studied using coupled maps. Microbubble cluster dynamics have an indicative highly active nonlinear phenomenon, were not easy to be explained. In this paper, a cluster of microbubbles with a thin elastic shell based on the modified Keller-Herring equation in an ultrasonic field is demonstrated in the framework of the globally coupled map. On the other hand, a relation between the microbubble elements is replaced by a relation between the vertices. Based on this method, the stability region of microbubbles pulsations at complete synchronization state has been obtained analytically. In this way, distances between microbubbles as coupling strength play the crucial role. In the stability region, we thus observe that the problem of study of dynamics of N-microbubble oscillators reduce to that of a single microbubble. Therefore, the important parameters of the isolated microbubble such as applied pressure, driving frequency and the initial radius have effective behavior on the synchronization state. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Synchronization of coupled metronomes on two layers

    Science.gov (United States)

    Zhang, Jing; Yu, Yi-Zhen; Wang, Xin-Gang

    2017-12-01

    Coupled metronomes serve as a paradigmatic model for exploring the collective behaviors of complex dynamical systems, as well as a classical setup for classroom demonstrations of synchronization phenomena. Whereas previous studies of metronome synchronization have been concentrating on symmetric coupling schemes, here we consider the asymmetric case by adopting the scheme of layered metronomes. Specifically, we place two metronomes on each layer, and couple two layers by placing one on top of the other. By varying the initial conditions of the metronomes and adjusting the friction between the two layers, a variety of synchronous patterns are observed in experiment, including the splay synchronization (SS) state, the generalized splay synchronization (GSS) state, the anti-phase synchronization (APS) state, the in-phase delay synchronization (IPDS) state, and the in-phase synchronization (IPS) state. In particular, the IPDS state, in which the metronomes on each layer are synchronized in phase but are of a constant phase delay to metronomes on the other layer, is observed for the first time. In addition, a new technique based on audio signals is proposed for pattern detection, which is more convenient and easier to apply than the existing acquisition techniques. Furthermore, a theoretical model is developed to explain the experimental observations, and is employed to explore the dynamical properties of the patterns, including the basin distributions and the pattern transitions. Our study sheds new lights on the collective behaviors of coupled metronomes, and the developed setup can be used in the classroom for demonstration purposes.

  12. A multi-scale computational scheme for anisotropic hydro-mechanical couplings in saturated heterogeneous porous media

    NARCIS (Netherlands)

    Mercatoris, B.C.N.; Massart, T.J.; Sluys, L.J.

    2013-01-01

    This contribution discusses a coupled two-scale framework for hydro-mechanical problems in saturated heterogeneous porous geomaterials. The heterogeneous nature of such materials can lead to an anisotropy of the hydro-mechanical couplings and non-linear effects. Based on an assumed model of the

  13. Assessment of Planetary-Boundary-Layer Schemes in the Weather Research and Forecasting Model Within and Above an Urban Canopy Layer

    Science.gov (United States)

    Ferrero, Enrico; Alessandrini, Stefano; Vandenberghe, Francois

    2018-03-01

    We tested several planetary-boundary-layer (PBL) schemes available in the Weather Research and Forecasting (WRF) model against measured wind speed and direction, temperature and turbulent kinetic energy (TKE) at three levels (5, 9, 25 m). The Urban Turbulence Project dataset, gathered from the outskirts of Turin, Italy and used for the comparison, provides measurements made by sonic anemometers for more than 1 year. In contrast to other similar studies, which have mainly focused on short-time periods, we considered 2 months of measurements (January and July) representing both the seasonal and the daily variabilities. To understand how the WRF-model PBL schemes perform in an urban environment, often characterized by low wind-speed conditions, we first compared six PBL schemes against observations taken by the highest anemometer located in the inertial sub-layer. The availability of the TKE measurements allows us to directly evaluate the performances of the model; results of the model evaluation are presented in terms of quantile versus quantile plots and statistical indices. Secondly, we considered WRF-model PBL schemes that can be coupled to the urban-surface exchange parametrizations and compared the simulation results with measurements from the two lower anemometers located inside the canopy layer. We find that the PBL schemes accounting for TKE are more accurate and the model representation of the roughness sub-layer improves when the urban model is coupled to each PBL scheme.

  14. A gene encoding an abscisic acid biosynthetic enzyme (LsNCED4) collocates with the high temperature germination locus Htg6.1 in lettuce (Lactuca sp.).

    Science.gov (United States)

    Argyris, Jason; Truco, María José; Ochoa, Oswaldo; McHale, Leah; Dahal, Peetambar; Van Deynze, Allen; Michelmore, Richard W; Bradford, Kent J

    2011-01-01

    Thermoinhibition, or failure of seeds to germinate when imbibed at warm temperatures, can be a significant problem in lettuce (Lactuca sativa L.) production. The reliability of stand establishment would be improved by increasing the ability of lettuce seeds to germinate at high temperatures. Genes encoding germination- or dormancy-related proteins were mapped in a recombinant inbred line population derived from a cross between L. sativa cv. Salinas and L. serriola accession UC96US23. This revealed several candidate genes that are located in the genomic regions containing quantitative trait loci (QTLs) associated with temperature and light requirements for germination. In particular, LsNCED4, a temperature-regulated gene in the biosynthetic pathway for abscisic acid (ABA), a germination inhibitor, mapped to the center of a previously detected QTL for high temperature germination (Htg6.1) from UC96US23. Three sets of sister BC(3)S(2) near-isogenic lines (NILs) that were homozygous for the UC96US23 allele of LsNCED4 at Htg6.1 were developed by backcrossing to cv. Salinas and marker-assisted selection followed by selfing. The maximum temperature for germination of NIL seed lots with the UC96US23 allele at LsNCED4 was increased by 2-3°C when compared with sister NIL seed lots lacking the introgression. In addition, the expression of LsNCED4 was two- to threefold lower in the former NIL lines as compared to expression in the latter. Together, these data strongly implicate LsNCED4 as the candidate gene responsible for the Htg6.1 phenotype and indicate that decreased ABA biosynthesis at high imbibition temperatures is a major factor responsible for the increased germination thermotolerance of UC96US23 seeds.

  15. Comparison of GCM subgrid fluxes calculated using BATS and SiB schemes with a coupled land-atmosphere high-resolution model

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Jinmei; Arritt, R.W. [Iowa State Univ., Ames, IA (United States)

    1996-12-31

    The importance of land-atmosphere interactions and biosphere in climate change studies has long been recognized, and several land-atmosphere interaction schemes have been developed. Among these, the Simple Biosphere scheme (SiB) of Sellers et al. and the Biosphere Atmosphere Transfer Scheme (BATS) of Dickinson et al. are two of the most widely known. The effects of GCM subgrid-scale inhomogeneities of surface properties in general circulation models also has received increasing attention in recent years. However, due to the complexity of land surface processes and the difficulty to prescribe the large number of parameters that determine atmospheric and soil interactions with vegetation, many previous studies and results seem to be contradictory. A GCM grid element typically represents an area of 10{sup 4}-10{sup 6} km{sup 2}. Within such an area, there exist variations of soil type, soil wetness, vegetation type, vegetation density and topography, as well as urban areas and water bodies. In this paper, we incorporate both BATS and SiB2 land surface process schemes into a nonhydrostatic, compressible version of AMBLE model (Atmospheric Model -- Boundary-Layer Emphasis), and compare the surface heat fluxes and mesoscale circulations calculated using the two schemes. 8 refs., 5 figs.

  16. Detecting the chirality for coupled quantum dots

    International Nuclear Information System (INIS)

    Cao Huijuan; Hu Lian

    2008-01-01

    We propose a scheme to detect the chirality for a system consisting of three coupled quantum dots. The chirality is found to be determined by the frequency of the transition between chiral states under the chiral symmetry broken perturbation. The results are important to construct quantum gates and to demonstrate chiral entangle states in the triangle spin dots

  17. Finite Boltzmann schemes

    NARCIS (Netherlands)

    Sman, van der R.G.M.

    2006-01-01

    In the special case of relaxation parameter = 1 lattice Boltzmann schemes for (convection) diffusion and fluid flow are equivalent to finite difference/volume (FD) schemes, and are thus coined finite Boltzmann (FB) schemes. We show that the equivalence is inherent to the homology of the

  18. Seniority zero pair coupled cluster doubles theory

    International Nuclear Information System (INIS)

    Stein, Tamar; Henderson, Thomas M.; Scuseria, Gustavo E.

    2014-01-01

    Coupled cluster theory with single and double excitations accurately describes weak electron correlation but is known to fail in cases of strong static correlation. Fascinatingly, however, pair coupled cluster doubles (p-CCD), a simplified version of the theory limited to pair excitations that preserve the seniority of the reference determinant (i.e., the number of unpaired electrons), has mean field computational cost and is an excellent approximation to the full configuration interaction (FCI) of the paired space provided that the orbital basis defining the pairing scheme is adequately optimized. In previous work, we have shown that optimization of the pairing scheme in the seniority zero FCI leads to a very accurate description of static correlation. The same conclusion extends to p-CCD if the orbitals are optimized to make the p-CCD energy stationary. We here demonstrate these results with numerous examples. We also explore the contributions of different seniority sectors to the coupled cluster doubles (CCD) correlation energy using different orbital bases. We consider both Hartree-Fock and Brueckner orbitals, and the role of orbital localization. We show how one can pair the orbitals so that the role of the Brueckner orbitals at the CCD level is retained at the p-CCD level. Moreover, we explore ways of extending CCD to accurately describe strongly correlated systems

  19. A direct Primitive Variable Recovery Scheme for hyperbolic conservative equations: The case of relativistic hydrodynamics.

    Science.gov (United States)

    Aguayo-Ortiz, A; Mendoza, S; Olvera, D

    2018-01-01

    In this article we develop a Primitive Variable Recovery Scheme (PVRS) to solve any system of coupled differential conservative equations. This method obtains directly the primitive variables applying the chain rule to the time term of the conservative equations. With this, a traditional finite volume method for the flux is applied in order avoid violation of both, the entropy and "Rankine-Hugoniot" jump conditions. The time evolution is then computed using a forward finite difference scheme. This numerical technique evades the recovery of the primitive vector by solving an algebraic system of equations as it is often used and so, it generalises standard techniques to solve these kind of coupled systems. The article is presented bearing in mind special relativistic hydrodynamic numerical schemes with an added pedagogical view in the appendix section in order to easily comprehend the PVRS. We present the convergence of the method for standard shock-tube problems of special relativistic hydrodynamics and a graphical visualisation of the errors using the fluctuations of the numerical values with respect to exact analytic solutions. The PVRS circumvents the sometimes arduous computation that arises from standard numerical methods techniques, which obtain the desired primitive vector solution through an algebraic polynomial of the charges.

  20. Strong Carrier-Phonon Coupling in Lead Halide Perovskite Nanocrystals

    NARCIS (Netherlands)

    Iaru, Claudiu M; Geuchies, Jaco J|info:eu-repo/dai/nl/370526090; Koenraad, Paul M; Vanmaekelbergh, Daniël|info:eu-repo/dai/nl/304829137; Silov, Andrei Yu

    2017-01-01

    We highlight the importance of carrier-phonon coupling in inorganic lead halide perovskite nanocrystals. The low-temperature photoluminescence (PL) spectrum of CsPbBr3 has been investigated under a nonresonant and a nonstandard, quasi-resonant excitation scheme, and phonon replicas of the main PL

  1. Coupled-core fluxgate magnetometer: Novel configuration scheme and the effects of a noise-contaminated external signal

    International Nuclear Information System (INIS)

    Palacios, Antonio; Aven, John; In, Visarath; Longhini, Patrick; Kho, Andy; Neff, Joseph D.; Bulsara, Adi

    2007-01-01

    Recent theoretical and experimental work has shown that unidirectional coupling can induce oscillations in overdamped and undriven nonlinear dynamical systems that are non-oscillatory when uncoupled; in turn, this has been shown to lead to new mechanisms for weak (compared to the energy barrier height) signal detection and amplification. The potential applications include fluxgate magnetometers, electric field sensors, and arrays of Superconducting Quantum Interference Device (SQUID) rings. In the particular case of the fluxgate magnetometer, we have developed a ''coupled-core fluxgate magnetometer'' (CCFM); this device has been realized in the laboratory and its dynamics used to quantify many properties that are generic to this class of systems and coupling. The CCFM operation is underpinned by the emergent oscillatory behavior in a unidirectionally coupled ring of wound ferromagnetic cores, each of which can be treated as an overdamped bistable dynamic system when uncoupled. In particular, one can determine the regimes of existence and stability of the (coupling-induced) oscillations, and the scaling behavior of the oscillation frequency. More recently, we studied the effects of a (Gaussian) magnetic noise floor on a CCFM system realized with N=3 coupled ferromagnetic cores. In this Letter, we first introduce a variation on the basic CCFM configuration that affords a path to enhanced device sensitivity, particularly for N>=3 coupled elements. We then analyze the response of the basic CCFM configuration as well as the new setup to a dc target signal that has a small noisy component (or ''contamination'')

  2. Programming scheme based optimization of hybrid 4T-2R OxRAM NVSRAM

    Science.gov (United States)

    Majumdar, Swatilekha; Kingra, Sandeep Kaur; Suri, Manan

    2017-09-01

    In this paper, we present a novel single-cycle programming scheme for 4T-2R NVSRAM, exploiting pulse engineered input signals. OxRAM devices based on 3 nm thick bi-layer active switching oxide and 90 nm CMOS technology node were used for all simulations. The cell design is implemented for real-time non-volatility rather than last-bit, or power-down non-volatility. Detailed analysis of the proposed single-cycle, parallel RRAM device programming scheme is presented in comparison to the two-cycle sequential RRAM programming used for similar 4T-2R NVSRAM bit-cells. The proposed single-cycle programming scheme coupled with the 4T-2R architecture leads to several benefits such as- possibility of unconventional transistor sizing, 50% lower latency, 20% improvement in SNM and ∼20× reduced energy requirements, when compared against two-cycle programming approach.

  3. On coupling fluid plasma and kinetic neutral physics models

    Directory of Open Access Journals (Sweden)

    I. Joseph

    2017-08-01

    Full Text Available The coupled fluid plasma and kinetic neutral physics equations are analyzed through theory and simulation of benchmark cases. It is shown that coupling methods that do not treat the coupling rates implicitly are restricted to short time steps for stability. Fast charge exchange, ionization and recombination coupling rates exist, even after constraining the solution by requiring that the neutrals are at equilibrium. For explicit coupling, the present implementation of Monte Carlo correlated sampling techniques does not allow for complete convergence in slab geometry. For the benchmark case, residuals decay with particle number and increase with grid size, indicating that they scale in a manner that is similar to the theoretical prediction for nonlinear bias error. Progress is reported on implementation of a fully implicit Jacobian-free Newton–Krylov coupling scheme. The present block Jacobi preconditioning method is still sensitive to time step and methods that better precondition the coupled system are under investigation.

  4. QuBiLS-MIDAS: a parallel free-software for molecular descriptors computation based on multilinear algebraic maps.

    Science.gov (United States)

    García-Jacas, César R; Marrero-Ponce, Yovani; Acevedo-Martínez, Liesner; Barigye, Stephen J; Valdés-Martiní, José R; Contreras-Torres, Ernesto

    2014-07-05

    The present report introduces the QuBiLS-MIDAS software belonging to the ToMoCoMD-CARDD suite for the calculation of three-dimensional molecular descriptors (MDs) based on the two-linear (bilinear), three-linear, and four-linear (multilinear or N-linear) algebraic forms. Thus, it is unique software that computes these tensor-based indices. These descriptors, establish relations for two, three, and four atoms by using several (dis-)similarity metrics or multimetrics, matrix transformations, cutoffs, local calculations and aggregation operators. The theoretical background of these N-linear indices is also presented. The QuBiLS-MIDAS software was developed in the Java programming language and employs the Chemical Development Kit library for the manipulation of the chemical structures and the calculation of the atomic properties. This software is composed by a desktop user-friendly interface and an Abstract Programming Interface library. The former was created to simplify the configuration of the different options of the MDs, whereas the library was designed to allow its easy integration to other software for chemoinformatics applications. This program provides functionalities for data cleaning tasks and for batch processing of the molecular indices. In addition, it offers parallel calculation of the MDs through the use of all available processors in current computers. The studies of complexity of the main algorithms demonstrate that these were efficiently implemented with respect to their trivial implementation. Lastly, the performance tests reveal that this software has a suitable behavior when the amount of processors is increased. Therefore, the QuBiLS-MIDAS software constitutes a useful application for the computation of the molecular indices based on N-linear algebraic maps and it can be used freely to perform chemoinformatics studies. Copyright © 2014 Wiley Periodicals, Inc.

  5. The detailed snowpack scheme Crocus and its implementation in SURFEX v7.2

    Science.gov (United States)

    Vionnet, V.; Brun, E.; Morin, S.; Boone, A.; Faroux, S.; Le Moigne, P.; Martin, E.; Willemet, J.-M.

    2012-05-01

    Detailed studies of snow cover processes require models that offer a fine description of the snow cover properties. The detailed snowpack model Crocus is such a scheme, and has been run operationally for avalanche forecasting over the French mountains for 20 yr. It is also used for climate or hydrological studies. To extend its potential applications, Crocus has been recently integrated within the framework of the externalized surface module SURFEX. SURFEX computes the exchanges of energy and mass between different types of surface and the atmosphere. It includes in particular the land surface scheme ISBA (Interactions between Soil, Biosphere, and Atmosphere). It allows Crocus to be run either in stand-alone mode, using a time series of forcing meteorological data or in fully coupled mode (explicit or fully implicit numerics) with atmospheric models ranging from meso-scale models to general circulation models. This approach also ensures a full coupling between the snow cover and the soil beneath. Several applications of this new simulation platform are presented. They range from a 1-D stand-alone simulation (Col de Porte, France) to fully-distributed simulations in complex terrain over a whole mountain range (Massif des Grandes Rousses, France), or in coupled mode such as a surface energy balance and boundary layer simulation over the East Antarctic Ice Sheet (Dome C).

  6. Macroscopic Entangled State Generation with Optomechanical Coupling of Two Mechanical Modes

    Science.gov (United States)

    Weaver, Matthew; Luna, Fernando; Buters, Frank; Heeck, Kier; de Man, Sven; Bouwmeester, Dirk

    Mechanical resonators with a large quantum position uncertainty are an excellent test system for proposed decoherence mechanisms in massive systems. We present a scheme to optomechanically entangle two mechanical resonators with large frequency separation via two tone driving and single photon projection measurements. The quantum position uncertainty can be tuned with a variable optical pulse displacement operation, and independent single photon readout of the two resonators provides robust verification of the quantum states of the system. This scheme is currently experimentally feasible in a number of high mass opto- and electro-mechanical systems. We demonstrate one such system with two spatially and frequency separated Si3N4 trampoline resonators. We also show how the resonators can be coupled with two tone driving and the single photon optomechanical coupling rates can be tuned.

  7. Impact of Convection and Long Range Transport on Short-Lived Trace Gases in the UT/LS

    Science.gov (United States)

    Atlas, E. L.; Schauffler, S.; Navarro, M. A.; Lueb, R.; Hendershot, R.; Ueyama, R.

    2017-12-01

    Chemical composition of the air in the upper troposphere/lower stratosphere is controlled by a balance of transport, photochemistry, and physical processes, such as interactions with clouds, ice, and aerosol. The chemistry of the air masses that reach the upper troposphere can potentially have profound impacts on the chemistry in the near tropopause region. For example, the transport of reactive organic halogens and their transformation to inorganic halogen species, e.g., Br, BrO, etc., can have a significant impact on ozone budgets in this region and even deeper the stratosphere. Trace gas measurements in the region near the tropopause can also indicate potential sources of surface emissions that are transported to high altitudes. Measurement of trace gases, including such compounds as non-methane hydrocarbons, hydrochlorofluorocarbons, halogenated solvents, methyl halides, etc., can be used to characterize source emissions from industrial, urban, biomass burning, or marine origins. Recent airborne research campaigns have been conducted to better characterize the chemical composition and variations in the UT/LS region. This presentation will discuss these measurements, with a special emphasis on the role of convection and transport in modifying the chemical composition of the UT/LS.

  8. ASSOCIATING LONG-TERM γ-RAY VARIABILITY WITH THE SUPERORBITAL PERIOD OF LS I +61°303

    International Nuclear Information System (INIS)

    Ackermann, M.; Buehler, R.; Ajello, M.; Ballet, J.; Casandjian, J. M.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bellazzini, R.; Bregeon, J.; Bonamente, E.; Cecchi, C.; Brandt, T. J.; Brigida, M.; Bruel, P.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cavazzuti, E.; Chekhtman, A.

    2013-01-01

    Gamma-ray binaries are stellar systems for which the spectral energy distribution (discounting the thermal stellar emission) peaks at high energies. Detected from radio to TeV gamma rays, the γ-ray binary LS I +61°303 is highly variable across all frequencies. One aspect of this system's variability is the modulation of its emission with the timescale set by the ∼26.4960 day orbital period. Here we show that, during the time of our observations, the γ-ray emission of LS I +61°303 also presents a sinusoidal variability consistent with the previously known superorbital period of 1667 days. This modulation is more prominently seen at orbital phases around apastron, whereas it does not introduce a visible change close to periastron. It is also found in the appearance and disappearance of variability at the orbital period in the power spectrum of the data. This behavior could be explained by a quasi-cyclical evolution of the equatorial outflow of the Be companion star, whose features influence the conditions for generating gamma rays. These findings open the possibility to use γ-ray observations to study the outflows of massive stars in eccentric binary systems

  9. Higher Loop Corrections to the Infrared Evolution of Fermionic Gauge Theories in the RI' Scheme

    DEFF Research Database (Denmark)

    Ryttov, Thomas

    2014-01-01

    We study the evolution of the gauge coupling and the anomalous dimension of the mass towards an infrared fixed point for non-supersymmetric gauge theories in the modified regularization invariant, RI', scheme. This is done at the three loop level where all the renormalization group functions have...

  10. Event-driven simulation of neural population synchronization facilitated by electrical coupling.

    Science.gov (United States)

    Carrillo, Richard R; Ros, Eduardo; Barbour, Boris; Boucheny, Christian; Coenen, Olivier

    2007-02-01

    Most neural communication and processing tasks are driven by spikes. This has enabled the application of the event-driven simulation schemes. However the simulation of spiking neural networks based on complex models that cannot be simplified to analytical expressions (requiring numerical calculation) is very time consuming. Here we describe briefly an event-driven simulation scheme that uses pre-calculated table-based neuron characterizations to avoid numerical calculations during a network simulation, allowing the simulation of large-scale neural systems. More concretely we explain how electrical coupling can be simulated efficiently within this computation scheme, reproducing synchronization processes observed in detailed simulations of neural populations.

  11. Theories of quantum dissipation and nonlinear coupling bath descriptors

    Science.gov (United States)

    Xu, Rui-Xue; Liu, Yang; Zhang, Hou-Dao; Yan, YiJing

    2018-03-01

    The quest of an exact and nonperturbative treatment of quantum dissipation in nonlinear coupling environments remains in general an intractable task. In this work, we address the key issues toward the solutions to the lowest nonlinear environment, a harmonic bath coupled both linearly and quadratically with an arbitrary system. To determine the bath coupling descriptors, we propose a physical mapping scheme, together with the prescription reference invariance requirement. We then adopt a recently developed dissipaton equation of motion theory [R. X. Xu et al., Chin. J. Chem. Phys. 30, 395 (2017)], with the underlying statistical quasi-particle ("dissipaton") algebra being extended to the quadratic bath coupling. We report the numerical results on a two-level system dynamics and absorption and emission line shapes.

  12. Generalized Rashba-Dresselhaus spin-orbit coupling for cold atoms

    International Nuclear Information System (INIS)

    Juzeliunas, Gediminas; Ruseckas, Julius; Dalibard, Jean

    2010-01-01

    We study the possibility for generating a new type of spin-orbit coupling for the center-of-mass motion of cold atoms, using laser beams that resonantly couple N atomic internal ground states to an extra state. After a general analysis of the scheme, we concentrate on the tetrapod setup (N=4) where the atomic state can be described by a three-component spinor, evolving under the action of a Rashba-Dresselhaus-type spin-orbit coupling for a spin 1 particle. We illustrate a consequence of this coupling by studying the negative refraction of atoms at a potential step and show that the amplitude of the refracted beam is significantly increased in comparison to the known case of spin 1/2 Rashba-Dresselhaus coupling. Finally, we explore a possible implementation of this tetrapod setup, using stimulated Raman couplings between Zeeman sublevels of the ground state of alkali-metal atoms.

  13. Fingerprinting the extended Higgs sector using one-loop corrected Higgs boson couplings and future precision measurements

    Directory of Open Access Journals (Sweden)

    Shinya Kanemura

    2015-07-01

    Full Text Available We calculate radiative corrections to a full set of coupling constants for the 125 GeV Higgs boson at the one-loop level in two Higgs doublet models with four types of Yukawa interaction under the softly-broken discrete Z2 symmetry. The renormalization calculations are performed in the on-shell scheme, in which the gauge dependence in the mixing parameter which appears in the previous calculation is consistently avoided. We first show the details of our renormalization scheme, and present the complete set of the analytic formulae of the renormalized couplings. We then numerically demonstrate how the inner parameters of the model can be extracted by the future precision measurements of these couplings at the high luminosity LHC and the International Linear Collider.

  14. The detailed snowpack scheme Crocus and its implementation in SURFEX v7

    Science.gov (United States)

    Vionnet, V.; Brun, E.; Morin, S.; Boone, A.; Faroux, S.; Le Moigne, P.; Martin, E.; Willemet, J.-M.

    2011-09-01

    Detailed studies of snow cover processes require models that offer a fine description of the snow cover properties. The detailed snowpack model Crocus is such a scheme, and has been run operationally for avalanche forecasting over the French mountains for 20 years. It is also used for climate or hydrological studies. To extend its potential applications, Crocus has been recently integrated within the framework of the externalized surface module SURFEX. SURFEX computes the exchanges of energy and mass between different types of surface, and the atmosphere and includes in particular the land surface scheme ISBA (Interactions between Soil, Biosphere, and Atmosphere). It allows Crocus to be run either in stand-alone mode, using a time series of forcing meteorological data or in fully coupled mode (explicit or fully implicit numerics) with atmospheric models ranging from meso-scale models to general circulation models. This approach also insures a full coupling between the snow cover and the soil beneath. Several applications of this new simulation platform are presented. They range from a 1D stand-alone simulation (Col de Porte, France) to fully-distributed simulations in complex terrain, either in forced mode over a whole mountain range (Massif des Grandes Rousses, France), or in coupled mode such as a snow transport simulation (Col du Lac Blanc, France), or a surface energy balance and boundary layer simulation over a polar ice cap (Dome C, Antarctica).

  15. All you need is shape: Predicting shear banding in sand with LS-DEM

    Science.gov (United States)

    Kawamoto, Reid; Andò, Edward; Viggiani, Gioacchino; Andrade, José E.

    2018-02-01

    This paper presents discrete element method (DEM) simulations with experimental comparisons at multiple length scales-underscoring the crucial role of particle shape. The simulations build on technological advances in the DEM furnished by level sets (LS-DEM), which enable the mathematical representation of the surface of arbitrarily-shaped particles such as grains of sand. We show that this ability to model shape enables unprecedented capture of the mechanics of granular materials across scales ranging from macroscopic behavior to local behavior to particle behavior. Specifically, the model is able to predict the onset and evolution of shear banding in sands, replicating the most advanced high-fidelity experiments in triaxial compression equipped with sequential X-ray tomography imaging. We present comparisons of the model and experiment at an unprecedented level of quantitative agreement-building a one-to-one model where every particle in the more than 53,000-particle array has its own avatar or numerical twin. Furthermore, the boundary conditions of the experiment are faithfully captured by modeling the membrane effect as well as the platen displacement and tilting. The results show a computational tool that can give insight into the physics and mechanics of granular materials undergoing shear deformation and failure, with computational times comparable to those of the experiment. One quantitative measure that is extracted from the LS-DEM simulations that is currently not available experimentally is the evolution of three dimensional force chains inside and outside of the shear band. We show that the rotations on the force chains are correlated to the rotations in stress principal directions.

  16. Coupled-core fluxgate magnetometer: Novel configuration scheme and the effects of a noise-contaminated external signal

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, Antonio [San Diego State University, Nonlinear Dynamical Systems Group, Department of Mathematics and Statistics, San Diego, CA 92182-7720 (United States)]. E-mail: palacios@euler.sdsu.edu; Aven, John [San Diego State University, Nonlinear Dynamical Systems Group, Department of Mathematics and Statistics, San Diego, CA 92182-7720 (United States); In, Visarath [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull St, San Diego, CA 92152-5001 (United States)]. E-mail: visarath@spawar.navy.mil; Longhini, Patrick [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull St, San Diego, CA 92152-5001 (United States); Kho, Andy [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull St, San Diego, CA 92152-5001 (United States); Neff, Joseph D. [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull St, San Diego, CA 92152-5001 (United States); Bulsara, Adi [Space and Naval Warfare Systems Center San Diego, Code 2363, 53560 Hull St, San Diego, CA 92152-5001 (United States)]. E-mail: bulsara@spawar.navy.mil

    2007-07-16

    Recent theoretical and experimental work has shown that unidirectional coupling can induce oscillations in overdamped and undriven nonlinear dynamical systems that are non-oscillatory when uncoupled; in turn, this has been shown to lead to new mechanisms for weak (compared to the energy barrier height) signal detection and amplification. The potential applications include fluxgate magnetometers, electric field sensors, and arrays of Superconducting Quantum Interference Device (SQUID) rings. In the particular case of the fluxgate magnetometer, we have developed a ''coupled-core fluxgate magnetometer'' (CCFM); this device has been realized in the laboratory and its dynamics used to quantify many properties that are generic to this class of systems and coupling. The CCFM operation is underpinned by the emergent oscillatory behavior in a unidirectionally coupled ring of wound ferromagnetic cores, each of which can be treated as an overdamped bistable dynamic system when uncoupled. In particular, one can determine the regimes of existence and stability of the (coupling-induced) oscillations, and the scaling behavior of the oscillation frequency. More recently, we studied the effects of a (Gaussian) magnetic noise floor on a CCFM system realized with N=3 coupled ferromagnetic cores. In this Letter, we first introduce a variation on the basic CCFM configuration that affords a path to enhanced device sensitivity, particularly for N>=3 coupled elements. We then analyze the response of the basic CCFM configuration as well as the new setup to a dc target signal that has a small noisy component (or ''contamination'')

  17. Scheme dependence of quantum gravity on de Sitter background

    Energy Technology Data Exchange (ETDEWEB)

    Kitamoto, Hiroyuki, E-mail: kitamoto@post.kek.jp [KEK Theory Center, Tsukuba, Ibaraki 305-0801 (Japan); Kitazawa, Yoshihisa, E-mail: kitazawa@post.kek.jp [KEK Theory Center, Tsukuba, Ibaraki 305-0801 (Japan); The Graduate University for Advanced Studies (Sokendai), Department of Particle and Nuclear Physics, Tsukuba, Ibaraki 305-0801 (Japan)

    2013-08-11

    We extend our investigation of the IR effects on the local dynamics of matter fields in quantum gravity. Specifically we clarify how the IR effects depend on the change of the quantization scheme: different parametrization of the metric and the matter field redefinition. Conformal invariance implies effective Lorentz invariance of the matter system in de Sitter space. An arbitrary choice of the parametrization of the metric and the matter field redefinition does not preserve the effective Lorentz invariance of the local dynamics. As for the effect of different parametrization of the metric alone, the effective Lorentz symmetry breaking term can be eliminated by shifting the background metric. In contrast, we cannot compensate the matter field redefinition dependence by such a way. The effective Lorentz invariance can be retained only when we adopt the specific matter field redefinitions where all dimensionless couplings become scale invariant at the classical level. This scheme is also singled out by unitarity as the kinetic terms are canonically normalized.

  18. Gene expression profiling upon 212Pb-TCMC-trastuzumab treatment in the LS-174T i.p. xenograft model

    International Nuclear Information System (INIS)

    Yong, Kwon J; Milenic, Diane E; Baidoo, Kwamena E; Kim, Young-Seung; Brechbiel, Martin W

    2013-01-01

    Recent studies have demonstrated that therapy with 212 Pb-TCMC-trastuzumab resulted in (1) induction of apoptosis, (2) G2/M arrest, and (3) blockage of double-strand DNA damage repair in LS-174T i.p. (intraperitoneal) xenografts. To further understand the molecular basis of the cell killing efficacy of 212 Pb-TCMC-trastuzumab, gene expression profiling was performed with LS-174T xenografts 24 h after exposure to 212 Pb-TCMC-trastuzumab. DNA damage response genes (84) were screened using a quantitative real-time polymerase chain reaction array (qRT-PCR array). Differentially regulated genes were identified following exposure to 212 Pb-TCMC-trastuzumab. These included genes involved in apoptosis (ABL, GADD45α, GADD45γ, PCBP4, and p73), cell cycle (ATM, DDIT3, GADD45α, GTSE1, MKK6, PCBP4, and SESN1), and damaged DNA binding (DDB) and repair (ATM and BTG2). The stressful growth arrest conditions provoked by 212 Pb-TCMC-trastuzumab were found to induce genes involved in apoptosis and cell cycle arrest in the G2/M phase. The expression of genes involved in DDB and single-strand DNA breaks was also enhanced by 212 Pb-TCMC-trastuzumab while no modulation of genes involved in double-strand break repair was apparent. Furthermore, the p73/GADD45 signaling pathway mediated by p38 kinase signaling may be involved in the cellular response, as evidenced by the enhanced expression of genes and proteins of this pathway. These results further support the previously described cell killing mechanism by 212 Pb-TCMC-trastuzumab in the same LS-174T i.p. xenograft. Insight into these mechanisms could lead to improved strategies for rational application of radioimmunotherapy using α-particle emitters. The apoptotic response and associated gene modulations have not been clearly defined following exposure of cells to α-particle radioimmunotherapy (RIT). Gene expression profiling was performed with LS-174T i.p. (intraperitoneal) xenografts after exposure to 212 Pb

  19. Strong coupling in a gauge invariant field theory

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, K. [Physics Department, Massachusetts Institute of Technology, Cambridge, MA (United States)

    1963-01-15

    I would like to discuss some approximations which may be significant in the domain of strong coupling in a field system analogous to quantum electrodynamics. The motivation of this work is the idea that the strong couplings and elementary particle spectrum may be the consequence of the dynamics of a system whose underlying description is in terms of a set of Fermi fields gauge invariantly coupled to a single (''bare'') massless neutral vector field. The basis of this gauge invariance would of course be the exact conservation law of baryons or ''nucleonic charge''. It seems to me that a coupling scheme based on an invariance principle is most attractive if that invariance is an exact one. It would then be nice to try to account for the approximate invariance principles in the same way one would describe ''accidental degeneracies'' in any quantum system.

  20. Stable integrated hyper-parametric oscillator based on coupled optical microcavities.

    Science.gov (United States)

    Armaroli, Andrea; Feron, Patrice; Dumeige, Yannick

    2015-12-01

    We propose a flexible scheme based on three coupled optical microcavities that permits us to achieve stable oscillations in the microwave range, the frequency of which depends only on the cavity coupling rates. We find that the different dynamical regimes (soft and hard excitation) affect the oscillation intensity, but not their periods. This configuration may permit us to implement compact hyper-parametric sources on an integrated optical circuit with interesting applications in communications, sensing, and metrology.

  1. Development of a signal-extraction scheme for resonant sideband extraction

    International Nuclear Information System (INIS)

    Kokeyama, K; Kawazoe, F; Sugamoto, A; Somiya, K; Sato, S; Kawamura, S

    2008-01-01

    As a future plan, an advanced gravitational-wave detector will employ an optical configuration of resonant sideband extraction (RSE), achieved with an additional mirror at the signal-detection port of the power-recycled Fabry-Perot Michelson interferometer. To control the complex coupled cavity system, one of the most important design issues is how to extract the longitudinal control signals of the cavities. We have developed a new signal-extraction scheme which provides an appropriate sensing matrix. The new method uses two sets of sidebands: one of the sideband components satisfies the critical coupling condition for the RSE interferometer and reaches the signal-extraction port, and the other sideband is completely reflected by the Michelson interferometer. They provide a diagonalized sensing matrix and enable the RSE control to be robust

  2. An effective parameter optimization technique for vibration flow field characterization of PP melts via LS-SVM combined with SALS in an electromagnetism dynamic extruder

    Science.gov (United States)

    Xian, Guangming

    2018-03-01

    A method for predicting the optimal vibration field parameters by least square support vector machine (LS-SVM) is presented in this paper. One convenient and commonly used technique for characterizing the the vibration flow field of polymer melts films is small angle light scattering (SALS) in a visualized slit die of the electromagnetism dynamic extruder. The optimal value of vibration vibration frequency, vibration amplitude, and the maximum light intensity projection area can be obtained by using LS-SVM for prediction. For illustrating this method and show its validity, the flowing material is used with polypropylene (PP) and fifteen samples are tested at the rotation speed of screw at 36rpm. This paper first describes the apparatus of SALS to perform the experiments, then gives the theoretical basis of this new method, and detail the experimental results for parameter prediction of vibration flow field. It is demonstrated that it is possible to use the method of SALS and obtain detailed information on optimal parameter of vibration flow field of PP melts by LS-SVM.

  3. Coupling a system code with computational fluid dynamics for the simulation of complex coolant reactivity effects

    International Nuclear Information System (INIS)

    Bertolotto, D.

    2011-11-01

    The current doctoral research is focused on the development and validation of a coupled computational tool, to combine the advantages of computational fluid dynamics (CFD) in analyzing complex flow fields and of state-of-the-art system codes employed for nuclear power plant (NPP) simulations. Such a tool can considerably enhance the analysis of NPP transient behavior, e.g. in the case of pressurized water reactor (PWR) accident scenarios such as Main Steam Line Break (MSLB) and boron dilution, in which strong coolant flow asymmetries and multi-dimensional mixing effects strongly influence the reactivity of the reactor core, as described in Chap. 1. To start with, a literature review on code coupling is presented in Chap. 2, together with the corresponding ongoing projects in the international community. Special reference is made to the framework in which this research has been carried out, i.e. the Paul Scherrer Institute's (PSI) project STARS (Steady-state and Transient Analysis Research for the Swiss reactors). In particular, the codes chosen for the coupling, i.e. the CFD code ANSYS CFX V11.0 and the system code US-NRC TRACE V5.0, are part of the STARS codes system. Their main features are also described in Chap. 2. The development of the coupled tool, named CFX/TRACE from the names of the two constitutive codes, has proven to be a complex and broad-based task, and therefore constraints had to be put on the target requirements, while keeping in mind a certain modularity to allow future extensions to be made with minimal efforts. After careful consideration, the coupling was defined to be on-line, parallel and with non-overlapping domains connected by an interface, which was developed through the Parallel Virtual Machines (PVM) software, as described in Chap. 3. Moreover, two numerical coupling schemes were implemented and tested: a sequential explicit scheme and a sequential semi-implicit scheme. Finally, it was decided that the coupling would be single

  4. LS1 Report: the electric atmosphere of the LHC

    CERN Multimedia

    Simon Baird

    2013-01-01

    In the LHC, testing of the main magnet (dipole and quadrupole) circuits has been completed. At the same time, the extensive tests of all the other circuits up to current levels corresponding to 7 TeV beam operation have been performed, and now the final ElQA (Electrical Quality Assurance) tests of the electrical circuits are proceeding.   In Sectors 4-5 and 5-6, where the ElQA checks have been finished, the process of removing and storing the helium has started (see the article Heatwave warning for the LHC, in this issue). This is the first step in warming up the whole machine to room temperature so that the main LS1 activities, SMACC (Super Conducting Magnet and Circuit Consolidation) and the R2E (Radiation Two Electronics) programmes, which are scheduled to start on 19 April and 22 March respectively, can get under way. As far as the LHC injectors are concerned, LINAC2 and the PS Booster are in shutdown mode, having completed their preparatory hardware test programmes, and shutdown work has alr...

  5. LS1 Report: antimatter research on the starting blocks

    CERN Multimedia

    Antonella Del Rosso

    2014-01-01

    The consolidation work at the Antiproton Decelerator (AD) has been very intensive and the operators now have a basically new machine to “drive”. Thanks to the accurate preparation work still ongoing, the machine will soon deliver its first beam of antiprotons to the experiments. The renewed efficiency of the whole complex will ensure the best performance of the whole of CERN’s antimatter research programme in the long term.   The test bench for the new Magnetic Horn stripline. On the left, high voltage cables are connected to the stripline, which then feeds a 6 kV 400 kA pulse to the Horn. The Horn itself (the cylindrical object on the right) can be seen mounted on its chariot. The consolidation programme at the AD planned during LS1 has involved some of the most vital parts of the decelerator such as the target area, the ring magnets, the stochastic cooling system, vacuum system, control system and various aspects of the instrumentation. In addit...

  6. LS1 Report: on the home straight in 2014

    CERN Multimedia

    Anaïs Schaeffer

    2013-01-01

    At 7.24 a.m. on 14 February 2013 the last beams for physics were absorbed into the LHC, marking the end of Run 1. The achievements since then over the first ten months of LS1 have been remarkable. The excellent progress of the maintenance work on CERN's accelerators, which is overwhelmingly on schedule – and even ahead of schedule in some cases! – was praised by the CERN Council last week.   That being said, there is still a long way to go before the LHC re-start, with many challenges and potential pitfalls to be overcome. An overview of what still lies ahead: For the injectors (Linac 2, PS booster, LEIR, PS and AD), 2014 will begin with the recommissioning of all the access systems (scheduled for mid-February). The first power tests (to check the magnets and the power converters) will follow hot on its heels, starting in early April in the case of the PS booster. The final power tests of the injectors will be carried out at the Antiproton Decelerator in June. Th...

  7. The running coupling of QCD with four flavors

    International Nuclear Information System (INIS)

    Tekin, Fatih; Wolff, Ulli; Sommer, Rainer

    2010-06-01

    We have calculated the step scaling function and the running coupling of QCD in the Schroedinger functional scheme with four flavors of O(a) improved Wilson quarks. Comparisons of our non-perturbative results with 2-loop and 3-loop perturbation theory as well as with non-perturbative data for only two flavors are made. (orig.)

  8. Further optimization of a parallel double-effect organosilicon distillation scheme through exergy analysis

    International Nuclear Information System (INIS)

    Sun, Jinsheng; Dai, Leilei; Shi, Ming; Gao, Hong; Cao, Xijia; Liu, Guangxin

    2014-01-01

    In our previous work, a significant improvement in organosilicon monomer distillation using parallel double-effect heat integration between a heavies removal column and six other columns, as well as heat integration between methyltrichlorosilane and dimethylchlorosilane columns, reduced the total exergy loss of the currently running counterpart by 40.41%. Further research regarding this optimized scheme demonstrated that it was necessary to reduce the higher operating pressure of the methyltrichlorosilane column, which is required for heat integration between the methyltrichlorosilane and dimethylchlorosilane columns. Therefore, in this contribution, a challenger scheme is presented with heat pumps introduced separately from the originally heat-coupled methyltrichlorosilane and dimethylchlorosilane columns in the above-mentioned optimized scheme, which is the prototype for this work. Both schemes are simulated using the same purity requirements used in running industrial units. The thermodynamic properties from the simulation are used to calculate the energy consumption and exergy loss of the two schemes. The results show that the heat pump option further reduces the flowsheet energy consumption and exergy loss by 27.35% and 10.98% relative to the prototype scheme. These results indicate that the heat pumps are superior to heat integration in the context of energy-savings during organosilicon monomer distillation. - Highlights: • Combine the paralleled double-effect and heat pump distillation to organosilicon distillation. • Compare the double-effect with the heat pump in saving energy. • Further cut down the flowsheet energy consumption and exergy loss by 27.35% and 10.98% respectively

  9. Three-gluon running coupling from lattice QCD at N{sub f}=2+1+1: a consistency check of the OPE approach

    Energy Technology Data Exchange (ETDEWEB)

    Boucaud, Ph. [Laboratoire Physique Théorique, Université de Paris XI,Bâtiment 210, 91405 Orsay Cedex (France); Brinet, M. [Laboratoire de Physique Subatomique et de Cosmologie, CNRS/IN2P3/UJF,53, avenue des Martyrs, 38026 Grenoble (France); Soto, F. De [Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide,41013 Sevilla (Spain); Morenas, V. [Laboratoire de Physique Corpusculaire, Université Blaise Pascal, CNRS/IN2P3,63177 Aubière Cedex (France); Pène, O. [Laboratoire Physique Théorique, Université de Paris XI,Bâtiment 210, 91405 Orsay Cedex (France); Petrov, K. [Laboratoire de l’Accélérateur Linéaire, Centre Scientifique d’Orsay,Bâtiment 200, 91898 ORSAY Cedex (France); Rodríguez-Quintero, J. [Departamento de Física Aplicada, Facultad de Ciencias Experimentales, Universidad de Huelva,21071 Huelva (Spain); CAFPE, Universidad de Granada,E-18071 Granada (Spain)

    2014-04-11

    We present a lattice calculation of the renormalized running coupling constant in symmetric (MOM) and asymmetric ( (MOM)-tilde ) momentum substraction schemes including u, d, s and c quarks in the sea. An Operator Product Expansion dominated by the dimension-two 〈A{sup 2}〉 condensate is used to fit the running of the coupling. We argue that the agreement in the predicted 〈A{sup 2}〉 condensate for both schemes is a strong support for the validity of the OPE approach and the effect of this non-gauge invariant condensate over the running of the strong coupling.

  10. Ballistic Simulation Method for Lithium Ion Batteries (BASIMLIB) Using Thick Shell Composites (TSC) in LS-DYNA

    Science.gov (United States)

    2016-08-04

    BAllistic SImulation Method for Lithium Ion Batteries (BASIMLIB) using Thick Shell Composites (TSC) in LS-DYNA Venkatesh Babu, Dr. Matt Castanier, Dr...and behavior of the cells through experimental and modeling at their crash worthiness laboratory • Most of the simulation work on the batteries are...at a single cell level and gap exists to simulate the batteries at their full pack capacity - Firstly, requires an enormous amount of computational

  11. Investigation on a coupled CFD/DSMC method for continuum-rarefied flows

    Science.gov (United States)

    Tang, Zhenyu; He, Bijiao; Cai, Guobiao

    2012-11-01

    The purpose of the present work is to investigate the coupled CFD/DSMC method using the existing CFD and DSMC codes developed by the authors. The interface between the continuum and particle regions is determined by the gradient-length local Knudsen number. A coupling scheme combining both state-based and flux-based coupling methods is proposed in the current study. Overlapping grids are established between the different grid systems of CFD and DSMC codes. A hypersonic flow over a 2D cylinder has been simulated using the present coupled method. Comparison has been made between the results obtained from both methods, which shows that the coupled CFD/DSMC method can achieve the same precision as the pure DSMC method and obtain higher computational efficiency.

  12. Aerosols in the tropical and subtropical UT/LS: in-situ measurements of submicron particle abundance and volatility

    Directory of Open Access Journals (Sweden)

    S. Borrmann

    2010-06-01

    Full Text Available Processes occurring in the tropical upper troposphere (UT, the Tropical Transition Layer (TTL, and the lower stratosphere (LS are of importance for the global climate, for stratospheric dynamics and air chemistry, and for their influence on the global distribution of water vapour, trace gases and aerosols. In this contribution we present aerosol and trace gas (in-situ measurements from the tropical UT/LS over Southern Brazil, Northern Australia, and West Africa. The instruments were operated on board of the Russian high altitude research aircraft M-55 "Geophysica" and the DLR Falcon-20 during the campaigns TROCCINOX (Araçatuba, Brazil, February 2005, SCOUT-O3 (Darwin, Australia, December 2005, and SCOUT-AMMA (Ouagadougou, Burkina Faso, August 2006. The data cover submicron particle number densities and volatility from the COndensation PArticle counting System (COPAS, as well as relevant trace gases like N2O, ozone, and CO. We use these trace gas measurements to place the aerosol data into a broader atmospheric context. Also a juxtaposition of the submicron particle data with previous measurements over Costa Rica and other tropical locations between 1999 and 2007 (NASA DC-8 and NASA WB-57F is provided. The submicron particle number densities, as a function of altitude, were found to be remarkably constant in the tropical UT/LS altitude band for the two decades after 1987. Thus, a parameterisation suitable for models can be extracted from these measurements. Compared to the average levels in the period between 1987 and 2007 a slight increase of particle abundances was found for 2005/2006 at altitudes with potential temperatures, Θ, above 430 K. The origins of this increase are unknown except for increases measured during SCOUT-AMMA. Here the eruption of the Soufrière Hills volcano in the Caribbean caused elevated particle mixing ratios. The vertical profiles from Northern hemispheric mid-latitudes between 1999 and 2006 also are

  13. A Layered Searchable Encryption Scheme with Functional Components Independent of Encryption Methods

    Science.gov (United States)

    Luo, Guangchun; Qin, Ke

    2014-01-01

    Searchable encryption technique enables the users to securely store and search their documents over the remote semitrusted server, which is especially suitable for protecting sensitive data in the cloud. However, various settings (based on symmetric or asymmetric encryption) and functionalities (ranked keyword query, range query, phrase query, etc.) are often realized by different methods with different searchable structures that are generally not compatible with each other, which limits the scope of application and hinders the functional extensions. We prove that asymmetric searchable structure could be converted to symmetric structure, and functions could be modeled separately apart from the core searchable structure. Based on this observation, we propose a layered searchable encryption (LSE) scheme, which provides compatibility, flexibility, and security for various settings and functionalities. In this scheme, the outputs of the core searchable component based on either symmetric or asymmetric setting are converted to some uniform mappings, which are then transmitted to loosely coupled functional components to further filter the results. In such a way, all functional components could directly support both symmetric and asymmetric settings. Based on LSE, we propose two representative and novel constructions for ranked keyword query (previously only available in symmetric scheme) and range query (previously only available in asymmetric scheme). PMID:24719565

  14. Comparative study of numerical schemes of TVD3, UNO3-ACM and optimized compact scheme

    Science.gov (United States)

    Lee, Duck-Joo; Hwang, Chang-Jeon; Ko, Duck-Kon; Kim, Jae-Wook

    1995-01-01

    Three different schemes are employed to solve the benchmark problem. The first one is a conventional TVD-MUSCL (Monotone Upwind Schemes for Conservation Laws) scheme. The second scheme is a UNO3-ACM (Uniformly Non-Oscillatory Artificial Compression Method) scheme. The third scheme is an optimized compact finite difference scheme modified by us: the 4th order Runge Kutta time stepping, the 4th order pentadiagonal compact spatial discretization with the maximum resolution characteristics. The problems of category 1 are solved by using the second (UNO3-ACM) and third (Optimized Compact) schemes. The problems of category 2 are solved by using the first (TVD3) and second (UNO3-ACM) schemes. The problem of category 5 is solved by using the first (TVD3) scheme. It can be concluded from the present calculations that the Optimized Compact scheme and the UN03-ACM show good resolutions for category 1 and category 2 respectively.

  15. Safety and pharmacokinetics of the Fc-modified HIV-1 human monoclonal antibody VRC01LS: A Phase 1 open-label clinical trial in healthy adults

    OpenAIRE

    Gaudinski, Martin R.; Coates, Emily E.; Houser, Katherine V.; Chen, Grace L.; Yamshchikov, Galina; Saunders, Jamie G.; Holman, LaSonji A.; Gordon, Ingelise; Plummer, Sarah; Hendel, Cynthia S.; Conan-Cibotti, Michelle; Lorenzo, Margarita Gomez; Sitar, Sandra; Carlton, Kevin; Laurencot, Carolyn

    2018-01-01

    Background VRC01 is a human broadly neutralizing monoclonal antibody (bnMAb) against the CD4-binding site of the HIV-1 envelope glycoprotein (Env) that is currently being evaluated in a Phase IIb adult HIV-1 prevention efficacy trial. VRC01LS is a modified version of VRC01, designed for extended serum half-life by increased binding affinity to the neonatal Fc receptor. Methods and findings This Phase I dose-escalation study of VRC01LS in HIV-negative healthy adults was conducted by the Vaccin...

  16. Effects of PKM2 Gene Silencing on the Proliferation and Apoptosis of Colorectal Cancer LS-147T and SW620 Cells

    Directory of Open Access Journals (Sweden)

    Ran Ao

    2017-07-01

    Full Text Available Background/Aims: This paper aims to explore the effects of pyruvate kinase (PK M2 gene silencing on the proliferation and apoptosis of colorectal cancer (CRC LS-147T and SW620 cells. Methods: CRC LS-147T and SW620 cells highly expressing PKM2 were randomly selected by quantitative real-time polymerase chain reaction (qRT-PCR and then assigned into the blank (no transfection, PKM2-shRNA (transfection with shRNA and empty plasmid (transfection with empty plasmid groups. Immunofluorescence was applied to detect PKM2 protein expression. qRT-PCR and Western blotting were conducted to assess mRNA and protein expression of PKM2, p53 and p21. The cell counting kit-8 (CCK-8 assay was used to assess cell proliferation. Flow cytometry was used to assess the cell cycle and apoptosis rate, and a senescence-associated β-galactosidase staining kit was used to assess cell senescence. Results: PKM2 exhibited high mRNA expression among CRC LS-147T and SW620 cells with remarkable protein expression noted in the cytoplasm and nucleus. The PKM2-shRNA group exhibited reduced PKM2 mRNA and protein expression, whereas p53 and p21 expression was increased compared with the blank and empty plasmid groups. Cell proliferation in PKM2-shRNA cells decreased significantly compared with the blank group and empty plasmid groups. The PKM2-shRNA group exhibited more cells in the G1 phase and fewer cells in the G2/M phase compared with the blank and empty plasmid groups. In addition, the PKM2-shRNA group exhibited significantly increased apoptosis rates and β-galactosidase activity compared with the blank and empty plasmid groups. Conclusion: Our study demonstrates that PKM2 gene silencing suppresses proliferation and promotes apoptosis in LS-147T and SW620 cells.

  17. Communication: spin-orbit splittings in degenerate open-shell states via Mukherjee's multireference coupled-cluster theory: a measure for the coupling contribution.

    Science.gov (United States)

    Mück, Leonie Anna; Gauss, Jürgen

    2012-03-21

    We propose a generally applicable scheme for the computation of spin-orbit (SO) splittings in degenerate open-shell systems using multireference coupled-cluster (MRCC) theory. As a specific method, Mukherjee's version of MRCC (Mk-MRCC) in conjunction with an effective mean-field SO operator is adapted for this purpose. An expression for the SO splittings is derived and implemented using Mk-MRCC analytic derivative techniques. The computed SO splittings are found to be in satisfactory agreement with experimental data. Due to the symmetry properties of the SO operator, SO splittings can be considered a quality measure for the coupling between reference determinants in Jeziorski-Monkhorst based MRCC methods. We thus provide numerical insights into the coupling problem of Mk-MRCC theory. © 2012 American Institute of Physics

  18. TRISO fuel thermal simulations in the LS-VHTR

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Mario C.; Scari, Maria E.; Costa, Antonella L.; Pereira, Claubia; Veloso, Maria A.F., E-mail: marc5663@gmail.com, E-mail: melizabethscari@yahoo.com, E-mail: antonella@nuclear.ufmg.br, E-mail: claubia@nuclear.ufmg.br, E-mail: dora@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Instituto Nacional de Ciência e Tecnologia de Reatores Nucleares Inovadores/CNPq (Brazil)

    2017-07-01

    The liquid-salt-cooled very high-temperature reactor (LS-VHTR) is a reactor that presents very good characteristics in terms of energy production and safety aspects. It uses as fuel the TRISO particles immersed in a graphite matrix with a cylindrical shape called fuel compact, as moderator graphite and as coolant liquid salt Li{sub 2}BeF{sub 4} called Flibe. This work evaluates the thermal hydraulic performance of the heat removal system and the reactor core by performing different simplifications to represent the reactor core and the fuel compact under steady-state conditions, starting the modeling from a single fuel element, until complete the studies with the entire core model developed in the RELAP5-3D code. Two models were considered for representation of the fuel compact, homogeneous and non-homogeneous models, as well as different geometries of the heat structures was considered. The aim to develop several models was to compare the thermal hydraulic characteristics resulting from the construction of a more economical and less discretized model with much more refined models that can lead to more complexes analyzes to representing TRISO effect particles in the fuel compact. The different results found, mainly, for the core temperature distributions are presented and discussed. (author)

  19. Radioiodinated VEGF to image tumor angiogenesis in a LS180 tumor xenograft model

    International Nuclear Information System (INIS)

    Yoshimoto, Mitsuyoshi; Kinuya, Seigo; Kawashima, Atsuhiro; Nishii, Ryuichi; Yokoyama, Kunihiko; Kawai, Keiichi

    2006-01-01

    Introduction: Angiogenesis is essential for tumor growth or metastasis. A method involving noninvasive detection of angiogenic activity in vivo would provide diagnostic information regarding antiangiogenic therapy targeting vascular endothelial cells as well as important insight into the role of vascular endothelial growth factor (VEGF) and its receptor (flt-1 and KDR) system in tumor biology. We evaluated radioiodinated VEGF 121 , which displays high binding affinity for KDR, and VEGF 165 , which possesses high binding affinity for flt-1 and low affinity for KDR, as angiogenesis imaging agents using the LS180 tumor xenograft model. Methods: VEGF 121 and VEGF 165 were labeled with 125 I by the chloramine-T method. Biodistribution was observed in an LS180 human colon cancer xenograft model. Additionally, autoradiographic imaging and immunohistochemical staining of tumors were performed with 125 I-VEGF 121 . Results: 125 I-VEGF 121 and 125 I-VEGF 165 exhibited strong, continuous uptake by tumors and the uterus, an organ characterized by angiogenesis. 125 I-VEGF 121 uptake in tumors was twofold higher than that of 125 I-VEGF 165 (9.12±98 and 4.79±1.08 %ID/g at 2 h, respectively). 125 I-VEGF 121 displayed higher tumor to nontumor (T/N) ratios in most normal organs in comparison with 125 I-VEGF 165 . 125 I-VEGF 121 accumulation in tumors decreased with increasing tumor volume. Autoradiographic and immunohistochemical analyses confirmed that the difference in 125 I-VEGF 121 tumor accumulation correlated with degree of tumor vascularity. Conclusion: Radioiodinated VEGF 121 is a promising tracer for noninvasive delineation of angiogenesis in vivo

  20. tbW anomalous couplings in the Two Higgs Doublet Model

    Energy Technology Data Exchange (ETDEWEB)

    Arhrib, Abdesslam; Jueid, Adil [Département de Mathématiques, Faculté des Sciences et Techniques,Université Abdelmalek Essaadi,B. 416, Tangier (Morocco)

    2016-08-11

    We make a complete one loop calculation of the tbW couplings in the Two Higgs Doublet Model. We evaluate both the anomalous couplings g{sub L} and g{sub R} as well as left handed and right handed component of tbW. The computation is done in the Feynman gauge using the on-shell scheme renormalization for the Standard Model wave functions and parameters. We first show that the relative corrections to these anomalous couplings are rather small in most regions of the parameter space. We then analyze the effects of these anomalous couplings on certain observables such as top quark polarization in single top production through t−channel as well as W{sup ±} boson helicity fractions in top decay.

  1. A fully discrete energy stable scheme for a phase filed moving contact line model with variable densities and viscosities

    KAUST Repository

    Zhu, Guangpu; Chen, Huangxin; Sun, Shuyu; Yao, Jun

    2018-01-01

    In this paper, a fully discrete scheme which considers temporal and spatial discretizations is presented for the coupled Cahn-Hilliard equation in conserved form with the dynamic contact line condition and the Navier-Stokes equation

  2. Mechanisms of Coupled Vibrational Relaxation and Dissociation in Carbon Dioxide.

    Science.gov (United States)

    Armenise, Iole; Kustova, Elena

    2018-05-21

    A complete vibrational state-specific kinetic scheme describing dissociating carbon dioxide mixtures is proposed. CO 2 symmetric, bending and asymmetric vibrations and dissociation-recombination are strongly coupled through inter-mode vibrational energy transfers. Comparative study of state-resolved rate coefficients is carried out; the effect of different transitions may vary considerably with temperature. A non-equilibrium 1-D boundary layer flow typical to hypersonic planetary entry is studied in the state-to-state approach. To assess the sensitivity of fluid-dynamic variables and heat transfer to various vibrational transitions and chemical reactions, corresponding processes are successively included to the kinetic scheme. It is shown that vibrational-translational (VT) transitions in the symmetric and asymmetric modes do not alter the flow and can be neglected whereas the VT 2 exchange in the bending mode is the main channel of vibrational relaxation. Inter-mode vibrational exchanges affect the flow implicitly, through energy redistribution enhancing VT relaxation; the dominating role belongs to near-resonant transitions between symmetric and bending modes as well as between CO molecules and CO 2 asymmetric mode. Strong coupling between VT 2 relaxation and chemical reactions is emphasized. While vibrational distributions and average vibrational energy show strong dependence on the kinetic scheme, the heat flux is more sensitive to chemical reactions.

  3. Numerical Analysis of a Class of THM Coupled Model for Porous Materials

    Science.gov (United States)

    Liu, Tangwei; Zhou, Jingying; Lu, Hongzhi

    2018-01-01

    We consider the coupled models of the Thermo-hydro-mechanical (THM) problem for porous materials which arises in many engineering applications. Firstly, mathematical models of the THM coupled problem for porous materials were discussed. Secondly, for different cases, some numerical difference schemes of coupled model were constructed, respectively. Finally, aassuming that the original water vapour effect is neglectable and that the volume fraction of liquid phase and the solid phase are constants, the nonlinear equations can be reduced to linear equations. The discrete equations corresponding to the linear equations were solved by the Arnodli method.

  4. L.S. Vygotsky's Principle "One Step in Learning — A Hundred Steps in Development": In Search of Evidence

    Directory of Open Access Journals (Sweden)

    V.K. Zaretsky

    2015-10-01

    Full Text Available On the basis of L.S. Vygotsky's published works the paper attempts to trace the dynamics of his concepts of child development and to provide evidence supporting Vygotsky's statement that one step in learning equals a hundred in development, which is one of the key principles of culturalhistorical theory in its application to child development. This statement is put in a row with two other major principles: one arguing that learning precedes development and the other referring to the zone of proximal development. The paper outlines a multivector model of the zone of proximal development as one of the conceptual tools of the reflective and activity approach to helping children overcome learning difficulties and promoting their development. The paper also describes a case study in which an orphan child with a disability received psychological and educational support that obviously contributed to the child's development. It is argued that L.S. Vygotsky's idea of the specific relationship between learning and development has fundamental theoretical and practical implications, in particular, for working with children with special needs

  5. CÁLCULO AUTOMÁTICO DO FATOR TOPOGRÁFICO (LS DA EUPS, NA BACIA DO RIO PARACATU AUTOMATIC CALCULATION OF THE TOPOGRAPHIC FACTOR (LS OF THE USLE, IN THE PARACATU RIVER BASIN

    Directory of Open Access Journals (Sweden)

    Valtercides Cavalcante da Silva

    2007-09-01

    Full Text Available

    Embora a equação universal de perda de solo (EUPS seja amplamente utilizada na predição de perda de solo, é difícil obter certos fatores dessa equação em bacias hidrográficas, como é o caso do fator de comprimento de vertente (fator L. Diante disso, este trabalho objetivou determinar de maneira informatizada (automática, o fator topográfico (LS da EUPS, utilizando para o cálculo do fator L o algoritmo de Desmet & Govers (1996, com o suporte de um Sistema de Informações Geográficas (SIG. Verificou-se a viabilidade do cálculo do fator de comprimento de vertente, na escala de 1:100.000, por meio da metodologia desses autores, que considera o fluxo acumulado.

    Although the Universal Soil Loss Equation (USLE is widely used all over the world in the prediction of soil loss, a few factors of the equation are difficult to obtain, such as the slope length factor (L factor, particularly in watersheds. For this reason, the purpose of the present research was to apply the methodology for automatic calculation of the topographic factor (LS factor using the algorithm developed by Desmet and Govers (1996 which defines the slope length factor (L factor through the Geographic Information System (GIS. It was verified that the slope length factor (L, as developed by Desmet and Govers (1996, which accounts for accumulated flow, showed feasible results.

    KEY-WORDS: USLE; L factor; topographic factor; GIS.

  6. Coupled-channel equations and off-shell transformations in many-body scattering

    International Nuclear Information System (INIS)

    Cattapan, G.; Vanzani, V.

    1977-01-01

    The general structure and the basic features of several many-body coupled-channel integral equations, obtained by means of the channel coupling array device, are studied in a systematic way. Particular attention is paid to the employment of symmetric transition operators. The connection between different formulations has been clarified and the role played by some off-shell transformations for many-body transition operators has been discussed. Specific choices of the coupling scheme are considered and the corresponding coupled equations are compared with similar equations previously derived. Several sets of linear relations between transition operators have also been presented and used in a three-body context to derive uncoupled integral equations with connected kernel

  7. Assessing Intraseasonal Variability Produced by Several Deep Convection Schemes in the NCAR CCM3.6

    Science.gov (United States)

    Maloney, E. D.

    2001-05-01

    The Hack, Zhang/McFarlane, and McRAS convection schemes produce very different simulations of intraseasonal variability in the NCAR CCM3.6. A robust analysis of simulation performance requires an expanded set of diagnostics. The use of only one criterion to analyze model Madden-Julian oscillation (MJO) variability, such as equatorial zonal wind variability, may give a misleading impression of model performance. Schemes that produce strong variability in zonal winds may sometimes lack a corresponding coherent signal in precipitation, suggesting that model convection and the large-scale circulation are not as strongly coupled as observed. The McRAS scheme, which includes a parametrization of unsaturated convective downdrafts, produces the best simulation of intraseasonal variability of the three schemes used. Downdrafts in McRAS create a moister equatorial troposphere, which increases equatorial convection. Composite analysis indicates a strong dependence of model intraseasonal variability on the frictional convergence mechanism, which may also be important in nature. The McRAS simulation has limitations, however. Indian Ocean variability is weak, and anomalous convection extends too far east across the Pacific. The dependence of convection on surface friction is too strong, and causes enhanced MJO convection to be associated with low-level easterly wind perturbations, unlike observed MJO convection. Anomalous vertical advection associated with surface convergence influences model convection by moistening the lower troposphere. Based on the work of Hendon (2000), coupling to an interactive ocean is unlikely to change the performance of the CCM3 with McRAS, due to the phase relationship between anomalous convection and zonal winds. Use of the analysis tools presented here indicates areas for improvement in the parametrization of deep convection by atmospheric GCMs.

  8. Phase diagram of a QED-cavity array coupled via a N-type level scheme

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Jiasen; Rossini, Davide [CNR, NEST, Scuola Normale Superiore and Istituto di Nanoscienze, Pisa (Italy); Fazio, Rosario [CNR, NEST, Scuola Normale Superiore and Istituto di Nanoscienze, Pisa (Italy); National University of Singapore, Center for Quantum Technologies, Singapore (Singapore)

    2015-01-01

    We study the zero-temperature phase diagram of a one-dimensional array of QED cavities where, besides the single-photon hopping, an additional coupling between neighboring cavities is mediated by an N-type four-level system. By varying the relative strength of the various couplings, the array is shown to exhibit a variety of quantum phases including a polaritonic Mott insulator, a density-wave and a superfluid phase. Our results have been obtained by means of numerical density-matrix renormalization group calculations. The phase diagram was obtained by analyzing the energy gaps for the polaritons, as well as through a study of two-point correlation functions. (orig.)

  9. Physical renormalization schemes and asymptotic safety in quantum gravity

    Science.gov (United States)

    Falls, Kevin

    2017-12-01

    The methods of the renormalization group and the ɛ -expansion are applied to quantum gravity revealing the existence of an asymptotically safe fixed point in spacetime dimensions higher than two. To facilitate this, physical renormalization schemes are exploited where the renormalization group flow equations take a form which is independent of the parameterisation of the physical degrees of freedom (i.e. the gauge fixing condition and the choice of field variables). Instead the flow equation depends on the anomalous dimensions of reference observables. In the presence of spacetime boundaries we find that the required balance between the Einstein-Hilbert action and Gibbons-Hawking-York boundary term is preserved by the beta functions. Exploiting the ɛ -expansion near two dimensions we consider Einstein gravity coupled to matter. Scheme independence is generically obscured by the loop-expansion due to breaking of two-dimensional Weyl invariance. In schemes which preserve two-dimensional Weyl invariance we avoid the loop expansion and find a unique ultraviolet (UV) fixed point. At this fixed point the anomalous dimensions are large and one must resum all loop orders to obtain the critical exponents. Performing the resummation a set of universal scaling dimensions are found. These scaling dimensions show that only a finite number of matter interactions are relevant. This is a strong indication that quantum gravity is renormalizable.

  10. Inductively coupled plasma-mass spectrometry: an initial assessment of the VG isotopes Plasmaquad

    International Nuclear Information System (INIS)

    Brown, R.M.; Pickford, C.J.

    1985-04-01

    The Chemical Analysis Group has been approached by a British Scientific instrument maker regarding the possibility of the group participating in a Department of Trade and Industry sponsored scheme whereby we would have a 12 month period to assess the advantages and disadvantages of a new analytical technique, Inductively Coupled Plasma-Mass Spectrometry. This report details our initial assessment of the instrument, carried out in order to decide whether to participate in the scheme. We have attempted to discover whether the instrument meets the claims made of it in advertising literature, and have attempted to compare the technique with another, proven technique, Inductively Coupled Plasma - Optical Emission Spectroscopy. The Plasmaquad offers excellent sensitivity for almost all of the elements of the periodic table, giving a distinct improvement over the Chemical Analysis Group's present capabilities for many elements. The isotope ratio measuring ability is important, as the Group has no such capability at the moment and a demand for this type of measurement is foreseen. Our conclusions, while inevitably somewhat subjective, form the basis for recommending Harwell to participate in the scheme. (author)

  11. The intellectual capacity of patients with Laron syndrome (LS) differs with various molecular defects of the growth hormone receptor gene. Correlation with CNS abnormalities.

    Science.gov (United States)

    Shevah, O; Kornreich, L; Galatzer, A; Laron, Z

    2005-12-01

    The correlation between the molecular defects of the GH receptor (R), psychosocial development and brain abnormalities were evaluated in 10 patients with Laron syndrome (LS), in whom all data were available. The findings revealed that the intelligence quotient (IQ) and abnormalities in the brain of the patients with LS differ with various molecular defects of the GH-receptor. The most severe mental deficits and brain pathology occurred in patients with 3, 5, 6 exon deletion. Patients with point mutations in exons 2, 4 and 7 presented various degrees of medium to mild CNS abnormalities that correlated with the IQ. Notably, the patient with the E180 splice mutation in exon 6 had a normal IQ, which fits the report on normal IQ in a large Ecuadorian cohort with the same mutation. This is the first report to support a correlation between IQ, brain abnormalities and localization of the molecular defects in the GH-R gene. As all patients with LS are IGF-I-deficient, it must be assumed that other as yet unknown factors related to the molecular defects in the GH-R are the major cause of the differences in intellect and brain abnormalities.

  12. Mode Dynamics in the Bragg FEL Based on Coupling of Propagating and Trapped Waves

    CERN Document Server

    Ginzburg, N S; Peskov, N Yu; Rozental, R M; Sergeev, A; Zaslavsky, V Yu

    2005-01-01

    A novel Bragg FEL scheme is discussed in which an electron beam synchronously interacts with a propagating wave, and the latter is coupled to a quasi cut-off mode. This coupling is realized by either helical or asimuthally symmetric corrugation of the waveguide walls. The quasi cut-off mode provides feedback in the system leading to self-excitation of the whole system while the efficiency in steady-state regime of generation is almost completely determined by the propagating mode, synchronous to the beam. Analysis based on averaged time domain approach as well as on direct PIC code simulation shows that the efficiency of such a device in the single mode single frequency regime can be rather high. The main advantage of the novel Bragg resonator is provision of higher selectivity over transverse index than traditional scheme of Bragg FEL. The cold microwave testing of the Bragg structure based on coupling of propagating and trapped waves in the Ka band demonstrated a good agreement with theoretical consideratio...

  13. Reduction of plyatomic ion interferences in indictively coupled plasma mass spectrometry with cryogenic desolvation

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Luis C. [Iowa State Univ., Ames, IA (United States)

    1993-09-01

    A desolvation scheme for introducing aqueous and organic samples into an argon inductively coupled plasma is described; the aerosol generated by nebulizer is heated (+140 C) and cooled (-80 C) repeatedly, and the dried aerosol is then injected into the mass spectrometer. Polyatomic ions are greatly suppressed. This scheme was validated with analysis of seawater and urine reference samples. Finally, the removal of organic solvents by cryogenic desolvation was studied.

  14. Tunable optical nonreciprocity and a phonon-photon router in an optomechanical system with coupled mechanical and optical modes

    Science.gov (United States)

    Li, Guolong; Xiao, Xiao; Li, Yong; Wang, Xiaoguang

    2018-02-01

    We propose a multimode optomechanical system to realize tunable optical nonreciprocity that has the prospect of making an optical diode for information technology. The proposed model consists of two subsystems, each of which contains two optical cavities, injected with a classical field and a quantum signal via a 50:50 beam splitter, and a mechanical oscillator, coupled to both cavities via optomechanical coupling. Meanwhile two cavities and an oscillator in a subsystem are respectively coupled to their corresponding cavities and an oscillator in the other subsystem. Our scheme yields nonreciprocal effects at different frequencies with opposite directions, but each effective linear optomechanical coupling can be controlled by an independent classical one-frequency pump. With this setup one is able to apply quantum states with large fluctuations, which extends the scope of applicable quantum states, and exploit the independence of paths. Moreover, the optimal frequencies for nonreciprocal effects can be controlled by adjusting the relevant parameters. We also exhibit the path switching of two directions, from a mechanical input to two optical output channels, via tuning the signal frequency. In experiment, the considered scheme can be tuned to reach small damping rates of the oscillators relative to those of the cavities, which is more practical and requires less power than in previous schemes.

  15. Scalable quantum memory in the ultrastrong coupling regime.

    Science.gov (United States)

    Kyaw, T H; Felicetti, S; Romero, G; Solano, E; Kwek, L-C

    2015-03-02

    Circuit quantum electrodynamics, consisting of superconducting artificial atoms coupled to on-chip resonators, represents a prime candidate to implement the scalable quantum computing architecture because of the presence of good tunability and controllability. Furthermore, recent advances have pushed the technology towards the ultrastrong coupling regime of light-matter interaction, where the qubit-resonator coupling strength reaches a considerable fraction of the resonator frequency. Here, we propose a qubit-resonator system operating in that regime, as a quantum memory device and study the storage and retrieval of quantum information in and from the Z2 parity-protected quantum memory, within experimentally feasible schemes. We are also convinced that our proposal might pave a way to realize a scalable quantum random-access memory due to its fast storage and readout performances.

  16. Validation of Transtek LS808-B for self/home measurement according to the European Society of Hypertension International Protocol revision 2010.

    Science.gov (United States)

    Liu, Zhong Hua; Liu, Xian Yue; Wu, Wen Jun

    2016-12-01

    This study aimed to evaluate the accuracy of Transtek LS808-B according to the European Society of Hypertension International Protocol revision 2010 (ESH-IP2010). A total of 33 adult individuals (19 men and 14 women, mean age 46.8±15.8 years) were recruited; their systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using the mercury sphygmomanometer and Transtek LS808-B. A total of 99 pairs of measurements were obtained from these 33 participants for comparison in two parts with three grading phases. All the validation requirements were fulfilled. The number of absolute difference between the tested device and the observers within 5, 10, and 15 mmHg was 73, 94, and 98 for SBP and 78, 94, and 99 for DBP, respectively. The mean±SD of the device-observer difference was 0.5±4.4 mmHg for SBP and 0.2±4.1 mmHg for DBP. The number of participants with two or three device-observer differences within 5 mmHg was 24 for SBP and 27 for DBP. In addition, two of the participants had no device-observer difference within 5 mmHg for SBP and one of the participants had the same for DBP. Transtek LS808-B has passed all phases of ESH-IP 2010, and hence can be recommended for self/home measurement in adult populations.

  17. Electrical and Quench Performance of the First MICE Coupling Coil

    International Nuclear Information System (INIS)

    Tartaglia, M. A.; Carcagno, R.; Makulski, A.; Nogiec, Jerzy; Orris, D.; Pilipenko, R.; Sylvester, C.; Caspi, S.; Pan, H.; Prestemon, S.; Virostek, S.

    2014-01-01

    The first MICE Coupling Coil has been tested in a conduction-cooled environment in the new Solenoid Test Facility at Fermilab. We present an overview of the power and quench protection scheme, and report on the electrical and quench performance results obtained during cold power tests of the magnet

  18. A DPL model of photo-thermal interaction in an infinite semiconductor material containing a spherical hole

    Science.gov (United States)

    Hobiny, Aatef D.; Abbas, Ibrahim A.

    2018-01-01

    The dual phase lag (DPL) heat transfer model is applied to study the photo-thermal interaction in an infinite semiconductor medium containing a spherical hole. The inner surface of the cavity was traction free and loaded thermally by pulse heat flux. By using the eigenvalue approach methodology and Laplace's transform, the physical variable solutions are obtained analytically. The numerical computations for the silicon-like semiconductor material are obtained. The comparison among the theories, i.e., dual phase lag (DPL), Lord and Shulman's (LS) and the classically coupled thermoelastic (CT) theory is presented graphically. The results further show that the analytical scheme can overcome mathematical problems by analyzing these problems.

  19. 1ST-ORDER NONADIABATIC COUPLING MATRIX-ELEMENTS FROM MULTICONFIGURATIONAL SELF-CONSISTENT-FIELD RESPONSE THEORY

    DEFF Research Database (Denmark)

    Bak, Keld L.; Jørgensen, Poul; Jensen, H.J.A.

    1992-01-01

    A new scheme for obtaining first-order nonadiabatic coupling matrix elements (FO-NACME) for multiconfigurational self-consistent-field (MCSCF) wave functions is presented. The FO-NACME are evaluated from residues of linear response functions. The residues involve the geometrical response of a ref......A new scheme for obtaining first-order nonadiabatic coupling matrix elements (FO-NACME) for multiconfigurational self-consistent-field (MCSCF) wave functions is presented. The FO-NACME are evaluated from residues of linear response functions. The residues involve the geometrical response...... to the full configuration interaction limit. Comparisons are made with state-averaged MCSCF results for MgH2 and finite-difference configuration interaction by perturbation with multiconfigurational zeroth-order wave function reflected by interactive process (CIPSI) results for BH....

  20. Effects of Injection Scheme on Rotating Detonation Engine Operation

    Science.gov (United States)

    Chacon, Fabian; Duvall, James; Gamba, Mirko

    2017-11-01

    In this work, we experimentally investigate the operation and performance characteristics of a rotating detonation engine (RDE) operated with different fuel injection schemes and operating conditions. In particular, we investigate the detonation and operation characteristics produced with an axial flow injector configuration and semi-impinging injector configurations. These are compared to the characteristics produced with a canonical radial injection system (AFRL injector). Each type produces a different flowfield and mixture distribution, leading to a different detonation initiation, injector dynamic response, and combustor pressure rise. By using a combination of diagnostics, we quantify the pressure loses and gains in the system, the ability to maintain detonation over a range of operating points, and the coupling between the detonation and the air/fuel feed lines. We particularly focus on how this coupling affects both the stability and the performance of the detonation wave. This work is supported by the DOE/UTSR program under project DE-FE0025315.

  1. An asymptotic preserving multidimensional ALE method for a system of two compressible flows coupled with friction

    Science.gov (United States)

    Del Pino, S.; Labourasse, E.; Morel, G.

    2018-06-01

    We present a multidimensional asymptotic preserving scheme for the approximation of a mixture of compressible flows. Fluids are modelled by two Euler systems of equations coupled with a friction term. The asymptotic preserving property is mandatory for this kind of model, to derive a scheme that behaves well in all regimes (i.e. whatever the friction parameter value is). The method we propose is defined in ALE coordinates, using a Lagrange plus remap approach. This imposes a multidimensional definition and analysis of the scheme.

  2. Supercurrent and the Adler-Bardeen theorem in coupled supersymmetric Yang-Mills theories

    International Nuclear Information System (INIS)

    Ensign, P.; Mahanthappa, K.T.

    1987-01-01

    We construct the supercurrent and a supersymmetric current which satisfies the Adler-Bardeen theorem in supersymmetric Yang-Mills theory coupled to non-self-interacting chiral matter. Using the formulation recently developed by Grisaru, Milewski, and Zanon, supersymmetry and gauge invariance are maintained with supersymmetric background-field theory and regularization by dimensional reduction. We verify the finiteness of the supercurrent to one loop, and the Adler-Bardeen theorem to two loops by explicit calculations in the minimal-subtraction scheme. We then demonstrate the subtraction-scheme independence of the one-loop Adler-Bardeen anomaly and prove the existence of a subtraction scheme in which the Adler-Bardeen theorem is satisfied to all orders in perturbation theory

  3. Terahertz wave generation in coupled quantum dots

    International Nuclear Information System (INIS)

    Ma Yu-Rong; Guo Shi-Fang; Duan Su-Qing

    2012-01-01

    Based on coupled quantum dots, we present an interesting optical effect in a four-level loop coupled system. Both the two upper levels and the two lower levels are designed to be almost degenerate, which induces a considerable dipole moment. The terahertz wave is obtained from the low-frequency component of the photon emission spectrum. The frequency of the terahertz wave can be controlled by tuning the energy levels via designing the nanostructure appropriately or tuning the driving laser field. A terahertz wave with adjustable frequency and considerable intensity (100 times higher than that of the Rayleigh line) can be obtained. It provides an effective scheme for a terahertz source. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  4. Increase in effectiveness of low frequency acoustic liners by use of coupled Helmholtz resonators

    Science.gov (United States)

    Dean, L. W.

    1977-01-01

    Coupling of Helmholtz resonators in a low-frequency absorber array was studied as a means for increasing the effectiveness for absorbing low-frequency core engine noise. The equations for the impedance of the coupled-resonator systems were developed in terms of uncoupled-resonator parameters, and the predicted impedance for a parallel-coupled scheme is shown to compare favorably with measurements from a test model. In addition, attenuation measurements made in a flow duct on test coupled-resonator panels are shown to compare favorably with predicted values. Finally, the parallel-coupled concept is shown to give significantly more attenuation than that of a typical uncoupled resonator array of the same total volume.

  5. BCS superconductivity for weakly coupled clusters

    International Nuclear Information System (INIS)

    Friedel, J.

    1992-01-01

    BCS superconductivity is expected to have fairly high critical temperatures when clusters of moderate sizes are weakly coupled to form a crystal. This remark extends to quasi zerodimensional cases, a remark initially made by Labbe for quasi one-dimensional ones and by Hirsch, Bok and Labbe for quasi twodimensional ones. Possible applications are envisaged for twodimensional clusters (fullerene) or threedimensional ones (metal clusters, Chevrel phases). Conditions for optimal applicability of the scheme are somewhat restricted. (orig.)

  6. Gamma–Gamma Absorption in the γ-ray Binary System PSR B1259-63/LS 2883

    Energy Technology Data Exchange (ETDEWEB)

    Sushch, Iurii [Centre for Space Research, North-West University, 2520 Potcheftroom (South Africa); Van Soelen, Brian, E-mail: iurii.sushch@desy.de, E-mail: vansoelenb@ufs.ac.za [Department of Physics, University of the Free State, 9300 Bloemfontein (South Africa)

    2017-03-10

    The observed TeV light curve from the γ -ray binary PSR B1259-63/LS 2883 shows a decrease in the flux at periastron that has not been fully explained by emission mechanisms alone. This observed decrease can, however, be explained by γγ absorption due to the stellar and disk photons. We calculate the γγ absorption in PSR B1259-63/LS 2883 taking into account photons from both the circumstellar disk and star, assuming that the γ -rays originate at the position of the pulsar. The γγ absorption due to the circumstellar disk photons produces a ≈14% decrease in the flux, and there is a total decrease of ≈52% (>1 TeV) within a few days before periastron, accompanied by a hardening of the γ -ray photon index. While the γγ absorption alone is not sufficient to explain the full complexity of the H.E.S.S. γ -ray light curve, it results in a significant decrease in the predicted flux, which is coincident with the observed decrease. In addition, we have calculated an upper limit on the γγ absorption, assuming that the emission is produced at the apex of the bow shock. Future observations with CTA during the 2021 periastron passage may be able to confine the location of the emission based on the degree of γγ absorption, as well as measure the hardening of the spectrum around periastron.

  7. Effects induced by ICRF waves on various confinement schemes in Tore Supra

    International Nuclear Information System (INIS)

    Saoutic, B.

    1995-01-01

    The 1993-94 experimental campaign has seen a significant increase of the application of waves in the ion cyclotron range of frequency on Tore Supra. Ion cyclotron resonant heating has been applied to plasmas with strongly radiating layers, pellet-enhanced performance and lower hybrid enhanced performance. Initial experiments on direct coupling of the fast magnetosonic wave to the electrons have demonstrated coupling up to 5 MW to the plasma and have demonstrated an efficient electron heating in these discharges. A significant bootstrap current fraction is observed. This heating scheme leads to a stationary improvement in energy confinement, with implications for the Rebut-Lallia-Watkins local transport model. Finally, preliminary experiments on antenna phasing have shown clear evidence of fast wave current drive. (author) 25 refs.; 9 figs

  8. Causes and Consequences of a Father's Child Leave: Evidence from a Reform of Leave Schemes

    DEFF Research Database (Denmark)

    Nielsen, Helena Skyt

    are the most progressive when it comes to family-friendly policies. An extensive reform of child leave schemes in Denmark affected couples differently depending on whether the parents where employed in the same or in different parts of the public sector. Based on a difference-in-differences strategy, I find...... that economic incentives are very important for intra-household leave-sharing. Increasing the couples' after tax income by $9 per day of leave which is transferred from the mother to the father is found to lead to a one day transfer. This corresponds to a supply elasticity close to unity....

  9. Discrete memory schemes for finite strain thermoplasticity and application to shape memory alloys

    International Nuclear Information System (INIS)

    Favier, D.; Guelin, P.; Pegon, P.; Nowacki, W.K.

    1987-01-01

    A theory of finite strain plasticity has been proposed: The scheme of pure hysteresis with mixed transport has been extended to the case of non-rotational kinematics. Secondly, the simple shear case has been studied, taking into account Drucker's recent analysis regarding the 'appropriate simple idealizations for finite plasticity'. Illustrations are provided for general stress/strain paths. Also a new theory of isotropic hyperelasticity has been proposed. The 'reversible' relative Cauchy stress tensor (of type (1,1) and weight one) is defined in the dragged along coordinates as a tensorial isotropic function of the Almansi tensor and of its invariants (through the partial derivatives of the actual scalar density of elastic energy per unit extent of dragged along coordinates). The correspondance between strain and stress paths is then defined in a general form which is particularly convenient for the study of first order effects, limit behaviours, coupling and second order effects. Illustrations are provided. The addition of the pure hysteresis stress contribution σ a and of the reversible contribution σ rev leads to a scheme of 'superelasticity' departure to obtain a provisional scheme of shape memory effects. Some remarks are given regarding some of the possible generalizations of the scheme. (orig./GL)

  10. Coupled electrostatic-elastic analysis for topology optimization using material interpolation

    International Nuclear Information System (INIS)

    Alwan, A; Ananthasuresh, G K

    2006-01-01

    In this paper, we present a novel analytical formulation for the coupled partial differential equations governing electrostatically actuated constrained elastic structures of inhomogeneous material composition. We also present a computationally efficient numerical framework for solving the coupled equations over a reference domain with a fixed finiteelement mesh. This serves two purposes: (i) a series of problems with varying geometries and piece-wise homogeneous and/or inhomogeneous material distribution can be solved with a single pre-processing step (ii) topology optimization methods can be easily implemented by interpolating the material at each point in the reference domain from a void to a dielectric or a conductor. This is attained by considering the steady-state electrical current conduction equation with a 'leaky capacitor' model instead of the usual electrostatic equation. This formulation is amenable for both static and transient problems in the elastic domain coupled with the quasi-electrostatic electric field. The procedure is numerically implemented on the COMSOL Multiphysics (registered) platform using the weak variational form of the governing equations. Examples have been presented to show the accuracy and versatility of the scheme. The accuracy of the scheme is validated for the special case of piece-wise homogeneous material in the limit of the leaky-capacitor model approaching the ideal case

  11. Colour schemes

    DEFF Research Database (Denmark)

    van Leeuwen, Theo

    2013-01-01

    This chapter presents a framework for analysing colour schemes based on a parametric approach that includes not only hue, value and saturation, but also purity, transparency, luminosity, luminescence, lustre, modulation and differentiation.......This chapter presents a framework for analysing colour schemes based on a parametric approach that includes not only hue, value and saturation, but also purity, transparency, luminosity, luminescence, lustre, modulation and differentiation....

  12. Initial conditions and ENSO prediction using a coupled ocean-atmosphere model

    Science.gov (United States)

    Larow, T. E.; Krishnamurti, T. N.

    1998-01-01

    A coupled ocean-atmosphere initialization scheme using Newtonian relaxation has been developed for the Florida State University coupled ocean-atmosphere global general circulation model. The initialization scheme is used to initialize the coupled model for seasonal forecasting the boreal summers of 1987 and 1988. The atmosphere model is a modified version of the Florida State University global spectral model, resolution T-42. The ocean general circulation model consists of a slightly modified version of the Hamburg's climate group model described in Latif (1987) and Latif et al. (1993). The coupling is synchronous with information exchanged every two model hours. Using ECMWF atmospheric daily analysis and observed monthly mean SSTs, two, 1-year, time-dependent, Newtonian relaxation were performed using the coupled model prior to conducting the seasonal forecasts. The coupled initializations were conducted from 1 June 1986 to 1 June 1987 and from 1 June 1987 to 1 June 1988. Newtonian relaxation was applied to the prognostic atmospheric vorticity, divergence, temperature and dew point depression equations. In the ocean model the relaxation was applied to the surface temperature. Two, 10-member ensemble integrations were conducted to examine the impact of the coupled initialization on the seasonal forecasts. The initial conditions used for the ensembles are the ocean's final state after the initialization and the atmospheric initial conditions are ECMWF analysis. Examination of the SST root mean square error and anomaly correlations between observed and forecasted SSTs in the Niño-3 and Niño-4 regions for the 2 seasonal forecasts, show closer agreement between the initialized forecast than two, 10-member non-initialized ensemble forecasts. The main conclusion here is that a single forecast with the coupled initialization outperforms, in SST anomaly prediction, against each of the control forecasts (members of the ensemble) which do not include such an initialization

  13. Quantum Simulation of the Ultrastrong-Coupling Dynamics in Circuit Quantum Electrodynamics

    Directory of Open Access Journals (Sweden)

    D. Ballester

    2012-05-01

    Full Text Available We propose a method to get experimental access to the physics of the ultrastrong- and deep-strong-coupling regimes of light-matter interaction through the quantum simulation of their dynamics in standard circuit QED. The method makes use of a two-tone driving scheme, using state-of-the-art circuit-QED technology, and can be easily extended to general cavity-QED setups. We provide examples of ultrastrong- and deep-strong-coupling quantum effects that would be otherwise inaccessible.

  14. Selective Linear or Quadratic Optomechanical Coupling via Measurement

    Directory of Open Access Journals (Sweden)

    Michael R. Vanner

    2011-11-01

    Full Text Available The ability to engineer both linear and nonlinear coupling with a mechanical resonator is an important goal for the preparation and investigation of macroscopic mechanical quantum behavior. In this work, a measurement based scheme is presented where linear or square mechanical-displacement coupling can be achieved using the optomechanical interaction that is linearly proportional to the mechanical position. The resulting square-displacement measurement strength is compared to that attainable in the dispersive case that has a direct interaction with the mechanical-displacement squared. An experimental protocol and parameter set are discussed for the generation and observation of non-Gaussian states of motion of the mechanical element.

  15. MIMO to LS-MIMO: A road to realization of 5G

    Science.gov (United States)

    Koppati, Naveena; Pavani, K.; Sharma, Dinesh; Sharma, Purnima K.

    2017-07-01

    MIMO means multiple inputs multiple outputs. As it refers MIMO is a RF technology used in many new technologies these days to increase link capacity and spectral efficiency. MIMO is used in Wi-Fi, LTE, 4G, 5G and other wireless technologies. This paper describes the earlier history of MIMO-OFDM and the antenna beam forming development in MIMO and types of MIMO. Also this treatise describes several decoding algorithms. The MIMO combined with OFDM increases the channel capacity. But the main problem is in estimating the transmitted signal from the received signal. So the channel knowledge is to be known in estimating the channel capacity. The advancement in MIMO-OFDM is Massive MIMO which is beneficial in providing additional data capacity in the increased traffic environment is described. In this memoir various application scenarios of LS-MIMO which increases the capacity are discussed.

  16. Large-eddy simulation/Reynolds-averaged Navier-Stokes hybrid schemes for high speed flows

    Science.gov (United States)

    Xiao, Xudong

    Three LES/RANS hybrid schemes have been proposed for the prediction of high speed separated flows. Each method couples the k-zeta (Enstrophy) BANS model with an LES subgrid scale one-equation model by using a blending function that is coordinate system independent. Two of these functions are based on turbulence dissipation length scale and grid size, while the third one has no explicit dependence on the grid. To implement the LES/RANS hybrid schemes, a new rescaling-reintroducing method is used to generate time-dependent turbulent inflow conditions. The hybrid schemes have been tested on a Mach 2.88 flow over 25 degree compression-expansion ramp and a Mach 2.79 flow over 20 degree compression ramp. A special computation procedure has been designed to prevent the separation zone from expanding upstream to the recycle-plane. The code is parallelized using Message Passing Interface (MPI) and is optimized for running on IBM-SP3 parallel machine. The scheme was validated first for a flat plate. It was shown that the blending function has to be monotonic to prevent the RANS region from appearing in the LES region. In the 25 deg ramp case, the hybrid schemes provided better agreement with experiment in the recovery region. Grid refinement studies demonstrated the importance of using a grid independent blend function and further improvement with experiment in the recovery region. In the 20 deg ramp case, with a relatively finer grid, the hybrid scheme characterized by grid independent blending function well predicted the flow field in both the separation region and the recovery region. Therefore, with "appropriately" fine grid, current hybrid schemes are promising for the simulation of shock wave/boundary layer interaction problems.

  17. An Efficient, Semi-implicit Pressure-based Scheme Employing a High-resolution Finitie Element Method for Simulating Transient and Steady, Inviscid and Viscous, Compressible Flows on Unstructured Grids

    Energy Technology Data Exchange (ETDEWEB)

    Richard C. Martineau; Ray A. Berry

    2003-04-01

    A new semi-implicit pressure-based Computational Fluid Dynamics (CFD) scheme for simulating a wide range of transient and steady, inviscid and viscous compressible flow on unstructured finite elements is presented here. This new CFD scheme, termed the PCICEFEM (Pressure-Corrected ICE-Finite Element Method) scheme, is composed of three computational phases, an explicit predictor, an elliptic pressure Poisson solution, and a semiimplicit pressure-correction of the flow variables. The PCICE-FEM scheme is capable of second-order temporal accuracy by incorporating a combination of a time-weighted form of the two-step Taylor-Galerkin Finite Element Method scheme as an explicit predictor for the balance of momentum equations and the finite element form of a time-weighted trapezoid rule method for the semi-implicit form of the governing hydrodynamic equations. Second-order spatial accuracy is accomplished by linear unstructured finite element discretization. The PCICE-FEM scheme employs Flux-Corrected Transport as a high-resolution filter for shock capturing. The scheme is capable of simulating flows from the nearly incompressible to the high supersonic flow regimes. The PCICE-FEM scheme represents an advancement in mass-momentum coupled, pressurebased schemes. The governing hydrodynamic equations for this scheme are the conservative form of the balance of momentum equations (Navier-Stokes), mass conservation equation, and total energy equation. An operator splitting process is performed along explicit and implicit operators of the semi-implicit governing equations to render the PCICE-FEM scheme in the class of predictor-corrector schemes. The complete set of semi-implicit governing equations in the PCICE-FEM scheme are cast in this form, an explicit predictor phase and a semi-implicit pressure-correction phase with the elliptic pressure Poisson solution coupling the predictor-corrector phases. The result of this predictor-corrector formulation is that the pressure Poisson

  18. Vortices in spin-orbit-coupled Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Radic, J.; Sedrakyan, T. A.; Galitski, V.; Spielman, I. B.

    2011-01-01

    Realistic methods to create vortices in spin-orbit-coupled Bose-Einstein condensates are discussed. It is shown that, contrary to common intuition, rotation of the trap containing a spin-orbit condensate does not lead to an equilibrium state with static vortex structures but gives rise instead to nonequilibrium behavior described by an intrinsically time-dependent Hamiltonian. We propose here the following alternative methods to induce thermodynamically stable static vortex configurations: (i) to rotate both the lasers and the anisotropic trap and (ii) to impose a synthetic Abelian field on top of synthetic spin-orbit interactions. Effective Hamiltonians for spin-orbit condensates under such perturbations are derived for most currently known realistic laser schemes that induce synthetic spin-orbit couplings. The Gross-Pitaevskii equation is solved for several experimentally relevant regimes. The new interesting effects include spatial separation of left- and right-moving spin-orbit condensates, the appearance of unusual vortex arrangements, and parity effects in vortex nucleation where the topological excitations are predicted to appear in pairs. All these phenomena are shown to be highly nonuniversal and depend strongly on a specific laser scheme and system parameters.

  19. Studying the gradient flow coupling in the Schroedinger functional

    Energy Technology Data Exchange (ETDEWEB)

    Fritzsch, P. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Ramos, A. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC

    2013-08-15

    We discuss the setup and features of a new definition of the running coupling in the Schroedinger functional scheme based on the gradient flow. Its suitability for a precise continuum limit in QCD is demonstrated on a set of N{sub f}=2 gauge field ensembles in a physical volume of L{proportional_to}0.4 fm.

  20. Dislocation Coupling-Induced Transition of Synchronization in Two-Layer Neuronal Networks

    International Nuclear Information System (INIS)

    Qin Hui-Xin; Ma Jun; Wang Chun-Ni; Jin Wu-Yin

    2014-01-01

    The mutual coupling between neurons in a realistic neuronal system is much complex, and a two-layer neuronal network is designed to investigate the transition of electric activities of neurons. The Hindmarsh—Rose neuron model is used to describe the local dynamics of each neuron, and neurons in the two-layer networks are coupled in dislocated type. The coupling intensity between two-layer networks, and the coupling ratio (Pro), which defines the percentage involved in the coupling in each layer, are changed to observe the synchronization transition of collective behaviors in the two-layer networks. It is found that the two-layer networks of neurons becomes synchronized with increasing the coupling intensity and coupling ratio (Pro) beyond certain thresholds. An ordered wave in the first layer is useful to wake up the rest state in the second layer, or suppress the spatiotemporal state in the second layer under coupling by generating target wave or spiral waves. And the scheme of dislocation coupling can be used to suppress spatiotemporal chaos and excite quiescent neurons. (interdisciplinary physics and related areas of science and technology)