WorldWideScience

Sample records for high coupling degree

  1. Degree of coupling in high-rise mixed shear walls structures

    Indian Academy of Sciences (India)

    A simple method of analysis is presented to determine the influence of single shear walls (SSW) on the degree of coupling DoC and on the peak shear demand PSD for beams of coupled shear walls (CSW) in mixed shear wall structures (MSW). Non-coupled lateral load resisting structures such as singular planar walls and ...

  2. Low-energy coupling of individual and collective degrees of freedom: a general microscopic approach

    International Nuclear Information System (INIS)

    Quentin, P.; Meyer, M.

    1988-01-01

    A general microscopic approach of low energy coupling of individual and collective degrees of freedom is presented. The ingredients of a Bohr-Mottelson unified model description are determined consistently from the Skyrme SIII effective interaction, through the adiabatic limit of the time-dependent Hartree-Fock-Bogoliubov approximation. Three specific aspects will be mostly developed: i) the effect of pairing correlations on adiabatic mass parameters and collective dynamics; ii) a consistent coupling of collective and individual degrees of freedom to describe odd nuclei; iii) a study of spectroscopic data in odd-odd nuclei as a test of effective nucleon-nucleon interactions. (author)

  3. Degree of coupling in high-rise mixed shear walls structures

    Indian Academy of Sciences (India)

    assessment of the structural behaviour of coupled shear wall bents in mixed shear wall ... efficient lateral load resisting system against wind and earthquake effects. .... can be obtained from the second derivative of equation (11) which must be ...

  4. Chaos and routes to chaos in coupled Duffing oscillators with multiple degrees of freedom

    International Nuclear Information System (INIS)

    Musielak, D.E.; Musielak, Z.E.; Benner, J.W.

    2005-01-01

    New results are reported on the routes to chaos in increasingly complex Duffing oscillator systems, which are formed by coupling several oscillators, thereby increasing the number of degrees of freedom. Other forms of increasing system complexity through distributed excitation, different forcing function phasing, different excitation frequency ratios, and higher order coupling are also studied. Changes in the quantitative aspects of the chaotic regions and in the routes to chaos of complex Duffing systems are investigated by performing numerical simulations. It is shown that the number of chaotic regions in these systems is significantly reduced when compared to the original Duffing system, and that crisis replaces period doubling as the dominant route to chaos when the number of degrees of freedom is increased. A new discovered phenomenon is that chaos emerges in the symmetrically and asymmetrically coupled Duffing oscillators only after the quasi-periodic torus breaks down through a 3-periodic and 2-periodic window, respectively

  5. Coupling dynamic modeling and simulation of three-degree-of-freedom micromanipulator based on piezoelectric ceramic of fuzzy PID

    Science.gov (United States)

    Li, Dongjie; Fu, Yu; Yang, Liu

    2017-08-01

    For further research on the microparticles trajectory in the process of micromanipulation, the paper modeled on the coupling dynamic of three-degree-of-freedom micromanipulator which is based on piezoelectric ceramic. In the micromanipulation, the transformation of certain movement direction can generate a corresponding change in the coupling in three-degree-of-freedom micromanipulator movement, the fuzzy PID method was adopted by the control system of this study, and the modeling analysis was performed on the control system. After completing the above modeling, the simulation model is built by the MATLAB Simulink software. The simulation output results are basically in accordance with the actual trajectory, which achieve the successful research purposes of coupling dynamics model for three-degree-of-freedom micromanipulator and application of fuzzy PID method.

  6. High precision NC lathe feeding system rigid-flexible coupling model reduction technology

    Science.gov (United States)

    Xuan, He; Hua, Qingsong; Cheng, Lianjun; Zhang, Hongxin; Zhao, Qinghai; Mao, Xinkai

    2017-08-01

    This paper proposes the use of dynamic substructure method of reduction of order to achieve effective reduction of feed system for high precision NC lathe feeding system rigid-flexible coupling model, namely the use of ADAMS to establish the rigid flexible coupling simulation model of high precision NC lathe, and then the vibration simulation of the period by using the FD 3D damper is very effective for feed system of bolt connection reduction of multi degree of freedom model. The vibration simulation calculation is more accurate, more quickly.

  7. High degree modes and instrumental effects

    Energy Technology Data Exchange (ETDEWEB)

    Korzennik, S G [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Rabello-Soares, M C; Schou, J [Stanford University, Stanford, CA (United States)], E-mail: skorzennik@cfa.harvard.edu

    2008-10-15

    Full-disk observations taken with the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO) spacecraft, or the upgraded Global Oscillations Network Group (GONG) instruments, have enough spatial resolution to resolve modes up to {iota} = 1000 if not {iota} = 1500. The inclusion of such high-degree modes (i.e., {iota} {<=} 1000) improves dramatically inferences near the surface. Unfortunately, observational and instrumental effects cause the characterization of high degree modes to be quite complicated. Indeed, the characteristics of the solar acoustic spectrum are such that, for a given order, mode lifetimes get shorter and spatial leaks get closer in frequency as the degree of a mode increases. A direct consequence of this property is that individual modes are resolved only at low and intermediate degrees. At high degrees the individual modes blend into ridges and the power distribution of the ridge defines the ridge central frequency, masking the underlying mode frequency. An accurate model of the amplitude of the peaks that contribute to the ridge power distribution is needed to recover the underlying mode frequency from fitting the ridge. We present a detailed discussion of the modeling of the ridge power distribution, and the contribution of the various observational and instrumental effects on the spatial leakage, in the context of the MDI instrument. We have constructed a physically motivated model (rather than an ad hoc correction scheme) that results in a methodology that can produce unbiased estimates of high-degree modes. This requires that the instrumental characteristics are well understood, a task that has turned out to pose a major challenge. We also present our latest results, where most of the known instrumental and observational effects that affect specifically high-degree modes were removed. These new results allow us to focus our attention on changes with solar activity. Finally, we present variations of mode

  8. Phase-dependent dynamic potential of magnetically coupled two-degree-of-freedom bistable energy harvester.

    Science.gov (United States)

    Kim, Pilkee; Nguyen, Minh Sang; Kwon, Ojin; Kim, Young-Jin; Yoon, Yong-Jin

    2016-09-28

    A system of magnetically coupled oscillators has been recently considered as a promising compact structure to integrate multiple bistable energy harvesters (BEHs), but its design is not straightforward owing to its varying potential energy pattern, which has not been understood completely yet. This study introduces the concept of phase-dependent dynamic potential in a magnetically coupled BEH system with two degrees of freedom (DOFs) to explain the underlying principle of the complicated dynamics of the system. Through theoretical simulations and analyses, two distinct dynamic regimes, called the out-of-phase and in-phase mode regimes in this report, are found to exist in the frequency regions of the 1 st and 2 nd primary intrawell resonances. For the out-of-phase mode regime, the frequency displacement (and output power) responses of the 2-DOF BEH system exhibit typical double-well dynamics, whereas for the in-phase mode regime, only single-well dynamics is observed though the system is statically bistable. These dynamic regimes are also revealed to be caused by the difference in the dynamic potential energy trajectories propagating on a high-dimensional potential energy surface. The present approach to the dynamics of the 2-DOF BEH system can be extended and applied to higher-DOF systems, which sheds light on compact and efficient designs of magnetically coupled BEH chain structures.

  9. Semiclassical spectral quantization: Application to two and four coupled molecular degrees of freedom

    International Nuclear Information System (INIS)

    De Leon, N.; Heller, E.J.

    1984-01-01

    Semiclassical quantization of the quasiperiodic vibrational motion of molecules is usually based on Einstein--Brillouin--Keller (EBK) conditions for the quantization of the classical actions. Explicit use of the EBK conditions for molecular systems of K degrees of freedom requires K quantization conditions. Therefore, explicit use of the EBK conditions becomes increasingly difficult if not impossible for polyatomic systems of three or more degrees of freedom. In this paper we propose a semiclassical quantization method which makes explicit use of phase coherence of the de Broglie wave associated with the trajectory rather than the EBK conditions. We show that taking advantage of phase coherence reduces the K quantization conditions to a single quantum condition: regardless of the number of degrees of freedom. For reasons that will become obvious we call this method ''spectral quantization.'' Polyatomic vibrational wave functions and energy eigenvalues are generated from quasiperiodic classical trajectories. The spectral method is applied to an ABA linear triatomic molecule with two degrees of freedom and to an anharmonic model of the molecule cyanoacetylene. The usefulness of the technique is demonstrated in this latter calculation since the cyanoacetylene model will have four coupled vibrational degrees of freedom

  10. Coupling between slow and fast degrees of freedom in systems with complex spectra: Driven systems

    International Nuclear Information System (INIS)

    Bulgac, A.; Dang, G.D.; Kusnezov, D.

    1995-01-01

    We consider many-body systems which display slow modes and have complex spectra of intrinsic states, as atomic nuclei, atomic clusters, deformable cavities, and so forth. The effects of the coupling between the intrinsic and the slow degrees of freedom is analyzed, by assuming random matrix properties for the intrinsic degrees of freedom and the fact that the time evolution of the slow degree of freedom modifies the intrinsic configuration of the system. By neglecting the reaction of the intrinsic degrees of freedom on the slow modes, we derive evolution equations for intrinsic state population probabilities, the average excitation energy, and their fluctuations. These evolution equations are characterized by strong memory effects, and only in the long time limit does the dynamics become Markovian. Copyright copyright 1995 Academic Press, Inc

  11. [Enhanced prenatal HIV couple oriented counselling session and couple communication about HIV (ANRS 12127 Prenahtest Trial)].

    Science.gov (United States)

    Plazy, M; Orne-Gliemann, J; Balestre, E; Miric, M; Darak, S; Butsashvili, M; Tchendjou, P; Dabis, F; Desgrées du Loû, A

    2013-08-01

    The Prenahtest study investigated the efficacy of a couple-oriented HIV counselling session (COC) in encouraging couple HIV counselling and testing, and improving intra-couple communication about sexual and reproductive health. We report here on the effect of COC on intra-couple communication about HIV. Within this 4-country trial (India, Georgia, Dominican Republic and Cameroon), 484 to 491 pregnant women per site were recruited and individually randomized to receive either the COC intervention, enhanced counselling with role playing, or standard post-test HIV counselling. Women were interviewed at recruitment, before HIV testing (T0), and 2 to 8 weeks after post-test HIV counselling (T1). Four dichotomous variables documented intra-couple communication about HIV at T1: 1) discussion about HIV, 2) discussion about condom use, 3) suggesting HIV testing and 4) suggesting couple HIV counselling to the partner. An intra-couple HIV communication index was created: low degree of communication ("yes" response to zero or one of the four variables), intermediate degree of communication ("yes" to two or three variables) or high degree of communication ("yes" to the four variables). To estimate the impact of COC on the intra-couple HIV communication index, multivariable logistic regressions were conducted. One thousand six hundred and seven women were included in the analysis of whom 54 (3.4%) were HIV-infected (49 in Cameroon). In the four countries, the counselling group was associated with intra-couple HIV communication (P≤0.03): women allocated to the COC group were significantly more likely to report high or intermediate degrees of intra-couple communication about HIV (versus low degree of communication) than women allocated to standard counselling. COC improved short-term communication about HIV within couples in different sociocultural contexts, a positive finding for a couple approach to HIV prevention. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  12. High-Degree Neurons Feed Cortical Computations.

    Directory of Open Access Journals (Sweden)

    Nicholas M Timme

    2016-05-01

    Full Text Available Recent work has shown that functional connectivity among cortical neurons is highly varied, with a small percentage of neurons having many more connections than others. Also, recent theoretical developments now make it possible to quantify how neurons modify information from the connections they receive. Therefore, it is now possible to investigate how information modification, or computation, depends on the number of connections a neuron receives (in-degree or sends out (out-degree. To do this, we recorded the simultaneous spiking activity of hundreds of neurons in cortico-hippocampal slice cultures using a high-density 512-electrode array. This preparation and recording method combination produced large numbers of neurons recorded at temporal and spatial resolutions that are not currently available in any in vivo recording system. We utilized transfer entropy (a well-established method for detecting linear and nonlinear interactions in time series and the partial information decomposition (a powerful, recently developed tool for dissecting multivariate information processing into distinct parts to quantify computation between neurons where information flows converged. We found that computations did not occur equally in all neurons throughout the networks. Surprisingly, neurons that computed large amounts of information tended to receive connections from high out-degree neurons. However, the in-degree of a neuron was not related to the amount of information it computed. To gain insight into these findings, we developed a simple feedforward network model. We found that a degree-modified Hebbian wiring rule best reproduced the pattern of computation and degree correlation results seen in the real data. Interestingly, this rule also maximized signal propagation in the presence of network-wide correlations, suggesting a mechanism by which cortex could deal with common random background input. These are the first results to show that the extent to

  13. Random-lattice models and simulation algorithms for the phase equilibria in two-dimensional condensed systems of particles with coupled internal and translational degrees of freedom

    DEFF Research Database (Denmark)

    Nielsen, Morten; Miao, Ling; Ipsen, John Hjorth

    1996-01-01

    In this work we concentrate on phase equilibria in two-dimensional condensed systems of particles where both translational and internal degrees of freedom are present and coupled through microscopic interactions, with a focus on the manner of the macroscopic coupling between the two types...... where the spin degrees of freedom are slaved by the translational degrees of freedom and develop a first-order singularity in the order-disorder transition that accompanies the lattice-melting transition. The internal degeneracy of the spin states in model III implies that the spin order...

  14. Strongly coupled partitioned six degree-of-freedom rigid body motion solver with Aitken's dynamic under-relaxation

    Directory of Open Access Journals (Sweden)

    Jeng Hei Chow

    2016-07-01

    Full Text Available An implicit method of solving the six degree-of-freedom rigid body motion equations based on the second order Adams-Bashforth-Moulten method was utilised as an improvement over the leapfrog scheme by making modifications to the rigid body motion solver libraries directly. The implementation will depend on predictor-corrector steps still residing within the hybrid Pressure Implicit with Splitting of Operators - Semi-Implicit Method for Pressure Linked Equations (PIMPLE outer corrector loops to ensure strong coupling between fluid and motion. Aitken's under-relaxation is also introduced in this study to optimise the convergence rate and stability of the coupled solver. The resulting coupled solver ran on a free floating object tutorial test case when converged matches the original solver. It further allows a varying 70%–80% reduction in simulation times compared using a fixed under-relaxation to achieve the required stability.

  15. Study on the Coupling Coordination Degree between Metropolitan Economic System and Water Environmental System - Taking Beijing as an Example

    Directory of Open Access Journals (Sweden)

    Chen Ming

    2017-01-01

    Full Text Available The generation of metropolis is the inevitable outcome of the development of urbanization to a certain stage. The economy and society of metropolis are in the rapid development, but this process brings great pressure to the ecological environment, especially the water resources environment at the same time. In this paper, the relationship between metropolitan economic system and water environmental system is deeply studied, and the concept of “coupling” is introduced. Based on the framework of “pressure-state-response” (PSR, 12 detailed indexes, such as total population and water consumption per ten thousand Yuan GDP, were selected to construct four subsystems. The coordination degree measurement model has been used to calculate the degree of coupling between the economic system and water environmental system. On this basis, the following conclusions are drawn through the example of Beijing city: (1 In the process of metropolitan development, the economic system and the water environmental system are interrelated and there exist a complex coupling mechanism. (2 With the adjustment of economic structure and the progress of technology, the coupling index between the metropolitan economic system and the water environmental system has been increasing, and this process shows an upward trend

  16. Development of a compact, fiber-coupled, six degree-of-freedom measurement system for precision linear stage metrology

    International Nuclear Information System (INIS)

    Yu, Xiangzhi; Gillmer, Steven R.; Woody, Shane C.; Ellis, Jonathan D.

    2016-01-01

    A compact, fiber-coupled, six degree-of-freedom measurement system which enables fast, accurate calibration, and error mapping of precision linear stages is presented. The novel design has the advantages of simplicity, compactness, and relatively low cost. This proposed sensor can simultaneously measure displacement, two straightness errors, and changes in pitch, yaw, and roll using a single optical beam traveling between the measurement system and a small target. The optical configuration of the system and the working principle for all degrees-of-freedom are presented along with the influence and compensation of crosstalk motions in roll and straightness measurements. Several comparison experiments are conducted to investigate the feasibility and performance of the proposed system in each degree-of-freedom independently. Comparison experiments to a commercial interferometer demonstrate error standard deviations of 0.33 μm in straightness, 0.14 μrad in pitch, 0.44 μradin yaw, and 45.8 μrad in roll.

  17. Development of a compact, fiber-coupled, six degree-of-freedom measurement system for precision linear stage metrology

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiangzhi, E-mail: xiangzhi.yu@rochester.edu; Gillmer, Steven R. [Department of Mechanical Engineering, University of Rochester, Rochester, New York 14627 (United States); Woody, Shane C. [InSituTec Incorporated, 7140 Weddington Road, Concord, North Carolina 28027 (United States); Ellis, Jonathan D. [Department of Mechanical Engineering, University of Rochester, Rochester, New York 14627 (United States); The Institute of Optics, University of Rochester, Rochester, New York 14627 (United States)

    2016-06-15

    A compact, fiber-coupled, six degree-of-freedom measurement system which enables fast, accurate calibration, and error mapping of precision linear stages is presented. The novel design has the advantages of simplicity, compactness, and relatively low cost. This proposed sensor can simultaneously measure displacement, two straightness errors, and changes in pitch, yaw, and roll using a single optical beam traveling between the measurement system and a small target. The optical configuration of the system and the working principle for all degrees-of-freedom are presented along with the influence and compensation of crosstalk motions in roll and straightness measurements. Several comparison experiments are conducted to investigate the feasibility and performance of the proposed system in each degree-of-freedom independently. Comparison experiments to a commercial interferometer demonstrate error standard deviations of 0.33 μm in straightness, 0.14 μrad in pitch, 0.44 μradin yaw, and 45.8 μrad in roll.

  18. Transformation between surface spherical harmonic expansion of arbitrary high degree and order and double Fourier series on sphere

    Science.gov (United States)

    Fukushima, Toshio

    2018-02-01

    In order to accelerate the spherical harmonic synthesis and/or analysis of arbitrary function on the unit sphere, we developed a pair of procedures to transform between a truncated spherical harmonic expansion and the corresponding two-dimensional Fourier series. First, we obtained an analytic expression of the sine/cosine series coefficient of the 4 π fully normalized associated Legendre function in terms of the rectangle values of the Wigner d function. Then, we elaborated the existing method to transform the coefficients of the surface spherical harmonic expansion to those of the double Fourier series so as to be capable with arbitrary high degree and order. Next, we created a new method to transform inversely a given double Fourier series to the corresponding surface spherical harmonic expansion. The key of the new method is a couple of new recurrence formulas to compute the inverse transformation coefficients: a decreasing-order, fixed-degree, and fixed-wavenumber three-term formula for general terms, and an increasing-degree-and-order and fixed-wavenumber two-term formula for diagonal terms. Meanwhile, the two seed values are analytically prepared. Both of the forward and inverse transformation procedures are confirmed to be sufficiently accurate and applicable to an extremely high degree/order/wavenumber as 2^{30} {≈ } 10^9. The developed procedures will be useful not only in the synthesis and analysis of the spherical harmonic expansion of arbitrary high degree and order, but also in the evaluation of the derivatives and integrals of the spherical harmonic expansion.

  19. Thermal coupling of a high temperature PEM fuel cell with a complex hydride tank

    DEFF Research Database (Denmark)

    Pfeifer, P.; Wall, C.; Jensen, Jens Oluf

    2009-01-01

    the possibilities of a thermal coupling of a high temperature PEM fuel cell operating at 160-200 degrees C. The starting temperatures and temperature hold-times before starting fuel cell operation, the heat transfer characteristics of the hydride storage tanks, system temperature, fuel cell electrical power......Sodium alanate doped with cerium catalyst has been proven to have fast kinetics for hydrogen ab- and de-sorption as well as a high gravimetric storage density around 5 wt%. The kinetics of hydrogen sorption can be improved by preparing the alanate as nanocrystalline material. However, the second...... decomposition step, i.e. the decomposition of the hexahydride to sodium hydride and aluminium which refers to 1.8 wt% hydrogen is supposed to happen above 110 degrees C. The discharge of the material is thus limited by the level of heat supplied to the hydride storage tank. Therefore, we evaluated...

  20. Fast magnetic resonance imaging based on high degree total variation

    Science.gov (United States)

    Wang, Sujie; Lu, Liangliang; Zheng, Junbao; Jiang, Mingfeng

    2018-04-01

    In order to eliminating the artifacts and "staircase effect" of total variation in Compressive Sensing MRI, high degree total variation model is proposed for dynamic MRI reconstruction. the high degree total variation regularization term is used as a constraint to reconstruct the magnetic resonance image, and the iterative weighted MM algorithm is proposed to solve the convex optimization problem of the reconstructed MR image model, In addtion, one set of cardiac magnetic resonance data is used to verify the proposed algorithm for MRI. The results show that the high degree total variation method has a better reconstruction effect than the total variation and the total generalized variation, which can obtain higher reconstruction SNR and better structural similarity.

  1. Principle Research on a Single Mass Piezoelectric Six-Degrees-of-Freedom Accelerometer

    Directory of Open Access Journals (Sweden)

    Jingcheng Liu

    2013-08-01

    Full Text Available A signal mass piezoelectric six-degrees-of-freedom (six-DOF accelerometer is put forward in response to the need for health monitoring of the dynamic vibration characteristics of high grade digitally controlled machine tools. The operating principle of the piezoelectric six-degrees-of-freedom accelerometer is analyzed, and its structure model is constructed. The numerical simulation model (finite element model of the six axis accelerometer is established. Piezoelectric quartz is chosen for the acceleration sensing element and conversion element, and its static sensitivity, static coupling interference and dynamic natural frequency, dynamic cross coupling are analyzed by ANSYS software. Research results show that the piezoelectric six-DOF accelerometer has advantages of simple and rational structure, correct sensing principle and mathematic model, good linearity, high rigidity, and theoretical natural frequency is more than 25 kHz, no nonlinear cross coupling and no complex decoupling work.

  2. Antiferromagnetic coupling in a six-coordinate high spin cobalt(II)-semiquinonato complex.

    Science.gov (United States)

    Caneschi, Andrea; Dei, Andrea; Gatteschi, Dante; Tangoulis, Vassilis

    2002-07-01

    The 3,5-di-tert-butyl-catecholato and 9,10-phenanthrenecatecholato adducts of the cobalt-tetraazamacrocycle complex Co(Me(4)cyclam)(2+) (Me(4)cyclam = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) were synthesized and oxidized. The oxidation reaction products were isolated in the solid state as hexafluorophosphate derivatives. Both these complexes can be formulated as 1:1 cobalt(II)-semiquinonato complexes, that is, Co(Me(4)cyclam)(DBSQ)PF(6) (1) and Co(Me(4)cyclam)(PhSQ)PF(6) (2), in the temperature range 4-300 K, in striking contrast with the charge distribution found in similar adducts formed by related tetraazamacrocycles. The synthesis strategy and the structural, spectroscopic, and magnetic properties are reported and discussed. The crystallographic data for 2 are as follows: monoclinic, space group P2(1)/a, nomicron. 14, a = 14.087(4) A, b = 15.873(4) A, c = 14.263 (7) A, alpha = 89.91(3) degrees, beta = 107.34(2) degrees, gamma = 90.08(2) degrees, Z = 4. Both these complexes are characterized by triplet electronic ground states arising from the antiferromagnetic coupling between the high-spin d(7) metal ion and the radical ligand.

  3. Fe-Catalyzed Synthesis of Porous Carbons Spheres with High Graphitization Degree for High-Performance Supercapacitors

    Science.gov (United States)

    Zhu, Jun; Shi, Hongwei; Zhuo, Xin; Hu, Yalin

    2017-10-01

    We have developed a facile and efficient Fe-catalyzed method for fabrication of porous carbons spheres with high graphitization degree (GNPCs) using glucose as carbon precursor at relatively low carbonization temperature. GNPCs not only have relatively large accessible ion surface area to accommodate greater capacity but also high graphitization degree to accelerate ion diffusion. As a typical application, we demonstrate that GNPCs exhibit excellent electrochemical performance for use in supercapacitors, with high specific capacity of 150.6 F g-1 at current density of 1 A g-1 and good rate capability and superior cycling stability over 10,000 cycles, confirming their potential application for energy storage. Moreover, it is believed that this method offers a new strategy for synthesis of porous carbons with high graphitization degree.

  4. High degree gravitational sensitivity from Mars orbiters for the GMM-1 gravity model

    Science.gov (United States)

    Lerch, F. J.; Smith, D. E.; Chan, J. C.; Patel, G. B.; Chinn, D. S.

    1994-01-01

    Orbital sensitivity of the gravity field for high degree terms (greater than 30) is analyzed on satellites employed in a Goddard Mars Model GMM-1, complete in spherical harmonics through degree and order 50. The model is obtained from S-band Doppler data on Mariner 9 (M9), Viking Orbiter 1 (VO1), and Viking Orbiter 2 (VO2) spacecraft, which were tracked by the NASA Deep Space Network on seven different highly eccentric orbits. The main sensitivity of the high degree terms is obtained from the VO1 and VO2 low orbits (300 km periapsis altitude), where significant spectral sensitivity is seen for all degrees out through degree 50. The velocity perturbations show a dominant effect at periapsis and significant effects out beyond the semi-latus rectum covering over 180 degrees of the orbital groundtrack for the low altitude orbits. Because of the wideband of periapsis motion covering nearly 180 degrees in w and +39 degrees in latitude coverage, the VO1 300 km periapsis altitude orbit with inclination of 39 degrees gave the dominant sensitivity in the GMM-1 solution for the high degree terms. Although the VO2 low periapsis orbit has a smaller band of periapsis mapping coverage, it strongly complements the VO1 orbit sensitivity for the GMM-1 solution with Doppler tracking coverage over a different inclination of 80 degrees.

  5. Rovibrational coupling in molecular nitrogen at high temperature: An atomic-level study

    Energy Technology Data Exchange (ETDEWEB)

    Valentini, Paolo, E-mail: vale0142@umn.edu; Norman, Paul, E-mail: norma198@umn.edu; Zhang, Chonglin, E-mail: zhang993@umn.edu; Schwartzentruber, Thomas E., E-mail: schwart@aem.umn.edu [Department of Aerospace Engineering and Mechanics, College of Science and Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-05-15

    This article contains an atomic-level numerical investigation of rovibrational relaxation in molecular nitrogen at high temperature (>4000 K), neglecting dissociation. We conduct our study with the use of pure Molecular Dynamics (MD) and Classical Trajectory Calculations (CTC) Direct Simulation Monte Carlo (DSMC), verified to produce statistically identical results at the conditions of interest here. MD and CTC DSMC solely rely on the specification of a potential energy surface: in this work, the site-site Ling-Rigby potential. Additionally, dissociation is prevented by modeling the N–N bond either as a harmonic or an anharmonic spring. The selected molecular model was shown to (i) recover the shear viscosity (obtained from equilibrium pure MD Green-Kubo calculations) of molecular nitrogen over a wide range of temperatures, up to dissociation; (ii) predict well the near-equilibrium rotational relaxation behavior of N{sub 2}; (iii) reproduce vibrational relaxation times in excellent accordance with the Millikan-White correlation and previous semi-classical trajectory calculations in the low temperature range, i.e., between 4000 K and 10 000 K. By simulating isothermal relaxations in a periodic box, we found that the traditional two-temperature model assumptions become invalid at high temperatures (>10 000 K), due to a significant coupling between rotational and vibrational modes for bound states. This led us to add a modification to both the Jeans and the Landau-Teller equations to include a coupling term, essentially described by an additional relaxation time for internal energy equilibration. The degree of anharmonicity of the N{sub 2} bond determines the strength of the rovibrational coupling. Although neglecting N{sub 2} dissociation only provides a partial description of a nitrogen system at very high temperatures, high-energy trends for bound-bound transitions are essential to understand nonequilibrium gas flows, with possible implications on rovibration

  6. Rovibrational coupling in molecular nitrogen at high temperature: An atomic-level study

    International Nuclear Information System (INIS)

    Valentini, Paolo; Norman, Paul; Zhang, Chonglin; Schwartzentruber, Thomas E.

    2014-01-01

    This article contains an atomic-level numerical investigation of rovibrational relaxation in molecular nitrogen at high temperature (>4000 K), neglecting dissociation. We conduct our study with the use of pure Molecular Dynamics (MD) and Classical Trajectory Calculations (CTC) Direct Simulation Monte Carlo (DSMC), verified to produce statistically identical results at the conditions of interest here. MD and CTC DSMC solely rely on the specification of a potential energy surface: in this work, the site-site Ling-Rigby potential. Additionally, dissociation is prevented by modeling the N–N bond either as a harmonic or an anharmonic spring. The selected molecular model was shown to (i) recover the shear viscosity (obtained from equilibrium pure MD Green-Kubo calculations) of molecular nitrogen over a wide range of temperatures, up to dissociation; (ii) predict well the near-equilibrium rotational relaxation behavior of N 2 ; (iii) reproduce vibrational relaxation times in excellent accordance with the Millikan-White correlation and previous semi-classical trajectory calculations in the low temperature range, i.e., between 4000 K and 10 000 K. By simulating isothermal relaxations in a periodic box, we found that the traditional two-temperature model assumptions become invalid at high temperatures (>10 000 K), due to a significant coupling between rotational and vibrational modes for bound states. This led us to add a modification to both the Jeans and the Landau-Teller equations to include a coupling term, essentially described by an additional relaxation time for internal energy equilibration. The degree of anharmonicity of the N 2 bond determines the strength of the rovibrational coupling. Although neglecting N 2 dissociation only provides a partial description of a nitrogen system at very high temperatures, high-energy trends for bound-bound transitions are essential to understand nonequilibrium gas flows, with possible implications on rovibration

  7. Asymptotic numerical method for multi-degree-of-freedom nonlinear dynamic systems

    International Nuclear Information System (INIS)

    Mei Shuli; Du Chengjin; Zhang Senwen

    2008-01-01

    Homotopy perturbation method (HPM) proposed by Ji-Huan He is very effective and convenient for single-degree-of-freedom systems. In this paper a coupling technique of He's method and precise integration method (PIM) is suggested to solve multi-degree-of-freedom nonlinear dynamic systems. The new technique keeps the merits of the two methods. Some examples are given to illustrate its effectiveness and convenience. Furthermore the obtained solution is of high accuracy

  8. Method for Measurement of Multi-Degrees-of-Freedom Motion Parameters Based on Polydimethylsiloxane Cross-Coupling Diffraction Gratings

    Science.gov (United States)

    Duan, Junping; Zhu, Qiang; Qian, Kun; Guo, Hao; Zhang, Binzhen

    2017-08-01

    This work presents a multi-degrees-of-freedom motion parameter measurement method based on the use of cross-coupling diffraction gratings that were prepared on the two sides of a polydimethylsiloxane (PDMS) substrate using oxygen plasma processing technology. The laser beam that travels pass the cross-coupling optical grating would be diffracted into a two-dimensional spot array. The displacement and the gap size of the spot-array were functions of the movement of the laser source, as explained by the Fraunhofer diffraction effect. A 480 × 640 pixel charge-coupled device (CCD) was used to acquire images of the two-dimensional spot-array in real time. A proposed algorithm was then used to obtain the motion parameters. Using this method and the CCD described above, the resolutions of the displacement and the deflection angle were 0.18 μm and 0.0075 rad, respectively. Additionally, a CCD with a higher pixel count could improve the resolutions of the displacement and the deflection angle to sub-nanometer and micro-radian scales, respectively. Finally, the dynamic positions of hovering rotorcraft have been tracked and checked using the proposed method, which can be used to correct the craft's position and provide a method for aircraft stabilization in the sky.

  9. High degree-of-freedom dynamic manipulation

    Science.gov (United States)

    Murphy, Michael P.; Stephens, Benjamin; Abe, Yeuhi; Rizzi, Alfred A.

    2012-06-01

    The creation of high degree of freedom dynamic mobile manipulation techniques and behaviors will allow robots to accomplish difficult tasks in the field. We are investigating the use of the body and legs of legged robots to improve the strength, velocity, and workspace of an integrated manipulator to accomplish dynamic manipulation. This is an especially challenging task, as all of the degrees of freedom are active at all times, the dynamic forces generated are high, and the legged system must maintain robust balance throughout the duration of the tasks. To accomplish this goal, we are utilizing trajectory optimization techniques to generate feasible open-loop behaviors for our 28 dof quadruped robot (BigDog) by planning the trajectories in a 13 dimensional space. Covariance Matrix Adaptation techniques are utilized to optimize for several criteria such as payload capability and task completion speed while also obeying constraints such as torque and velocity limits, kinematic limits, and center of pressure location. These open-loop behaviors are then used to generate feed-forward terms, which are subsequently used online to improve tracking and maintain low controller gains. Some initial results on one of our existing balancing quadruped robots with an additional human-arm-like manipulator are demonstrated on robot hardware, including dynamic lifting and throwing of heavy objects 16.5kg cinder blocks, using motions that resemble a human athlete more than typical robotic motions. Increased payload capacity is accomplished through coordinated body motion.

  10. Coupling Ideality of Integrated Planar High-Q Microresonators

    Science.gov (United States)

    Pfeiffer, Martin H. P.; Liu, Junqiu; Geiselmann, Michael; Kippenberg, Tobias J.

    2017-02-01

    Chip-scale optical microresonators with integrated planar optical waveguides are useful building blocks for linear, nonlinear, and quantum-optical photonic devices alike. Loss reduction through improving fabrication processes results in several integrated microresonator platforms attaining quality (Q ) factors of several millions. Beyond the improvement of the quality factor, the ability to operate the microresonator with high coupling ideality in the overcoupled regime is of central importance. In this regime, the dominant source of loss constitutes the coupling to a single desired output channel, which is particularly important not only for quantum-optical applications such as the generation of squeezed light and correlated photon pairs but also for linear and nonlinear photonics. However, to date, the coupling ideality in integrated photonic microresonators is not well understood, in particular, design-dependent losses and their impact on the regime of high ideality. Here we investigate design-dependent parasitic losses described by the coupling ideality of the commonly employed microresonator design consisting of a microring-resonator waveguide side coupled to a straight bus waveguide, a system which is not properly described by the conventional input-output theory of open systems due to the presence of higher-order modes. By systematic characterization of multimode high-Q silicon nitride microresonator devices, we show that this design can suffer from low coupling ideality. By performing 3D simulations, we identify the coupling to higher-order bus waveguide modes as the dominant origin of parasitic losses which lead to the low coupling ideality. Using suitably designed bus waveguides, parasitic losses are mitigated with a nearly unity ideality and strong overcoupling (i.e., a ratio of external coupling to internal resonator loss rate >9 ) are demonstrated. Moreover, we find that different resonator modes can exchange power through the coupler, which, therefore

  11. Highly dispersive transparency in coupled metamaterials

    International Nuclear Information System (INIS)

    Thuy, V T T; Park, J W; Lee, Y P; Tung, N T; Lam, V D; Rhee, J Y

    2010-01-01

    We investigate the coupling between bright and quasi-dark eigenmodes in a planar metamaterial supporting highly dispersive transparency. The specific design of such a metamaterial consists of a cut wire (CW) and a single-gap split-ring resonator (SRR). Through the numerical simulation and the equivalent-circuit analysis, we demonstrate that the response of the SRR, which is weakly excited by external electric field, plays the role of a quasi-dark eigenmode in the presence of a strongly radiative CW. Furthermore, by extending and relating our study to the trapped mode resonances and the coupling between dark and bright modes, a more comprehensive perspective for the metamaterial realization of highly dispersive transmission and slow-light applications is provided

  12. Coupling of collective and single-particle degrees of freedom in atomic nuclei (commentary to thesis qualifying for assistant-professorship)

    International Nuclear Information System (INIS)

    Chlebowska, D.

    1992-11-01

    The analysis of the spectroscopic properties of the spherical and transitional nuclei is performed from the point of view of the relation between the single-particle and collective degrees of freedom on the ground of the core-particle coupling model with the total angular momentum conserved and without any unphysical parameters (such as the attenuation parameter). A new definition of the rotational alignment is given. The staggering effect is interpreted as a manifestation of the vibrational structure. The rotational dependence of the energy gap parameter is shown to have an influence on the energy spectra of the transitional nuclei. The nuclei with A 130 are shown to have a tendency to be rather rigid. The vibrational and rotational structures, and the magnitude of the rotation-particle coupling in the considered nuclei are determined. 18 figs., 9 tabs., 66 refs. (author)

  13. Transient simulation of an endothermic chemical process facility coupled to a high temperature reactor: Model development and validation

    International Nuclear Information System (INIS)

    Brown, Nicholas R.; Seker, Volkan; Revankar, Shripad T.; Downar, Thomas J.

    2012-01-01

    Highlights: ► Models for PBMR and thermochemical sulfur cycle based hydrogen plant are developed. ► Models are validated against available data in literature. ► Transient in coupled reactor and hydrogen plant system is studied. ► For loss-of-heat sink accident, temperature feedback within the reactor core enables shut down of the reactor. - Abstract: A high temperature reactor (HTR) is a candidate to drive high temperature water-splitting using process heat. While both high temperature nuclear reactors and hydrogen generation plants have high individual degrees of development, study of the coupled plant is lacking. Particularly absent are considerations of the transient behavior of the coupled plant, as well as studies of the safety of the overall plant. The aim of this document is to contribute knowledge to the effort of nuclear hydrogen generation. In particular, this study regards identification of safety issues in the coupled plant and the transient modeling of some leading candidates for implementation in the Nuclear Hydrogen Initiative (NHI). The Sulfur Iodine (SI) and Hybrid Sulfur (HyS) cycles are considered as candidate hydrogen generation schemes. Three thermodynamically derived chemical reaction chamber models are coupled to a well-known reference design of a high temperature nuclear reactor. These chemical reaction chamber models have several dimensions of validation, including detailed steady state flowsheets, integrated loop test data, and bench scale chemical kinetics. The models and coupling scheme are presented here, as well as a transient test case initiated within the chemical plant. The 50% feed flow failure within the chemical plant results in a slow loss-of-heat sink (LOHS) accident in the nuclear reactor. Due to the temperature feedback within the reactor core the nuclear reactor partially shuts down over 1500 s. Two distinct regions are identified within the coupled plant response: (1) immediate LOHS due to the loss of the sulfuric

  14. Multiple-state Feshbach resonances mediated by high-order couplings

    International Nuclear Information System (INIS)

    Hemming, Christopher J.; Krems, Roman V.

    2008-01-01

    We present a study of multistate Feshbach resonances mediated by high-order couplings. Our analysis focuses on a system with one open scattering state and multiple bound states. The scattering state is coupled to one off-resonant bound state and multiple Feshbach resonances are induced by a sequence of indirect couplings between the closed channels. We derive a general recursive expression that can be used to fit the experimental data on multistate Feshbach resonances involving one continuum state and several bound states and present numerical solutions for several model systems. Our results elucidate general features of multistate Feshbach resonances induced by high-order couplings and suggest mechanisms for controlling collisions of ultracold atoms and molecules with external fields

  15. Geometry of infinite planar maps with high degrees

    DEFF Research Database (Denmark)

    Budd, Timothy George; Curien, Nicolas

    2017-01-01

    We study the geometry of infinite random Boltzmann planar maps with vertices of high degree. These correspond to the duals of the Boltzmann maps associated to a critical weight sequence (qk)k≥0 for the faces with polynomial decay k-ɑ with ɑ ∈ (3/2,5/2)which have been studied by Le Gall & Miermont...

  16. Direct transitions from high-K isomers to low-K bands -- {gamma} softness or coriolis coupling

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yoshifumi R.; Narimatsu, Kanako; Ohtsubo, Shin-Ichi [Kyushu Univ., Fukuoka (Japan)] [and others

    1996-12-31

    Recent measurements of direct transitions from high-K isomers to low-K bands reveal severe break-down of the K-selection rule and pose the problem of how to understand the mechanism of such K-violation. The authors recent systematic calculations by using a simple {gamma}-tunneling model reproduced many of the observed hindrances, indicating the importance of the {gamma} softness. However, there are some data which cannot be explained in terms of the {gamma}-degree of freedom. In this talk, the authors also discuss the results of conventional Coriolis coupling calculations, which is considered to be another important mechanism.

  17. 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.

  18. Implementation of a Forth-Order Aeroelastic Coupling into a Viscous-Inviscid Flow Solver with Experimental Validation (for One Degree of Freedom)

    Science.gov (United States)

    Bartholomay, Sirko; Ramos-García, Néstor; Mikkelsen, Robert Flemming; Technical University of Denmark (DTU)-WInd Energy Team

    2014-11-01

    The viscous-inviscid flow solver Q3UIC for 2D aerodynamics has recently been developed at the Technical University of Denmark. The Q3UIC solver takes viscous and unsteady effects into account by coupling an unsteady inviscid panel method with the integral boundary layer equations by means of a strong coupling between the viscous and inviscid parts, and in this respect differs from other classic panel codes e.g. Xfoil. In the current work a Runge-Kutta-Nyström scheme was employed to couple inertial, elastic and aerodynamical forces and moments calculated by Q3UIC for a two-dimensional blade section in the time-domain. Numerical simulations are validated by a three step experimental verification process carried out in the low-turbulence wind tunnel at DTU. First, a comparison against steady experiments for a NACA 64418 profile and a flexible trailing edge flap is presented for different fixed flap angles, and second, the measured aerodynamic characteristics considering prescribed motion of the airfoil with a moving flap are compared to the Q3UIC predictions. Finally, an aeroelastic experiment for one degree of freedom-airfoil pitching- is used to evaluate the accuracy of aeroelastic coupling.

  19. The Southern Oscillation in a coupled GCM: Implications for climate sensitivity and climate change

    International Nuclear Information System (INIS)

    Meehl, G.A.

    1990-01-01

    Results are presented from a global coupled ocean-atmosphere general circulation climate model developed at the National Center for Atmospheric Research. The atmospheric part of the coupled model is a global spectral (R15, 4.5 degree latitude by 7.5 degree longitude, 9 layers in the vertical) general circulation model. The ocean is coarse-grid (5 degree latitude by 5 degree longitude, 4 layers in the vertical) global general circulation model. The coupled model includes a simple thermodynamic sea-ice model. Due mainly to inherent limitations in the ocean model, the coupled model simulates sea surface temperatures that are too low in the tropics and too high in the extratropics in the mean. In spite of these limitations, the coupled model simulates active interannual variability of the global climate system involving signals in the tropical Pacific that resemble, in some respects, the observed Southern Oscillation. These signals in the tropics are associated with teleconnections to the extratropics of both hemispheres. The implications of this model-simulated interannual variability of the coupled system relating to climate sensitivity and climate change due to an increase of atmospheric carbon dioxide are discussed

  20. The Southern Oscillation in a coupled GCM: Implications for climate sensitivity and climate change

    International Nuclear Information System (INIS)

    Meehl, G.A.

    1991-01-01

    Results are presented from a global coupled ocean-atmosphere general circulation climate model developed at the National Center for Atmospheric Research. The atmospheric part of the coupled model is a global spectral (R15, 4.5 degree latitude by 7.5 degree longitude, 9 layers in the vertical) general circulation model. The ocean is coarse-grid (5 degree latitude by 5 degree longitude, 4 layers in the vertical) global general circulation model. The coupled model includes a simple thermodynamic sea-ice model. Due mainly to inherent limitations in the ocean model, the coupled model simulates sea surface temperatures that are too low in the tropics and too high in the extratropics in the mean. In spite of these limitations, the coupled model simulates active interannual variability of the global climate system involving signals in the tropical Pacific that resemble, in some respects, the observed Southern Oscillation. These signals in the tropics are associated with teleconnections to the extratropics of both hemispheres. The implications of this model-simulated interannual variability of the coupled system relating to climate sensitivity and climate change due to an increase of atmospheric carbon dioxide are discussed. 25 refs.; 9 figs

  1. 28 CFR 570.43 - Inmates requiring a high degree of control and supervision.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Inmates requiring a high degree of control and supervision. 570.43 Section 570.43 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE COMMUNITY PROGRAMS AND RELEASE COMMUNITY PROGRAMS Escorted Trips § 570.43 Inmates requiring a high degree of control and supervision. Only the...

  2. Running coupling corrections to high energy inclusive gluon production

    International Nuclear Information System (INIS)

    Horowitz, W.A.; Kovchegov, Yuri V.

    2011-01-01

    We calculate running coupling corrections for the lowest-order gluon production cross section in high energy hadronic and nuclear scattering using the BLM scale-setting prescription. In the final answer for the cross section the three powers of fixed coupling are replaced by seven factors of running coupling, five in the numerator and two in the denominator, forming a 'septumvirate' of running couplings, analogous to the 'triumvirate' of running couplings found earlier for the small-x BFKL/BK/JIMWLK evolution equations. It is interesting to note that the two running couplings in the denominator of the 'septumvirate' run with complex-valued momentum scales, which are complex conjugates of each other, such that the production cross section is indeed real. We use our lowest-order result to conjecture how running coupling corrections may enter the full fixed-coupling k T -factorization formula for gluon production which includes nonlinear small-x evolution.

  3. Stagger angle dependence of inertial and elastic coupling in bladed disks

    Science.gov (United States)

    Crawley, E. F.; Mokadam, D. R.

    1984-01-01

    Conditions which necessitate the inclusion of disk and shaft flexibility in the analysis of blade response in rotating blade-disk-shaft systems are derived in terms of nondimensional parameters. A simple semianalytical Rayleigh-Ritz model is derived in which the disk possesses all six rigid body degrees of freedom, which are elastically constrained by the shaft. Inertial coupling by the rigid body motion of the disk on a flexible shaft and out-of-plane elastic coupling due to disk flexure are included. Frequency ratios and mass ratios, which depend on the stagger angle, are determined for three typical rotors: a first stage high-pressure core compressor, a high bypass ratio fan, and an advanced turboprop. The stagger angle controls the degree of coupling in the blade-disk system. In the blade-disk-shaft system, the stagger angle determines whether blade-disk motion couples principally to the out-of-plane or in-plane motion of the disk on the shaft. The Ritz analysis shows excellent agreement with experimental results.

  4. Electromagnetic coupling of high-altitude, nuclear electromagnetic pulses

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    We have used scale models to measure the predicted coupling of electromagnetic fields simulating the effects of high-altitude nuclear electromagnetic pulses (HEMP) on the interior surfaces of electronic components. Predictive tools for exterior coupling are adequate. For interior coupling, however, such tools are in their infancy. Our methodological approach combines analytical, computational, and laboratory techniques in a complementary way to take advantage of their separate strengths. Computer models are a promising tool, as they can be used to treat complex objects with arbitrary shapes, dielectrics, and cables, and multiple apertures. Laboratory tests can expand the domain of investigation even further

  5. Study of gain-coupled distributed feedback laser based on high order surface gain-coupled gratings

    Science.gov (United States)

    Gao, Feng; Qin, Li; Chen, Yongyi; Jia, Peng; Chen, Chao; Cheng, LiWen; Chen, Hong; Liang, Lei; Zeng, Yugang; Zhang, Xing; Wu, Hao; Ning, Yongqiang; Wang, Lijun

    2018-03-01

    Single-longitudinal-mode, gain-coupled distributed feedback (DFB) lasers based on high order surface gain-coupled gratings are achieved. Periodic surface metal p-contacts with insulated grooves realize gain-coupled mechanism. To enhance gain contrast in the quantum wells without the introduction of effective index-coupled effect, groove length and depth were well designed. Our devices provided a single longitudinal mode with the maximum CW output power up to 48.8 mW/facet at 971.31 nm at 250 mA without facet coating, 3dB linewidth (39 dB). Optical bistable characteristic was observed with a threshold current difference. Experimentally, devices with different cavity lengths were contrasted on power-current and spectrum characteristics. Due to easy fabrication technique and stable performance, it provides a method of fabricating practical gain-coupled distributed feedback lasers for commercial applications.

  6. High-brightness fiber-coupled pump laser development

    Science.gov (United States)

    Price, Kirk; Karlsen, Scott; Leisher, Paul; Martinsen, Robert

    2010-02-01

    We report on the continued development of high brightness laser diode modules at nLIGHT Photonics. These modules, based on nLIGHT's PearlTM product platform, demonstrate excellence in output power, brightness, wavelength stabilization, and long wavelength performance. This system, based on 14 single emitters, is designed to couple diode laser light into a 105 μm fiber at an excitation NA of under 0.14. We demonstrate over 100W of optical power at 9xx nm with a diode brightness exceeding 20 MW/cm2-str with an operating efficiency of approximately 50%. Additional results show over 70W of optical coupled at 8xx nm. Record brilliance at wavelengths 14xx nm and longer will also be demonstrated, with over 15 W of optical power with a beam quality of 7.5 mm-mrad. These results of high brightness, high efficiency, and wavelength stabilization demonstrate the pump technology required for next generation solid state and fiber lasers.

  7. High Degree Cubature Federated Filter for Multisensor Information Fusion with Correlated Noises

    Directory of Open Access Journals (Sweden)

    Lijun Wang

    2016-01-01

    Full Text Available This paper proposes an improved high degree cubature federated filter for the nonlinear fusion system with cross-correlation between process and measurement noises at the same time using the fifth-degree cubature rule and the decorrelated principle in its local filters. The master filter of the federated filter adopts the no-reset mode to fuse local estimates of local filters to generate a global estimate according to the scalar weighted rule. The air-traffic maneuvering target tracking simulations are performed between the proposed filter and the fifth-degree cubature federated filter. Simulations results demonstrate that the proposed filter not only can achieve almost the same accuracy as the fifth-degree cubature federated filter with independent white noises, but also has superior performance to the fifth-degree cubature federated filter while the noises are cross-correlated at the same time.

  8. High efficiency nebulization for helium inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Jorabchi, Kaveh; McCormick, Ryan; Levine, Jonathan A.; Liu Huiying; Nam, S.-H.; Montaser, Akbar

    2006-01-01

    A pneumatically-driven, high efficiency nebulizer is explored for helium inductively coupled plasma mass spectrometry. The aerosol characteristics and analyte transport efficiencies of the high efficiency nebulizer for nebulization with helium are measured and compared to the results obtained with argon. Analytical performance indices of the helium inductively coupled plasma mass spectrometry are evaluated in terms of detection limits and precision. The helium inductively coupled plasma mass spectrometry detection limits obtained with the high efficiency nebulizer at 200 μL/min are higher than those achieved with the ultrasonic nebulizer consuming 2 mL/min solution, however, precision is generally better with high efficiency nebulizer (1-4% vs. 3-8% with ultrasonic nebulizer). Detection limits with the high efficiency nebulizer at 200 μL/min solution uptake rate approach those using ultrasonic nebulizer upon efficient desolvation with a heated spray chamber followed by a Peltier-cooled multipass condenser

  9. Do current data prefer a nonminimally coupled inflaton?

    International Nuclear Information System (INIS)

    Ramírez Rodríguez, H.

    2016-01-01

    Inflation provides the most theoretically attractive and observationally successful cosmological scenario able to generate the initial conditions of our universe. From the theoretical viewpoint, this picture is usually understood as the dynamics of a single new scalar degree of freedom, the inflaton, minimally coupled to gravity. However, generally the inflaton is expected to have a nonminimal coupling to the Ricci scalar. While the minimally-coupled version of the chaotic model of inflation is ruled out at more than 99% confidence level (for 50 e-folds of inflation), in this talk we will see that the presence of such coupling, for the chaotic model, is highly favoured with respect to the latest analysis of Planck and BICEP2. (author)

  10. Impedance Based Characterization of a High-Coupled Screen Printed PZT Thick Film Unimorph Energy Harvester

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, R.; Borregaard, L. M.

    2014-01-01

    The single degree of freedom mass-spring-damper system is the most common approach for deriving a full electromechanical model for the piezoelectric vibration energy harvester. In this paper, we revisit this standard electromechanical model by focusing on the impedance of the piezoelectric device...... parameters which, by means of the piezoelectric impedance expression, all can be determined accurately by electrical measurements. It is shown how four of five lumped parameters can be determined from a single impedance measurement scan, considerably reducing the characterization effort. The remaining...... parameter is determined from shaker measurements, and a highly accurate agreement is found between model and measurements on a unimorph MEMS-based screen printed PZT harvester. With a high coupling term K-2 Q similar or equal to 7, the harvester exhibits two optimum load points. The peak power performance...

  11. Techno-economic study of hydrogen production by high temperature electrolysis coupled with an EPR-water steam production and coupling possibilities

    International Nuclear Information System (INIS)

    Tinoco, R. R.; Bouallou, C.; Mansilla, C.; Werkoff, F.

    2007-01-01

    Nuclear reactors present a wide range of coupling possibilities with several industrial processes, hydrogen production being one of them. Among the Pressurised Water nuclear Reactors (PWR), the new European Pressurised Reactor (EPR) offers the water steam production at low-medium temperatures, from 230 degree Celsius to 330 degree Celsius for the primary and secondary exchange circuits. The use of this water steam for hydrogen production by High Temperature Electrolysis is the subject of this study, under a French context. The study of this coupling, has considered two hypotheses. First, water steam drawing off in secondary circuit has been evaluated in terms of possible impact in electricity production and reactor availability. After the drawing off at 78 bar (EPR secondary circuit pressure), pressure has to be dropped in order to protect the high temperature electrolyser from damage, so an isenthalpic drop has been considered. Liquid-vapour equilibrium happens with pressure drops, so separation of gas phase and recycling of liquid phase are proposed. Second, only water steam production with an EPR has been evaluated. The feed water enters the secondary circuit and passes from liquid phase to vapour in the steam generators, and then all steam is canalized to the high temperature electrolyser. The potentiality of water steam production in the EPR has been evaluated from 15 to 40 bar. Small reactors could be the best choice if only water steam production is considered. After steam production, it steam enters into the High Temperature Electrolysis process, like a cold stream for two parallel series of three heat exchangers reaching temperatures up to 950 degree Celsius. Then the steam is heated by an electric device and finally it enters the electrolyser. The electrolysis product streams (hydrogen-steam mixture and oxygen) are used in the heat exchangers like hot streams. For both hypotheses, information about water composition has been studied in order to minimise

  12. Using a Coupled Human-Natural System to Assess the Vulnerability of the Karst Landform Region in China

    Directory of Open Access Journals (Sweden)

    Xiang He

    2015-09-01

    Full Text Available Guizhou Plateau is a region in China that typically shows the contradictory human-earth system. A vulnerability assessment indicator system was constructed to explore the coupled human-natural system characteristic of the karst landform based on the grey correlation analysis mathematic model. The quantitative assessment results show that Qiandongnan and Tongren Districts belong to the slight degree of the sensitivity evaluation index. Bijie district belongs to the middle degree and the other districts of Guizhou Plateau belong to the light degree. In terms of the exposure and resilience evaluation index, only Guiyang City belongs to the slight degree and other districts are in the middle degree. Thus, Guizhou Plateau could be divided into three level zones based on the comprehensive vulnerability degree of the coupled human-natural system. The strong degree vulnerability zone includes Liupanshui City, Bijie City, Anshun City, and Qiannan District. The middle degree vulnerability zone includes the districts of Qiandongnan, Qianxinan, and Tongren and the city of Zunyi. The slight degree vulnerability zone only includes Guiyang City. The research results suggest that the coupled human-natural system in Guizhou Plateau has a high vulnerability.

  13. Strong coupling constant extraction from high-multiplicity Z +jets observables

    Science.gov (United States)

    Johnson, Mark; Maître, Daniel

    2018-03-01

    We present a strong coupling constant extraction at next-to-leading order QCD accuracy using ATLAS Z +2 ,3,4 jets data. This is the first extraction using processes with a dependency on high powers of the coupling constant. We obtain values of the strong coupling constant at the Z mass compatible with the world average and with uncertainties commensurate with other next-to-leading order extractions at hadron colliders. Our most conservative result for the strong coupling constant is αS(MZ)=0.117 8-0.0043+0.0051 .

  14. Similar Others in Same-Sex Couples' Social Networks.

    Science.gov (United States)

    LeBlanc, Allen J; Frost, David M; Alston-Stepnitz, Eli; Bauermeister, Jose; Stephenson, Rob; Woodyatt, Cory R; de Vries, Brian

    2015-01-01

    Same-sex couples experience unique minority stressors. It is known that strong social networks facilitate access to psychosocial resources that help people reduce and manage stress. However, little is known about the social networks of same-sex couples, in particular their connections to other same-sex couples, which is important to understand given that the presence of similar others in social networks can ameliorate social stress for stigmatized populations. In this brief report, we present data from a diverse sample of 120 same-sex couples in Atlanta and San Francisco. The median number of other same-sex couples known was 12; couples where one partner was non-Hispanic White and the other a person of color knew relatively few other same-sex couples; and there was a high degree of homophily within the social networks of same-sex couples. These data establish a useful starting point for future investigations of couples' social networks, especially couples whose relationships are stigmatized or marginalized in some way. Better understandings of the size, composition, and functions of same-sex couples' social networks are critically needed.

  15. Alternative RF coupling configurations for H− ion sources

    International Nuclear Information System (INIS)

    Briefi, S.; Fantz, U.; Gutmann, P.

    2015-01-01

    RF heated sources for negative hydrogen ions both for fusion and accelerators require very high RF powers in order to achieve the required H − current what poses high demands on the RF generators and the RF circuit. Therefore it is highly desirable to improve the RF efficiency of the sources. This could be achieved by applying different RF coupling concepts than the currently used inductive coupling via a helical antenna, namely Helicon coupling or coupling via a planar ICP antenna enhanced with ferrites. In order to investigate the feasibility of these concepts, two small laboratory experiments have been set up. The PlanICE experiment, where the enhanced inductive coupling is going to be investigated, is currently under assembly. At the CHARLIE experiment systematic measurements concerning Helicon coupling in hydrogen and deuterium are carried out. The investigations show that a prominent feature of Helicon discharges occurs: the so-called low-field peak. This is a local improvement of the coupling efficiency at a magnetic field strength of a few mT which results in an increased electron density and dissociation degree. The full Helicon mode has not been achieved yet due to the limited available RF power and magnetic field strength but it might be sufficient for the application of the coupling concept to ion sources to operate the discharge in the low-field-peak region

  16. Layout Capacitive Coupling and Structure Impacts on Integrated High Voltage Power MOSFETs

    DEFF Research Database (Denmark)

    Fan, Lin; Knott, Arnold; Jørgensen, Ivan Harald Holger

    2016-01-01

    The switching performances of the integrated high voltage power MOSFETs that have prevailing interconnection matrices are being heavily influenced by the parasitic capacitive coupling of on-chip metal wires. The mechanism of the side-byside coupling is generally known, however, the layer-to-layer......The switching performances of the integrated high voltage power MOSFETs that have prevailing interconnection matrices are being heavily influenced by the parasitic capacitive coupling of on-chip metal wires. The mechanism of the side-byside coupling is generally known, however, the layer...... extraction tool shows that the side-by-side coupling dominated structure can perform better than the layer-to-layer coupling dominated structure, in terms of on-resistance times input or output capacitance, by 9.2% and 4.9%, respectively....

  17. Coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry for arsenic speciation.

    Science.gov (United States)

    Cheng, Heyong; Shen, Lihuan; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao

    2018-04-01

    Nanoliter high-performance liquid chromatography shows low consumption of solvents and samples, offering one of the best choices for arsenic speciation in precious samples in combination with inuctively coupled plasma mass spectrometry. A systematic investigation on coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry from instrument design to injected sample volume and mobile phase was performed in this study. Nanoflow mobile phase was delivered by flow splitting using a conventional high-pressure pump with reuse of mobile phase waste. Dead volume was minimized to 60 nL for the sheathless interface based on the previously developed nanonebulizer. Capillary columns for nanoliter high-performance liquid chromatography were found to be sensitive to sample loading volume. An apparent difference was also found between the mobile phases for nanoliter and conventional high-performance liquid chromatography. Baseline separation of arsenite, arsenate, monomethylarsenic, and dimethylarsenic was achieved within 11 min on a 15 cm C 18 capillary column and within 12 min on a 25 cm strong anion exchange column. Detection limits of 0.9-1.8 μg/L were obtained with precisions variable in the range of 1.6-4.2%. A good agreement between determined and certified values of a certified reference material of human urine (GBW 09115) validated its accuracy along with good recoveries (87-102%). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. A novel bridge coupler for SSC coupled cavity linac

    International Nuclear Information System (INIS)

    Yao, C.G.; Chang, C.R.; Funk, W.

    1992-01-01

    A novel magnetically coupled multi-cavity bridge coupler is proposed for SSC Coupled-Cavity-Linac (CCL). The bridge coupler is a five cell disc-loaded waveguide with a small central aperture used for measurement and two large curved coupling slots near the edge on each disc. The two coupling slots on the adjacent disc are rotated 90 degrees in orientation to reduce the direct coupling. This type of structure is capable of producing very large coupling (>10% in our longest bridge coupler). Also because of the small opening on the discs, the high-order-modes are very far (> 300 MHz) above the operating mode. Thus for long bridge couplers, the magnetic coupled structure should provide maximum coupling with minimum mode mixing problems. In this paper both physics and engineering issues of this new bridge coupler are presented. (Author) 5 refs., 2 tabs., 6 figs

  19. Visible high power fiber coupled diode lasers

    Science.gov (United States)

    Köhler, Bernd; Drovs, Simon; Stoiber, Michael; Dürsch, Sascha; Kissel, Heiko; Könning, Tobias; Biesenbach, Jens; König, Harald; Lell, Alfred; Stojetz, Bernhard; Löffler, Andreas; Strauß, Uwe

    2018-02-01

    In this paper we report on further development of fiber coupled high-power diode lasers in the visible spectral range. New visible laser modules presented in this paper include the use of multi single emitter arrays @ 450 nm leading to a 120 W fiber coupled unit with a beam quality of 44 mm x mrad, as well as very compact modules with multi-W output power from 405 nm to 640 nm. However, as these lasers are based on single emitters, power scaling quickly leads to bulky laser units with a lot of optical components to be aligned. We also report on a new approach based on 450 nm diode laser bars, which dramatically reduces size and alignment effort. These activities were performed within the German government-funded project "BlauLas": a maximum output power of 80 W per bar has been demonstrated @ 450 nm. We show results of a 200 μm NA0.22 fiber coupled 35 W source @ 450 nm, which has been reduced in size by a factor of 25 compared to standard single emitter approach. In addition, we will present a 200 μm NA0.22 fiber coupled laser unit with an output power of 135 W.

  20. Closeness, autonomy, equity, and relationship satisfaction in lesbian couples

    NARCIS (Netherlands)

    Schreurs, KMG; Buunk, BP

    1996-01-01

    It is often assumed that in lesbian relationships a high degree of closeness is reached at the expense of autonomy of the partners. The present study among 119 Dutch lesbian couples examined the effect on relational satisfaction of two dimensions of closeness, emotional dependency and intimacy, and

  1. Strong Coupling Cavity QED with Gate-Defined Double Quantum Dots Enabled by a High Impedance Resonator

    Directory of Open Access Journals (Sweden)

    A. Stockklauser

    2017-03-01

    Full Text Available The strong coupling limit of cavity quantum electrodynamics (QED implies the capability of a matterlike quantum system to coherently transform an individual excitation into a single photon within a resonant structure. This not only enables essential processes required for quantum information processing but also allows for fundamental studies of matter-light interaction. In this work, we demonstrate strong coupling between the charge degree of freedom in a gate-defined GaAs double quantum dot (DQD and a frequency-tunable high impedance resonator realized using an array of superconducting quantum interference devices. In the resonant regime, we resolve the vacuum Rabi mode splitting of size 2g/2π=238  MHz at a resonator linewidth κ/2π=12  MHz and a DQD charge qubit decoherence rate of γ_{2}/2π=40  MHz extracted independently from microwave spectroscopy in the dispersive regime. Our measurements indicate a viable path towards using circuit-based cavity QED for quantum information processing in semiconductor nanostructures.

  2. On the coupling of cyclotron motion to ion internal degrees of freedom

    International Nuclear Information System (INIS)

    Dunbar, R.C.

    1979-01-01

    A possibility of significant coupling between gas-phase ion cyclotron motion and two internal angular momentum terms is explored. The first case, coupling with ion spin, is treated via the relativistic Hamiltonian, and found to produce only relativistic perturbations which are entirely negligible. The second case, coupling with ion rotation, is developed via its equivalence to a Stark effect. Small shifts in the cyclotron resonances frequency , ωsub(c) and the appearance of a weak cyclotron resonance at 2ωsub(c) are predicted, but these effects are negligible in general. If the cyclotron frequency is near an ion rotational transition, however, a shift of 10 -5 in cyclotron frequency may be observed, and could provide a means of investigating low-frequency rotational transitions of ions. (Auth.)

  3. On the ionospheric coupling of auroral electric fields

    Directory of Open Access Journals (Sweden)

    G. T. Marklund

    2009-04-01

    Full Text Available The quasi-static coupling of high-altitude potential structures and electric fields to the ionosphere is discussed with particular focus on the downward field-aligned current (FAC region. Results are presented from a preliminary analysis of a selection of electric field events observed by Cluster above the acceleration region. The degree of coupling is here estimated as the ratio between the magnetic field-aligned potential drop, ΔΦII, as inferred from the characteristic energy of upward ion (electron beams for the upward (downward current region and the high-altitude perpendicular (to B potential, ΔΦbot, as calculated by integrating the perpendicular electric field across the structure. For upward currents, the coupling can be expressed analytically, using the linear current-voltage relation, as outlined by Weimer et al. (1985. This gives a scale size dependent coupling where structures are coupled (decoupled above (below a critical scale size. For downward currents, the current-voltage relation is highly non-linear which complicates the understanding of how the coupling works. Results from this experimental study indicate that small-scale structures are decoupled, similar to small-scale structures in the upward current region. There are, however, exceptions to this rule as illustrated by Cluster results of small-scale intense electric fields, correlated with downward currents, indicating a perfect coupling between the ionosphere and Cluster altitude.

  4. Control of objects with a high degree of freedom

    OpenAIRE

    Wang, He

    2012-01-01

    In this thesis, I present novel strategies for controlling objects with high degrees of freedom for the purpose of robotic control and computer animation, including articulated objects such as human bodies or robots and deformable objects such as ropes and cloth. Such control is required for common daily movements such as folding arms, tying ropes, wrapping objects and putting on clothes. Although there is demand in computer graphics and animation for generating such scenes, li...

  5. Moving State Marine SINS Initial Alignment Based on High Degree CKF

    Directory of Open Access Journals (Sweden)

    Yong-Gang Zhang

    2014-01-01

    Full Text Available A new moving state marine initial alignment method of strap-down inertial navigation system (SINS is proposed based on high-degree cubature Kalman filter (CKF, which can capture higher order Taylor expansion terms of nonlinear alignment model than the existing third-degree CKF, unscented Kalman filter and central difference Kalman filter, and improve the accuracy of initial alignment under large heading misalignment angle condition. Simulation results show the efficiency and advantage of the proposed initial alignment method as compared with existing initial alignment methods for the moving state SINS initial alignment with large heading misalignment angle.

  6. Dynamic Coupling Between Respiratory and Cardiovascular System

    Science.gov (United States)

    Censi, Federica; Calcagnini, Giovanni; Cerutti, Sergio

    The analysis of non-linear dynamics of the coupling among interacting quantities can be very useful for understanding the cardiorespiratory and cardiovascular control mechanisms. In this chapter RP is used to detect and quantify the degree of non-linear coupling between respiration and spontaneous rhythms of both heart rate and blood pressure variability signals. RQA turned out to be suitable for a quantitative evaluation of the observed coupling patterns among rhythms, both in simulated and real data, providing different degrees of coupling. The results from the simulated data showed that the increased degree of coupling between the signals was marked by the increase of PR and PD, and by the decrease of ER. When the RQA was applied to experimental data, PD and ER turned out to be the most significant variables, compared to PR. A remarkable finding is the detection of transient 1:2 PL episodes between respiration and cardiovascular variability signals. This phenomenon can be associated to a sub-harmonic synchronization between the two main rhythms of HR and BP variability series.

  7. Reduction of intergranular exchange coupling and grain size for high Ku CoPt-based granular media: Metal-oxide buffer layer and multiple oxide boundary materials

    Science.gov (United States)

    Tham, Kim Kong; Kushibiki, Ryosuke; Kamada, Tomonari; Hinata, Shintaro; Saito, Shin

    2018-05-01

    Investigation of magnetic properties and microstructure of granular media with various multiple oxides as the grain boundary material is reported. Saturation magnetization (Ms), uniaxial magnetocrystalline anisotropy (Ku), and magnetic grain diameter (GD) of the granular media show linear correlation with volume weighted average for melting point (Tm) of each oxides (Tmave). Ku of magnetic grains (Kugrain) shows a trade-off relation with GD that it is a big challenge to satisfy both high Kugrain and small GD by only controlling Tmave. To obtain a granular medium with appropriate Kugrain, GD, and low degree of intergranular exchange coupling, the combination of Tmave control of grain boundary material by mixing oxides and employment of a buffer layer are required. Here the degree of intergranular exchange coupling is estimated from the slope of M-H loop at around coercivity (α). By applying this technique, a typical granular medium with Kugrain of 1.0×107 erg/cm3, GD of 5.1 nm, and α of 1.2 is realized.

  8. Multi-UAV Doppler Information Fusion for Target Tracking Based on Distributed High Degrees Information Filters

    Directory of Open Access Journals (Sweden)

    Hamza Benzerrouk

    2018-03-01

    Full Text Available Multi-Unmanned Aerial Vehicle (UAV Doppler-based target tracking has not been widely investigated, specifically when using modern nonlinear information filters. A high-degree Gauss–Hermite information filter, as well as a seventh-degree cubature information filter (CIF, is developed to improve the fifth-degree and third-degree CIFs proposed in the most recent related literature. These algorithms are applied to maneuvering target tracking based on Radar Doppler range/range rate signals. To achieve this purpose, different measurement models such as range-only, range rate, and bearing-only tracking are used in the simulations. In this paper, the mobile sensor target tracking problem is addressed and solved by a higher-degree class of quadrature information filters (HQIFs. A centralized fusion architecture based on distributed information filtering is proposed, and yielded excellent results. Three high dynamic UAVs are simulated with synchronized Doppler measurement broadcasted in parallel channels to the control center for global information fusion. Interesting results are obtained, with the superiority of certain classes of higher-degree quadrature information filters.

  9. Electron beam gun with kinematic coupling for high power RF vacuum devices

    Science.gov (United States)

    Borchard, Philipp

    2016-11-22

    An electron beam gun for a high power RF vacuum device has components joined by a fixed kinematic coupling to provide both precise alignment and high voltage electrical insulation of the components. The kinematic coupling has high strength ceramic elements directly bonded to one or more non-ductile rigid metal components using a high temperature active metal brazing alloy. The ceramic elements have a convex surface that mates with concave grooves in another one of the components. The kinematic coupling, for example, may join a cathode assembly and/or a beam shaping focus electrode to a gun stem, which is preferably composed of ceramic. The electron beam gun may be part of a high power RF vacuum device such as, for example, a gyrotron, klystron, or magnetron.

  10. Development of high power models of four-slot Annular Coupled Structure

    International Nuclear Information System (INIS)

    Kageyama, T.; Morozumi, Y.; Yoshino, K.; Yamazaki, Y.

    1994-01-01

    A π/2-mode standing-wave linac (f=1.296 GHz) of an Annular Coupled Structure (ACS) has been developed for the 1-GeV proton linac of the Japanese Hadron Project (JHP). This ACS has four coupling slots between accelerating and coupling cells in order to suppress higher order mode mixing with the π/2 coupling mode. High-β(β=v/c=0.78) and low-β(0.52) prototypes were constructed and tested up to each design RF power. Concerning the effect of the coupling slots on the fields of a coupled-cavity linac, it was found that the slot configuration of the side-coupled structure (SCS) tilts the accelerating field. On the other hand, the four-slot configuration of the ACS gives an almost axially symmetric accelerating field to the beam. (author)

  11. Extensions to the coupling coefficient calculations for muon telescopes

    International Nuclear Information System (INIS)

    Baker, C.P.; Humble, J.E.; Duldig, M.L.

    1989-01-01

    The calculation of coupling coefficients for muon telescopes has previously used interpolation from a limited set of asymptotic directions of arrival of primary particles. Furthermore, these calculations have not incorporated curvature of the atmosphere and thus diverge from the true response at zenith angles greater than about 75 degrees. The necessary extensions to calculate coupling coefficients at arbitrary zenith angles are given, including an improved method of incorporating the asymptotic directions of the primary particles. It is shown, using this method, that certain coupling coefficients are highly sensitive to small changes in asymptotic directions for some telescope configurations. 10 refs., 1 fig., 3 tabs

  12. Extensions to the coupling coefficient calculations for muon telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Baker, C P; Humble, J E [Tasmania Univ., Sandy Bay (Australia). Dept. of Physics; Duldig, M L [Dept. of the Arts, Sport, the Environment, Tourism and Territories, Hobart (Australia). Antarctic Div.

    1989-01-01

    The calculation of coupling coefficients for muon telescopes has previously used interpolation from a limited set of asymptotic directions of arrival of primary particles. Furthermore, these calculations have not incorporated curvature of the atmosphere and thus diverge from the true response at zenith angles greater than about 75 degrees. The necessary extensions to calculate coupling coefficients at arbitrary zenith angles are given, including an improved method of incorporating the asymptotic directions of the primary particles. It is shown, using this method, that certain coupling coefficients are highly sensitive to small changes in asymptotic directions for some telescope configurations. 10 refs., 1 fig., 3 tabs.

  13. 360-degrees profilometry using strip-light projection coupled to Fourier phase-demodulation.

    Science.gov (United States)

    Servin, Manuel; Padilla, Moises; Garnica, Guillermo

    2016-01-11

    360 degrees (360°) digitalization of three dimensional (3D) solids using a projected light-strip is a well-established technique in academic and commercial profilometers. These profilometers project a light-strip over the digitizing solid while the solid is rotated a full revolution or 360-degrees. Then, a computer program typically extracts the centroid of this light-strip, and by triangulation one obtains the shape of the solid. Here instead of using intensity-based light-strip centroid estimation, we propose to use Fourier phase-demodulation for 360° solid digitalization. The advantage of Fourier demodulation over strip-centroid estimation is that the accuracy of phase-demodulation linearly-increases with the fringe density, while in strip-light the centroid-estimation errors are independent. Here we proposed first to construct a carrier-frequency fringe-pattern by closely adding the individual light-strip images recorded while the solid is being rotated. Next, this high-density fringe-pattern is phase-demodulated using the standard Fourier technique. To test the feasibility of this Fourier demodulation approach, we have digitized two solids with increasing topographic complexity: a Rubik's cube and a plastic model of a human-skull. According to our results, phase demodulation based on the Fourier technique is less noisy than triangulation based on centroid light-strip estimation. Moreover, Fourier demodulation also provides the amplitude of the analytic signal which is a valuable information for the visualization of surface details.

  14. The frequency and the degree of fusion of the lung on high-resolution CT

    International Nuclear Information System (INIS)

    Shin, Hwan Sik; Kim, Sung Jin; Bae, Il Hun; Song, Kyung Sup; Kim, Joo Chang; Han, Ki Suk; Cha, Sang Hoon; Park, Kil Sun

    2000-01-01

    To evaluate the frequency and degree of fusion of the lung as seen on high-resolution CT (HRCT). In 210 patients high-resolution CT scans from the apex to the diaphragm were obtained at 1 mm collimation and 7 mm interval. We retrospectively analysed the frequency and degree of fusion of the lung bordering each interlobar fissure. Fusion of the lung was defined when fissure appeared without complete lobar separation. The degree of lung fusion was classified as mild (less than 1/3 of the fissure), moderate (greater than 1/3 and less than 2/3 of fissure), or severe (greater than 2/3 of the fissure). In 90 of 210 patients, all fissures were identified. In 73 of these 90 (81.1%), lung fusion was noted, the most frequent site of this being between the right upper and right middle lobe (53.3%) . The least frequent site was between the upper portion of the left upper and left lower lobe (32.2%). Am mild degree of fusion was most frequently found between the right middle and right lower lobe (83.9%0, while a severe degree was most frequent between the right middle and right upper lobe (50.0%), followed by the lingular division and the left lower lobe (41.9%). HRCT can be used to evaluate the frequency and degree of interlobar lung fusion. (author)

  15. Treatment of corneal astigmatism with the new small-incision lenticule extraction (SMILE) laser technique: Is treatment of high degree astigmatism equally accurate, stable and safe as treatment of low degree astigmatism?

    DEFF Research Database (Denmark)

    Hansen, Rasmus Søgaard; Lyhne, Niels; Grauslund, Jakob

    .6%) treated for low astigmatism and four eyes (3.2%) treated for high astigmatism (P=0.02) had lost two or more lines of BSCVA after three months. Conclusion: This study is the first of its kind, and our results indicate that SMILE treatment of high degree astigmatism is equally accurate and stable...... as treatment of low degree astigmatism. More eyes treated for high degree astigmatism lose two or more lines of BSCVA up to three months after surgery. Keywords Refractive surgery, astigmatism, SMILE......Field: Ophthalmology Introduction: SMILE has proven effective in treatment of myopia and low degrees of astigmatism (less than 2 dioptres (D)), but there are no studies on treatment of high degrees of astigmatism (2 or more D). The aim of this study was to compare results after SMILE treatment...

  16. Coupled transverse motion

    International Nuclear Information System (INIS)

    Teng, L.C.

    1989-01-01

    The magnetic field in an accelerator or a storage ring is usually so designed that the horizontal (x) and the vertical (y) motions of an ion are uncoupled. However, because of imperfections in construction and alignment, some small coupling is unavoidable. In this lecture, we discuss in a general way what is known about the behaviors of coupled motions in two degrees-of-freedom. 11 refs., 6 figs

  17. [Coupling coordinated development of ecological-economic system in Loess Plateau].

    Science.gov (United States)

    Zhang, Qing-Feng; Wu, Fa-Qi; Wang, Li; Wang, Jian

    2011-06-01

    Based on system theory, a coupling coordinated development model of ecological-economic system in Loess Plateau was established, and the evaluation criteria and basic types of the coordinated development of the ecological-economic system were proposed. The county-level coupling coordinated development of the ecological-economic system was also discussed, based on the local characteristics. The interactions between the ecological and economic systems in Loess Plateau could be divided into four stages, i.e., seriously disordered development stage, mild-disordered development stage, low-level coordinated development stage, and high level well-coordinated development stage. At each stage, there existed a cyclic process of profit and loss-antagonist-running-dominant-synchronous development. The coupling development degree of the ecological-economic system in Loess Plateau was overall at a lower level, being about 62.7% of the counties at serious disorder, 30.1% of the counties at mild disorder, and 7.1% of the counties at low but coordinated level. The coupling development degree based on the model established in this study could better reflect the current social-economic and ecological environment situations, especially the status of coordination. To fully understand the coupling of ecological-economic system and to adopt appropriate development mode would be of significance to promote the county-level coordinated development in Loess Plateau.

  18. Coupled intertwiner dynamics: A toy model for coupling matter to spin foam models

    OpenAIRE

    Steinhaus, Sebastian

    2015-01-01

    The universal coupling of matter and gravity is one of the most important features of general relativity. In quantum gravity, in particular spin foams, matter couplings have been defined in the past, yet the mutual dynamics, in particular if matter and gravity are strongly coupled, are hardly explored, which is related to the definition of both matter and gravitational degrees of freedom on the discretisation. However extracting this mutual dynamics is crucial in testing the viability of the ...

  19. High degree of sex chromosome differentiation in stickleback fishes

    Directory of Open Access Journals (Sweden)

    Shimada Yukinori

    2011-09-01

    Full Text Available Abstract Background Studies of closely related species with different sex chromosome systems can provide insights into the processes of sex chromosome differentiation and evolution. To investigate the potential utility of molecular markers in studying sex chromosome differentiation at early stages of their divergence, we examined the levels and patterns of genetic differentiation between sex chromosomes in nine-spined (Pungitius pungitius and three-spined sticklebacks (Gasterosteus aculeatus using microsatellite markers. Results A set of novel microsatellite markers spanning the entire length of the sex chromosomes were developed for nine-spined sticklebacks using the sequenced genomes of other fish species. Sex-specific patterns of genetic variability and male-specific alleles were identified at most of these loci, indicating a high degree of differentiation between the X and Y chromosomes in nine-spined sticklebacks. In three-spined sticklebacks, male-specific alleles were detected at some loci confined to two chromosomal regions. In addition, male-specific null alleles were identified at several other loci, implying the absence of Y chromosomal alleles at these loci. Overall, male-specific alleles and null alleles were found over a region spanning 81% of the sex chromosomes in three-spined sticklebacks. Conclusions High levels but distinct patterns of sex chromosome differentiation were uncovered in the stickleback species that diverged 13 million years ago. Our results suggest that the Y chromosome is highly degenerate in three-spined sticklebacks, but not in nine-spined sticklebacks. In general, the results demonstrate that microsatellites can be useful in identifying the degree and patterns of sex chromosome differentiation in species at initial stages of sex chromosome evolution.

  20. Distributed coupling high efficiency linear accelerator

    Science.gov (United States)

    Tantawi, Sami G.; Neilson, Jeffrey

    2016-07-19

    A microwave circuit for a linear accelerator includes multiple monolithic metallic cell plates stacked upon each other so that the beam axis passes vertically through a central acceleration cavity of each plate. Each plate has a directional coupler with coupling arms. A first coupling slot couples the directional coupler to an adjacent directional coupler of an adjacent cell plate, and a second coupling slot couples the directional coupler to the central acceleration cavity. Each directional coupler also has an iris protrusion spaced from corners joining the arms, a convex rounded corner at a first corner joining the arms, and a corner protrusion at a second corner joining the arms.

  1. Efficient synchronization of structurally adaptive coupled Hindmarsh-Rose neurons

    International Nuclear Information System (INIS)

    Moujahid, A.; D'Anjou, A.; Torrealdea, F.J.; Torrealdea, F.

    2011-01-01

    Highlights: → Neural activity might be constrained by a requirement of energy efficiency. → Signaling in synchrony is a normal way to propagate information between neurons. → Quality of synchrony affects the capacity to exchange information and the energy cost. → Adaptive mechanism leads to high degree of synchronization between nonidentical neurons. - Abstract: The use of spikes to carry information between brain areas implies complete or partial synchronization of the neurons involved. The degree of synchronization reached by two coupled systems and the energy cost of maintaining their synchronized behavior is highly dependent on the nature of the systems. For non-identical systems the maintenance of a synchronized regime is energetically a costly process. In this work, we study conditions under which two non-identical electrically coupled neurons can reach an efficient regime of synchronization at low energy cost. We show that the energy consumption required to keep the synchronized regime can be spontaneously reduced if the receiving neuron has adaptive mechanisms able to bring its biological parameters closer in value to the corresponding ones in the sending neuron.

  2. Collisionless coupling of a high- β expansion to an ambient, magnetized plasma. II. Experimental fields and measured momentum coupling

    Science.gov (United States)

    Bonde, Jeffrey; Vincena, Stephen; Gekelman, Walter

    2018-04-01

    The momentum coupled to a magnetized, ambient argon plasma from a high- β, laser-produced carbon plasma is examined in a collisionless, weakly coupled limit. The total electric field was measured by separately examining the induced component associated with the rapidly changing magnetic field of the high- β (kinetic β˜106), expanding plasma and the electrostatic component due to polarization of the expansion. Their temporal and spatial structures are discussed and their effect on the ambient argon plasma (thermal β˜10-2) is confirmed with a laser-induced fluorescence diagnostic, which directly probed the argon ion velocity distribution function. For the given experimental conditions, the electrostatic field is shown to dominate the interaction between the high- β expansion and the ambient plasma. Specifically, the expanding plasma couples energy and momentum into the ambient plasma by pulling ions inward against the flow direction.

  3. Optimization of High-Q Coupled Nanobeam Cavity for Label-Free Sensing

    OpenAIRE

    Yaseen, Mohammad; Yang, Yi-Chun; Shih, Min-Hsiung; Chang, Yia-Chung

    2015-01-01

    We numerically and experimentally investigated the lateral coupling between photonic crystal (PhC) nanobeam (NB) cavities, pursuing high sensitivity and figure of merit (FOM) label-free biosensor. We numerically carried out 3D finite-difference time-domain (3D-FDTD) and the finite element method (FEM) simulations. We showed that when two PhC NB cavities separated by a small gap are evanescently coupled, the variation in the gap width significantly changes the coupling efficiency between the ...

  4. Estimating the degree of identity by descent in consanguineous couples.

    Science.gov (United States)

    Carr, Ian M; Markham, Sir Alexander F; Pena, Sérgio D J

    2011-12-01

    In some clinical and research settings, it is often necessary to identify the true level of "identity by descent" (IBD) between two individuals. However, as the individuals become more distantly related, it is increasingly difficult to accurately calculate this value. Consequently, we have developed a computer program that uses genome-wide SNP genotype data from related individuals to estimate the size and extent of IBD in their genomes. In addition, the software can compare a couple's IBD regions with either the autozygous regions of a relative affected by an autosomal recessive disease of unknown cause, or the IBD regions in the parents of the affected relative. It is then possible to calculate the probability of one of the couple's children suffering from the same disease. The software works by finding SNPs that exclude any possible IBD and then identifies regions that lack these SNPs, while exceeding a minimum size and number of SNPs. The accuracy of the algorithm was established by estimating the pairwise IBD between different members of a large pedigree with varying known coefficients of genetic relationship (CGR). © 2011 Wiley Periodicals, Inc.

  5. Reduction of intergranular exchange coupling and grain size for high Ku CoPt-based granular media: Metal-oxide buffer layer and multiple oxide boundary materials

    Directory of Open Access Journals (Sweden)

    Kim Kong Tham

    2018-05-01

    Full Text Available Investigation of magnetic properties and microstructure of granular media with various multiple oxides as the grain boundary material is reported. Saturation magnetization (Ms, uniaxial magnetocrystalline anisotropy (Ku, and magnetic grain diameter (GD of the granular media show linear correlation with volume weighted average for melting point (Tm of each oxides (Tmave. Ku of magnetic grains (Kugrain shows a trade-off relation with GD that it is a big challenge to satisfy both high Kugrain and small GD by only controlling Tmave. To obtain a granular medium with appropriate Kugrain, GD, and low degree of intergranular exchange coupling, the combination of Tmave control of grain boundary material by mixing oxides and employment of a buffer layer are required. Here the degree of intergranular exchange coupling is estimated from the slope of M-H loop at around coercivity (α. By applying this technique, a typical granular medium with Kugrain of 1.0×107 erg/cm3, GD of 5.1 nm, and α of 1.2 is realized.

  6. High Degree of Autonomy: The Reversion of Hong Kong to Chinese Sovereignty

    National Research Council Canada - National Science Library

    Choyke, Michele

    1998-01-01

    ...) of the People's Republic of China. The Sino-British Joint Declaration on the Question of Hong Kong calls for maintaining Hong Kong's lifestyle and "high degree of autonomy" for fifty years after its transition to the Hong Kong SAR...

  7. Coupling of high-quality-factor optical resonators

    International Nuclear Information System (INIS)

    Salzenstein, Patrice; Henriet, Rémi; Coillet, Aurélien; Chembo, Yanne K; Mortier, Michel; Sérier-Brault, Hélène; Rasoloniaina, Alphonse; Dumeige, Yannick; Féron, Patrice

    2013-01-01

    We improve theoretically and experimentally the problem of the coupling between a high Q-factor resonator and its external coupler. We have observed oscillations of ringing induced by the sweeping of the excitation frequency of an active microsphere. Thanks to this approach, the quality factor of an optical resonator was measured and we obtained Q = 5.8 × 10 8 . (paper)

  8. Coupled processes in repository sealing

    International Nuclear Information System (INIS)

    Case, J.B.; Kelsall, P.C.

    1985-01-01

    The significance of coupled processes in repository sealing is evaluated. In most repository designs, shaft seals will be located in areas of relatively low temperature perturbation, in which case the coupling of temperature with stress and permeability may be less significant than the coupling between stress and permeability that occurs during excavation. Constitutive relationships between stress and permeability are reviewed for crystalline rock and rocksalt. These provide a basis for predicting the development of disturbed zones near excavations. Field case histories of the degree of disturbance are presented for two contrasting rock types - Stripa granite and Southeastern New Mexico rocksalt. The results of field investigations in both rock types confirm that hydraulic conductivity or permeability is stress dependent, and that shaft seal performance may be related to the degree that stresses are perturbed and restored near the seal

  9. From globally coupled maps to complex-systems biology

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, Kunihiko, E-mail: kaneko@complex.c.u-tokyo.ac.jp [Research Center for Complex Systems Biology, Graduate School of Arts and Sciences, The University of Tokyo 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2015-09-15

    Studies of globally coupled maps, introduced as a network of chaotic dynamics, are briefly reviewed with an emphasis on novel concepts therein, which are universal in high-dimensional dynamical systems. They include clustering of synchronized oscillations, hierarchical clustering, chimera of synchronization and desynchronization, partition complexity, prevalence of Milnor attractors, chaotic itinerancy, and collective chaos. The degrees of freedom necessary for high dimensionality are proposed to equal the number in which the combinatorial exceeds the exponential. Future analysis of high-dimensional dynamical systems with regard to complex-systems biology is briefly discussed.

  10. Heat-to-heat variability of irradiation creep and swelling of HT9 irradiated to high neutron fluence at 400-600{degrees}C

    Energy Technology Data Exchange (ETDEWEB)

    Toloczko, M.B.; Garner, F.A. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-10-01

    Irradiation creep data on ferritic/martensitic steels are difficult and expensive to obtain, and are not available for fusion-relevant neutron spectra and displacement rates. Therefore, an extensive creep data rescue and analysis effort is in progress to characterize irradiation creep of ferritic/martensitic alloys in other reactors and to develop a methodology for applying it to fusion applications. In the current study, four tube sets constructed from three nominally similar heats of HT9 subjected to one of two heat treatments were constructed as helium-pressurized creep tubes and irradiated in FFTF-MOTA at four temperatures between 400 and 600{degrees}C. Each of the four heats exhibited a different stress-free swelling behavior at 400{degrees}C, with the creep rate following the swelling according to the familiar B{sub o} + DS creep law. No stress-free swelling was observed at the other three irradiation temperatures. Using a stress exponent of n = 1.0 as the defining criterion, {open_quotes}classic{close_quotes} irradiation creep was found at all temperatures, but, only over limited stress ranges that decreased with increasing temperature. The creep coefficient B{sub o} is a little lower ({approx}50%) than that observed for austenitic steel, but the swelling-creep coupling coefficient D is comparable to that of austenitic steels. Primary transient creep behavior was also observed at all temperatures except 400{degrees}C, and thermal creep behavior was found to dominate the deformation at high stress levels at 550 and 600{degrees}C.

  11. Critical features of coupling parameter in synchronization of small world neural networks

    International Nuclear Information System (INIS)

    Li Yanlong; Ma Jun; Xu Wenke; Li Hongbo; Wu Min

    2008-01-01

    The critical features of a coupling parameter in the synchronization of small world neural networks are investigated. A power law decay form is observed in this spatially extended system, the larger linked degree becomes, the larger critical coupling intensity. There exists maximal and minimal critical coupling intensity for synchronization in the extended system. An approximate synchronization diagram has been constructed. In the case of partial coupling, a primary result is presented about the critical coupling fraction for various linked degree of networks

  12. Advanced Output Coupling for High Power Gyrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Read, Michael [Calabazas Creek Research, Inc., San Mateo, CA (United States); Ives, Robert Lawrence [Calabazas Creek Research, Inc., San Mateo, CA (United States); Marsden, David [Calabazas Creek Research, Inc., San Mateo, CA (United States); Collins, George [Calabazas Creek Research, Inc., San Mateo, CA (United States); Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Guss, William [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Lohr, John [General Atomics, La Jolla, CA (United States); Neilson, Jeffrey [Lexam Research, Redwood City, CA (United States); Bui, Thuc [Calabazas Creek Research, Inc., San Mateo, CA (United States)

    2016-11-28

    The Phase II program developed an internal RF coupler that transforms the whispering gallery RF mode produced in gyrotron cavities to an HE11 waveguide mode propagating in corrugated waveguide. This power is extracted from the vacuum using a broadband, chemical vapor deposited (CVD) diamond, Brewster angle window capable of transmitting more than 1.5 MW CW of RF power over a broad range of frequencies. This coupling system eliminates the Mirror Optical Units now required to externally couple Gaussian output power into corrugated waveguide, significantly reducing system cost and increasing efficiency. The program simulated the performance using a broad range of advanced computer codes to optimize the design. Both a direct coupler and Brewster angle window were built and tested at low and high power. Test results confirmed the performance of both devices and demonstrated they are capable of achieving the required performance for scientific, defense, industrial, and medical applications.

  13. Analysis of the coupling coordination between transportation infrastructure investment and economic development in Hubei province

    Directory of Open Access Journals (Sweden)

    Wenxia Zhai

    2017-06-01

    Full Text Available The relationship between transportation infrastructure investment and regional economic growth has been the focus of domestic and foreign academic research. Using the models of coupling degree and coupling coordination degree, this paper calculated the coupling degree and coupling coordination degree between the comprehensive level of transportation infrastructure investment and economic development in Hubei province and its 17 cities, and analyzed its temporal and spatial characteristics. The result showed that, from 2001 to 2013, the coupling and coupling coordination between transportation infrastructure investment and economic development in Hubei province were on a steady rise in the time sequence characteristics. It experienced the upgrade from the uncoordinated – nearly uncoordinated – barely coordinated – intermediately coordinated stages. In the year of 2013, the coupling and coupling coordination of transportation infrastructure investment and economic development in the 17 prefecture-level cities of Hubei Province showed a very uneven spatial difference. Good coordination, primary coordination, barely coordinate, and barely in-coordination are distributed in the province. The average coordination degree of the 17 prefecture-level cities in Hubei is relatively low, and there is a negative tend to expand the difference. This study has confirmed the relationship between transportation infrastructure investment and the economic development to be in an interactive coupling and coordination, but in different regions and different stages, the degree of coordination has obvious spatial and temporal differences.

  14. Chaotic Motion of Nonlinearly Coupled Quintic Oscillators | Adeloye ...

    African Journals Online (AJOL)

    With a fixed energy, we investigate the motion of two nonlinearly coupled quintic oscillators for various values of the coupling strength with the aid of the Poincare surface of section. It is observed that chaotic motion sets in for coupling strength as low as 0.001. The degree of chaoticity generally increases as the coupling ...

  15. Gravity- and non-gravity-mediated couplings in multiple-field inflation

    International Nuclear Information System (INIS)

    Bernardeau, Francis

    2010-01-01

    Mechanisms for the generation of primordial non-Gaussian metric fluctuations in the context of multiple-field inflation are reviewed. As long as kinetic terms remain canonical, it appears that nonlinear couplings inducing non-Gaussianities can be split into two types. The extension of the one-field results to multiple degrees of freedom leads to gravity-mediated couplings that are ubiquitous but generally modest. Multiple-field inflation offers however the possibility of generating non-gravity-mediated coupling in isocurvature directions that can eventually induce large non-Gaussianities in the metric fluctuations. The robustness of the predictions of such models is eventually examined in view of a case study derived from a high-energy physics construction.

  16. Coupled processes in NRC high-level waste research

    International Nuclear Information System (INIS)

    Costanzi, F.A.

    1987-01-01

    The author discusses NRC research effort in support of evaluating license applications for disposal of nuclear waste and for promulgating regulations and issuing guidance documents on nuclear waste management. In order to do this they fund research activities at a number of laboratories, academic institutions, and commercial organizations. One of our research efforts is the coupled processes study. This paper discusses interest in coupled processes and describes the target areas of research efforts over the next few years. The specific research activities relate to the performance objectives of NRC's high-level waste (HLW) regulation and the U.S. Environmental Protection Agency (EPA) HLW standard. The general objective of the research program is to ensure the NRC has a sufficient independent technical base to make sound regulatory decisions

  17. The coupled process laboratory test of highly compacted bentonite

    International Nuclear Information System (INIS)

    Shen Zhenyao; Li Guoding; Li Shushen; Wang Chengzu

    2004-01-01

    Highly compacted bentonite blocks have been heated and hydrated in the laboratory in order to simulate the thermo-hydro-mechanical (THM) coupled processes of buffer material in a high-level radioactive waste (HLW) repository. The experiment facility, which is composed of experiment barrel, heated system, high pressure water input system, temperature measure system, water content measure system and swelling stress system, is introduced in this paper. The steps of the THM coupled experiment are also given out in detail. There are total 10 highly compacted bentonite blocks used in this test. Experimental number 1-4 are the tests with the heater and the hydrated process, which temperature distribution vs. time and final moisture distribution are measured. Experimental number 5-8 are the tests with the heater and without the hydrated process, which temperature distribution vs. time and final moisture distribution are measured. Experimental number 9-10 are the tests with the heater and the hydrated process, which temperature distribution vs. time, final moisture distribution and the swelling stress distribution at some typical points vs. time are measured. The maximum test time is nearly 20 days and the minimum test time is only 8 hours. The results show that the temperature field is little affected by hydration process and stress condition, but moisture transport and stress distribution are a little affected by the thermal gradient. The results also show that the water head difference is the mainly driving force of hydration process and the swelling stress is mainly from hydration process. It will great help to understand better about heat and mass transfer in porous media and the THM coupled process in actual HLW disposal. (author)

  18. Insights into Sonogashira cross-coupling by high-throughput kinetics and descriptor modeling

    NARCIS (Netherlands)

    an der Heiden, M.R.; Plenio, H.; Immel, S.; Burello, E.; Rothenberg, G.; Hoefsloot, H.C.J.

    2008-01-01

    A method is presented for the high-throughput monitoring of reaction kinetics in homogeneous catalysis, running up to 25 coupling reactions in a single reaction vessel. This method is demonstrated and validated on the Sonogashira reaction, analyzing the kinetics for almost 500 coupling reactions.

  19. More mental health problems after divorce in couples with high pre-divorce alcohol consumption than in other divorced couples: results from the HUNT-study.

    Science.gov (United States)

    Rognmo, Kamilla; Torvik, Fartein A; Idstad, Mariann; Tambs, Kristian

    2013-09-17

    Divorce is associated with mental health problems, and heavy drinking is related to higher risk of divorce. Less is known about the effects of divorce in couples where one or both drinks heavily. There are, however, reasons to expect different consequences of divorce in heavy risk using couples compared to other couples. Spouses of abusers may experience the divorce as a relief, whereas abusers may find it extra difficult to be left single. The aim of the study is to compare the effect of divorce on mental health in heavy drinking couples to the effect in couples who drink less. Registry data were matched with data from the Nord-Trøndelag Health Study (HUNT 1 (T1) and 2 (T2)), enabling longitudinal analyses of approximately 11,000 couples. Interaction terms between 1) alcohol use on T1 and divorce between T1 and T2 (11 year time lag), and 2) alcohol use on T1 and time since divorce at T2 for all divorced couples were tested to examine changes in mental health between T1 and T2 for a) spouses of high-risk compared to low-risk users, and b) high-risk compared to low-risk users themselves. Data were analyzed using multivariate analysis of variance. There was a general effect of divorce on change in mental health between T1 and T2. We observed a significantly stronger worsening in mental health in female high-risk users and their spouses than in divorced low-risk users and their spouses. The results also suggest that the strain after divorce lasts longer in women with a high alcohol consumption and their spouses. Divorce seems to affect couples where one or both drink heavily more than couples with a low consumption. Also there was some evidence of a slower healing of mental health problems after divorce in alcohol exposed couples than in other couples. The results only reached significance for female high consumers and their spouses, but due to limited statistical power, safe conclusions about gender specific effects cannot be drawn.

  20. How couples choose vasectomy.

    Science.gov (United States)

    Schehl, M

    1997-01-01

    A study conducted by AVSC International between 1992 and 1995 found that couples around the world go through a highly similar decision-making process when they choose vasectomy as their family planning methods. Study findings are based upon in-depth, qualitative interviews with couples using vasectomy in Bangladesh, Mexico, Kenya, and Rwanda, where the prevalence of vasectomy is relatively low, and Sri Lanka and the US, where it is relatively high. 218 separate interviews were conducted with male and female partners. Concerns about the woman's health were cited by respondents in each country as reasons to cease childbearing and to opt for vasectomy as the means to achieving that end. Also, almost all respondents mentioned varying degrees of financial hardship as contributing to their decision to end childbearing. These findings highlight the concept of partnership in relationships and family planning decision-making, and demonstrate the importance of going beyond traditional stereotypes about gender roles in decision-making. Social influences and the potential risks of using other forms of contraception also contributed to the choice of using vasectomy. The decision-making process and lessons learned are discussed.

  1. Fast and high-fidelity entangling gate through parametrically modulated longitudinal coupling

    Directory of Open Access Journals (Sweden)

    Baptiste Royer

    2017-05-01

    Full Text Available We investigate an approach to universal quantum computation based on the modulation of longitudinal qubit-oscillator coupling. We show how to realize a controlled-phase gate by simultaneously modulating the longitudinal coupling of two qubits to a common oscillator mode. In contrast to the more familiar transversal qubit-oscillator coupling, the magnitude of the effective qubit-qubit interaction does not rely on a small perturbative parameter. As a result, this effective interaction strength can be made large, leading to short gate times and high gate fidelities. We moreover show how the gate infidelity can be exponentially suppressed with squeezing and how the entangling gate can be generalized to qubits coupled to separate oscillators. Our proposal can be realized in multiple physical platforms for quantum computing, including superconducting and spin qubits.

  2. Transition from High School to Associate Degree Nursing Education: A Qualitative Study

    Science.gov (United States)

    Mitchell, Kathy Jessee

    2012-01-01

    Nursing is facing a critical shortage and retention of nursing students is of paramount importance. Much research has been completed related to retention in nursing education and student success, but there is very little in current literature related to issues associated with the transition from high school to associate degree nursing (ADN)…

  3. Ideas and perspectives: how coupled is the vegetation to the boundary layer?

    Directory of Open Access Journals (Sweden)

    M. G. De Kauwe

    2017-10-01

    Full Text Available Understanding the sensitivity of transpiration to stomatal conductance is critical to simulating the water cycle. This sensitivity is a function of the degree of coupling between the vegetation and the atmosphere and is commonly expressed by the decoupling factor. The degree of coupling assumed by models varies considerably and has previously been shown to be a major cause of model disagreement when simulating changes in transpiration in response to elevated CO2. The degree of coupling also offers us insight into how different vegetation types control transpiration fluxes, which is fundamental to our understanding of land–atmosphere interactions. To explore this issue, we combined an extensive literature summary from 41 studies with estimates of the decoupling coefficient estimated from FLUXNET data. We found some notable departures from the values previously reported in single-site studies. There was large variability in estimated decoupling coefficients (range 0.05–0.51 for evergreen needleleaf forests. This is a result that was broadly supported by our literature review but contrasts with the early literature which suggests that evergreen needleleaf forests are generally well coupled. Estimates from FLUXNET indicated that evergreen broadleaved forests were the most tightly coupled, differing from our literature review and instead suggesting that it was evergreen needleleaf forests. We also found that the assumption that grasses would be strongly decoupled (due to vegetation stature was only true for high precipitation sites. These results were robust to assumptions about aerodynamic conductance and, to a lesser extent, energy balance closure. Thus, these data form a benchmarking metric against which to test model assumptions about coupling. Our results identify a clear need to improve the quantification of the processes involved in scaling from the leaf to the whole ecosystem. Progress could be made with targeted measurement campaigns at

  4. Development and optimization of a high temperature coupling system thermoanalyzer/mass spectrometer

    International Nuclear Information System (INIS)

    Jagdfeld, H.J.

    1983-11-01

    The development of a high temperature coupling system was accomplished to carry out thermodynamic investigations during glass melting to solidify highly radioactive fission products into glass at a temperature up to 1200 0 C. The actual problem consisted of the fact that the gas species evaporating from the melter have to pass without condensation or without change of their composition a multistage pressure reducing system to enter the analysator unit of the mass spectrometer in the high vacuum. With the systems, offered at present, this is only possible up to approximately 450 0 C. The development of a new high temperature coupling included investigations of the gas dynamics, raw materials and thermic behaviour. (orig./EF) [de

  5. Assessment of high precision, high accuracy Inductively Coupled Plasma-Optical Emission Spectroscopy to obtain concentration uncertainties less than 0.2% with variable matrix concentrations

    International Nuclear Information System (INIS)

    Rabb, Savelas A.; Olesik, John W.

    2008-01-01

    The ability to obtain high precision, high accuracy measurements in samples with complex matrices using High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy (HP-ICP-OES) was investigated. The Common Analyte Internal Standard (CAIS) procedure was incorporated into the High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy method to correct for matrix-induced changes in emission intensity ratios. Matrix matching and standard addition approaches to minimize matrix-induced errors when using High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy were also assessed. The High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy method was tested with synthetic solutions in a variety of matrices, alloy standard reference materials and geological reference materials

  6. Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures

    International Nuclear Information System (INIS)

    Rutqvist, Jonny; Blanco-Martin, Laura; Molins, Sergi; Trebotich, David; Birkholzer, Jens

    2015-01-01

    In this report, we present FY2015 progress by Lawrence Berkeley National Laboratory (LBNL) related to modeling of coupled thermal-hydrological-mechanical-chemical (THMC) processes in salt and their effect on brine migration at high temperatures. This is a combined milestone report related to milestone Salt R&D Milestone ''Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures'' (M3FT-15LB0818012) and the Salt Field Testing Milestone (M3FT-15LB0819022) to support the overall objectives of the salt field test planning.

  7. Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, Jonny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Blanco-Martin, Laura [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Molins, Sergi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Trebotich, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Birkholzer, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-09-01

    In this report, we present FY2015 progress by Lawrence Berkeley National Laboratory (LBNL) related to modeling of coupled thermal-hydrological-mechanical-chemical (THMC) processes in salt and their effect on brine migration at high temperatures. This is a combined milestone report related to milestone Salt R&D Milestone “Modeling Coupled THM Processes and Brine Migration in Salt at High Temperatures” (M3FT-15LB0818012) and the Salt Field Testing Milestone (M3FT-15LB0819022) to support the overall objectives of the salt field test planning.

  8. A tilted fiber-optic plate coupled CCD detector for high resolution neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jongyul; Cho, Gyuseong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Jongyul; Hwy, Limchang; Kim, Taejoo; Lee, Kyehong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Seungwook [Pusan National Univ., Pusan (Korea, Republic of)

    2013-05-15

    One of these efforts is that a tilted scintillator geometry and lens coupled CCD detector for neutron imaging system were used to improve spatial resolution in one dimension. The increased spatial resolution in one dimension was applied to fuel cell study. However, a lens coupled CCD detector has lower sensitivity than a fiber-optic plate coupled CCD detector due to light loss. In this research, a tilted detector using fiber-optic plate coupled CCD detector was developed to improve resolution and sensitivity. In addition, a tilted detector can prevent an image sensor from direct radiation damage. Neutron imaging has been used for fuel cell study, lithium ion battery study, and many scientific applications. High quality neutron imaging is demanded for more detailed studies of applications, and spatial resolution should be considered to get high quality neutron imaging. Therefore, there were many efforts to improve spatial resolution.

  9. Linking structure and vibrational mode coupling using high-resolution infrared spectroscopy: A comparison of gauche and trans 1-chloro-2-fluoroethane

    Science.gov (United States)

    Miller, C. Cameron; Stone, Stephen C.; Philips, Laura A.

    1995-01-01

    The high-resolution infrared spectrum of 1-chloro-2-fluoroethane in a molecular beam was collected over the 2975-2994 cm-1 spectral region. The spectral region of 2975-2981 cm-1 contains a symmetric C-H stretching vibrational band of the gauche conformer containing the 35Cl isotope. The spectral region of 2985-2994 cm-1 contains three vibrational bands of the trans conformer. Two of the three bands are assigned as an antisymmetric C-H stretch of each of the two different chlorine isotopes. The third band is assigned as a symmetric C-H stretch of the 35Cl isotope. The gauche conformer of 1-chloro-2-fluoroethane showed doublet patterns similar to those previously observed in 1,2-difluoroethane. The model for 1,2-difluoroethane is further refined in the present work. These refinements suggest that the coupling dark state in 1,2-difluoroethane is composed of 1 quantum C-H bend, 1 quantum C-C stretch, and 12 quanta of torsion. For 1-chloro-2-fluoroethane the dark state could not be identified due to a small data set. The trans conformer of 1-chloro-2-fluoroethane showed no evidence of mode coupling in the three vibrational bands. Including 2-fluoroethanol in this series of molecules, the extent of vibrational mode coupling did not correlate with the density of states available for coupling. Therefore, density of states alone is insufficient to explain the observed trend. A correlation was observed between the degree of intramolecular interaction and vibrational mode coupling.

  10. A soft-switching coupled inductor bidirectional DC-DC converter with high-conversion ratio

    Science.gov (United States)

    Chao, Kuei-Hsiang; Jheng, Yi-Cing

    2018-01-01

    A soft-switching bidirectional DC-DC converter is presented herein as a way to improve the conversion efficiency of a photovoltaic (PV) system. Adoption of coupled inductors enables the presented converter not only to provide a high-conversion ratio but also to suppress the transient surge voltage via the release of the energy stored in leakage flux of the coupled inductors, and the cost can kept down consequently. A combined use of a switching mechanism and an auxiliary resonant branch enables the converter to successfully perform zero-voltage switching operations on the main switches and improves the efficiency accordingly. It was testified by experiments that our proposed converter works relatively efficiently in full-load working range. Additionally, the framework of the converter intended for testifying has high-conversion ratio. The results of a test, where a generating system using PV module array coupled with batteries as energy storage device was used as the low-voltage input side, and DC link was used as high-voltage side, demonstrated our proposed converter framework with high-conversion ratio on both high-voltage and low-voltage sides.

  11. Simulation of Octopus Arm Based on Coupled CPGs

    OpenAIRE

    Juan Tian; Qiang Lu

    2015-01-01

    The octopus arm has attracted many researchers’ interests and became a research hot spot because of its amazing features. Several dynamic models inspired by an octopus arm are presented to realize the structure with a large number of degrees of freedom. The octopus arm is made of a soft material introducing high-dimensionality, nonlinearity, and elasticity, which makes the octopus arm difficult to control. In this paper, three coupled central pattern generators (CPGs) are built and a 2-dimens...

  12. Personal, family and social functioning among older couples concordant and discordant for high-risk alcohol consumption.

    Science.gov (United States)

    Moos, Rudolf H; Schutte, Kathleen K; Brennan, Penny L; Moos, Bernice S

    2011-02-01

    This study compares the personal, family and social functioning of older husbands and wives concordant or discordant for high-risk alcohol consumption and identifies predictors of changes in concordance and high-risk consumption. Three groups of couples were identified at baseline and followed 10 years later: (i) concordant couples in which husbands and wives engaged in low-risk alcohol consumption (n = 54); (ii) concordant couples in which husbands and wives engaged in high-risk alcohol consumption (n = 38); and (iii) discordant couples in which one partner engaged in high-risk alcohol consumption and the other partner did not (n = 75). At each follow-up, husbands and wives completed an inventory that assessed their personal, family and social functioning. Compared to the low-risk concordant group, husbands and wives in the high-risk concordant group were more likely to rely on tension-reduction coping, reported more friend approval of drinking, and were less involved in religious activities; however, they did not differ in the quality of the spousal relationship. The frequency of alcohol consumption declined among husbands in discordant couples, but not among husbands in concordant couples. Predictors of high-risk drinking included tension-reduction coping, friend approval of drinking and, for husbands, their wives' level of drinking. High-risk and discordant alcohol consumption do not seem to be linked to decrements in family functioning among older couples in long-term stable marriages. The predictors of heavy alcohol consumption among older husbands and wives identify points of intervention that may help to reduce their high-risk drinking. © 2010 Society for the Study of Addiction. No claim to US government works.

  13. Isolation and characterization of inulin with a high degree of polymerization from roots of Stevia rebaudiana (Bert.) Bertoni.

    Science.gov (United States)

    Lopes, Sheila M S; Krausová, Gabriela; Rada, Vojtěch; Gonçalves, José E; Gonçalves, Regina A C; de Oliveira, Arildo J B

    2015-06-26

    The polysaccharide inulin has great importance in the food and pharmaceutical industries. The degree of polymerization (DP) of inulin influences important properties, such as, solubility, thermal stability, sweetness power and prebiotic activity. Molecules with a high degree of polymerization are obtained through physical techniques for enrichment of the inulin chains because they are not commonly obtained from plants extract. Gas chromatography/Mass Spectrometry and (1)H Nuclear Magnetic Resonance analysis showed that inulin from Stevia rebaudiana roots has a degree of polymerization (DPn 28) higher than the value of DPn 12-15 for inulins from other plant species. Furthermore, the methodology of freeze/thaw to enrich the chains allowed us to increase the DP, similarly to other methodologies used for the enrichment of inulin chains. The prebiotic assays confirm that inulin from S. rebaudiana has a high DP. The combined use of these molecules with low degree of polymerization fructans seems to be advantageous to prolong the prebiotic effect in the colon. Our results suggest that S. rebaudiana roots are a promising source of high degree polymerization inulins. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Conceptual design and economic evaluation about the coupling of high power PWRs and desalination system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Ho; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Hyeon Min; Heo, Gyun Young [Kyung Hee Univ., Yongin (Korea, Republic of)

    2012-03-15

    Both electricity and fresh water become basic human needs in modern days. This paper describes the coupling methods of high power pressurized water reactors and desalination system, and evaluates the economics of coupling systems. OPR1000 designed by Korea was chosen for the reference reactor. Because MED (Mulct-Effect Distillation) with TVC (Thermal Vapor Compressor) have been evaluated as an effective desalination system for high power reactors, it was used for the reference desalination method in simulation. In order to simulate the secondary circuit of PWRs with heat exchangers for MED-TVC, PEPSE program which is normally used for performance evaluation of power system efficiencies was used. The coupling of OPR1000 and desalination systems were set under the restriction it had to make as small changes as possible. From the results PEPSE simulation, the economics of the coupling systems were calculates using equations form DEEP4.0 (Desalination Economic Evaluation Program) which was developed by IAEA because Deep simulates just two simple couplings which are back pressure and condensation/extraction. In the secondary circuit simulation seven coupling cases were set and outlet powers to heat exchanger for desalination were varied to be dependent on the thermohydraulic conditions on each part. The results of changed electrical power generation were calculated with the thermal outputs for desalination. It is concluded that two coupling method using the steam from high-pressure turbine have high performance and are economical among the simulated cases. The first one is to add a heat exchanger on the branch from high-pressure turbine into moisture separator and the other is on the branch into feedwater heating parts. It proves desalination plants can be added to current high power PWRs.

  15. A Path to High-Efficiency Optical Coupling for HIRMES

    Science.gov (United States)

    Miller, Timothy M.; Brown, Ari-David; Costen, Nicholas; Franz, David; Kutyrev, Alexander; Mikula, Vilem; Miller, Kevin H.; Moseley, S. Harvey; Oxborrow, Joseph; Rostem, Karwan; Wollack, Edward J.

    2018-05-01

    The high-resolution mid-infrared spectrometer (HIRMES) under development for Stratospheric Observatory for Infrared Astronomy is an instrument operating in the 25-122 μm spectral range with a spectral resolution R = Δλ/λ 100,000 and has two absorber-coupled transition edge sensor bolometric detector focal planes. We have developed novel NbTiN low-stress absorber coatings which have the required optical impedance across the HIRMES operating band. The low intrinsic stress of these coatings allow for a peak-to-valley corrugation amplitude coupled bolometric detector applications, because it helps in controlling the optical loading from out-of-band radiation. We also discuss a novel method for integrating a wedged-reflective absorber termination to the detector array.

  16. New approach to the determination phosphorothioate oligonucleotides by ultra high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Studzińska, Sylwia; Mounicou, Sandra; Szpunar, Joanna; Łobiński, Ryszard; Buszewski, Bogusław

    2015-01-15

    This text presents a novel method for the separation and detection of phosphorothioate oligonucleotides with the use of ion pair ultra high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry The research showed that hexafluoroisopropanol/triethylamine based mobile phases may be successfully used when liquid chromatography is coupled with such elemental detection. However, the concentration of both HFIP and TEA influences the final result. The lower concentration of HFIP, the lower the background in ICP-MS and the greater the sensitivity. The method applied for the analysis of serum samples was based on high resolution inductively coupled plasma mass spectrometry. Utilization of this method allows determination of fifty times lower quantity of phosphorothioate oligonucleotides than in the case of quadrupole mass analyzer. Monitoring of (31)P may be used to quantify these compounds at the level of 80 μg L(-1), while simultaneous determination of sulfur is very useful for qualitative analysis. Moreover, the results presented in this paper demonstrate the practical applicability of coupling LC with ICP-MS in determining phosphorothioate oligonucleotides and their metabolites in serum within 7 min with a very good sensitivity. The method was linear in the concentration range between 0.2 and 3 mg L(-1). The limit of detection was in the range of 0.07 and 0.13 mg L(-1). Accuracy varied with concentration, but was in the range of 3%. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. High-power fiber-coupled pump lasers for fiber lasers

    Science.gov (United States)

    Kasai, Yohei; Aizawa, Takuya; Tanaka, Daiichiro

    2018-02-01

    We present high-power fiber-coupled pump modules utilized effectively for ultra-high power single-mode (SM) fiber lasers. Maximum output power of 392 W was achieved at 23 A for 915 nm pump, and 394 W for 976 nm pump. Fiber core diameter is 118 μm and case temperature is 25deg. C. Polarization multiplexing technique was newly applied to our optical system. High-reliability of the laser diodes (LD) at high-power operation has been demonstrated by aging tests. Advanced package structure was developed that manages uncoupled light around input end of the fiber. 800 hours continuous drive with uncoupled light power of 100 W has been achieved.

  18. Highly polarized light emission by isotropic quantum dots integrated with magnetically aligned segmented nanowires

    International Nuclear Information System (INIS)

    Uran, Can; Erdem, Talha; Guzelturk, Burak; Perkgöz, Nihan Kosku; Jun, Shinae; Jang, Eunjoo; Demir, Hilmi Volkan

    2014-01-01

    In this work, we demonstrate a proof-of-concept system for generating highly polarized light from colloidal quantum dots (QDs) coupled with magnetically aligned segmented Au/Ni/Au nanowires (NWs). Optical characterizations reveal that the optimized QD-NW coupled structures emit highly polarized light with an s-to p-polarization (s/p) contrast as high as 15:1 corresponding to a degree of polarization of 0.88. These experimental results are supported by the finite-difference time-domain simulations, which demonstrate the interplay between the inter-NW distance and the degree of polarization.

  19. Degree-degree correlations in random graphs with heavy-tailed degrees

    NARCIS (Netherlands)

    Hofstad, van der R.W.; Litvak, N.

    2014-01-01

    Mixing patterns in large self-organizing networks, such as the Internet, the World Wide Web, social, and biological networks are often characterized by degree-degree dependencies between neighboring nodes. In assortative networks, the degree-degree dependencies are positive (nodes with similar

  20. Degree-Degree Dependencies in Random Graphs with Heavy-Tailed Degrees

    NARCIS (Netherlands)

    van der Hofstad, Remco; Litvak, Nelly

    2014-01-01

    Mixing patterns in large self-organizing networks, such as the Internet, the World Wide Web, social, and biological networks are often characterized by degree-degree dependencies between neighboring nodes. In assortative networks, the degree-degree dependencies are positive (nodes with similar

  1. High precision redundant robotic manipulator

    International Nuclear Information System (INIS)

    Young, K.K.D.

    1998-01-01

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space is disclosed. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degrees of freedom. Each of the embodiments utilize a first selective compliant assembly robot arm (SCARA) configuration to provide high stiffness in the vertical plane, a second SCARA configuration to provide high stiffness in the horizontal plane. The seven degree of freedom embodiment also utilizes kinematic redundancy to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector or link of the manipulator. These additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw and roll. The seven degrees of freedom embodiment uses one revolute point per degree of freedom. For each of the revolute joints, a harmonic gear coupled to an electric motor is introduced, and together with properly designed based servo controllers provide an end point repeatability of less than 10 microns. 3 figs

  2. Strong-coupling interaction in high-Tc superconductors

    International Nuclear Information System (INIS)

    Ray, D.K.

    1991-01-01

    Extensive experimental and theoretical work have been done to understand the mechanisms of superconductivity. Until 1986 when Bednorz and Muller discovered superconductivity in the copper oxide perovskite, the principal mechanism was found to be electron-phonon interaction and the characteristics of superconductivity vary depending on the strength of the electron-phonon interaction and the electronic structure. The essential characteristic of these conventional superconductors could be divided into two groups: wide band metals with low density of states N(E F ) at the Fermi energy E F and a rather weak electron-phonon coupling V obeying the universal characteristics of the BCS theory and narrow d band metals, compounds, and alloys with high values of N(E F ), electron-phonon coupling V and non negligible Coulomb interaction between the electrons. In this paper a short summary and the important results of these theories are discussed. The inherent limitations of these theories based on electron-phonon interaction will be discussed. The authors indicate the major characteristics of the new superconductors. These characteristics are difficult to explain on the basis of either the conventional electron-phonon theory or theories based on magnetic interactions alone

  3. Correlative degree and collective side ward flow of final state particles in high energy heavy ion collisions

    International Nuclear Information System (INIS)

    Zhang Weigang

    1999-01-01

    A concept of correlative degree is proposed. Using the method of particle-group correlation's function, the effects of the particles with different correlative degrees on collective side ward flow are studied for 1.2A GeV Ar + Bal 2 collisions at the Bevalac stream chamber. The studies indicate that correlative degree is an important parameter on describing collective side ward flow properties. The minority of correlative particles (or fragments) with larger correlative degrees can produce the effect arising from the collective side ward flow, but the effect arising from high-order collective flow correlations can not be dominated by these minority of particles (or fragments). It is results from the collective contribution of the majority of collective particles (or fragments) with various correlative degrees

  4. Obtaining water with a high degree of purity by using reverse osmosis

    Directory of Open Access Journals (Sweden)

    Nicolae Chirilă

    2011-12-01

    Full Text Available In this paper, we used the method of reverse osmosis in order to obtain water with a high degree of purity. For this aim, we used the TKA 20-120ECO device. We completed physic-chemical determinations for the water of supply, as well as for the water obtained after the osmosis process. The results that we obtained are relevant and interesting.

  5. High Power Combiner/Divider with Coupled Lines for Broadband Applications

    Science.gov (United States)

    2017-03-20

    novel isolation structure will also be presented. I. INTRODUCTION Power divider/combiners are traditionally used in the development of high power ...a novel Gysel divider/combiner structure have been demonstrated. The divider/combiner are applicable to various high- power , broadband radar, EW...Gysel Power Divider With Arbitrary Power Ratios and Filtering Responses Using Coupling Structure ,” IEEE Transactions on Microwave Theory and Tech., vol

  6. Reducing sexual risk behavior among high-risk couples in Northern India.

    Science.gov (United States)

    Jones, Deborah; Bagga, Rashmi; Nehra, Ritu; Deepika; Sethi, Sunil; Walia, Kamini; Kumar, Mahendra; Villar-Loubet, Olga; Lopez, Maria; Weiss, Stephen M

    2013-09-01

    With a population of 1.1 billion, India is considered to be a country in which effective prevention interventions could contain the development of a human immunodeficiency virus (HIV) epidemic. Heterosexual transmission accounts for 85 % of the extant HIV infections. This study sought to assess the feasibility of conducting a group, culturally tailored behavioral intervention and its impact on sexual barrier use, self-efficacy, knowledge, conflict resolution, and coping among high-risk heterosexual couples in Northern India. This pilot study was conducted at the Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India from February 2008 to January 2009. Thirty sexually active high-risk couples were drawn from a convenience sample of PGIMER patients attending infectious disease and family planning clinics. Couples participated in 1 month of three weekly gender-concordant behavioral intervention groups and were individually administered assessments preintervention and post-intervention. The intervention was tailored to the Northern Indian context and addressed sexual barrier use, human immunodeficiency virus (HIV)/sexually transmitted infection transmission, and cognitive behavioral skill building focusing on sexual negotiation and communication. The participants had a mean age of 32 years (men) and 29 years (women), and the majority had at least 10 years of education. At baseline, the majority reported inconsistent condom use (knowledge, and women increased their use of positive coping tactics. The results highlight the potential to successfully utilize a group intervention to discuss sensitive issues such as sexual risk behavior among both men and women. Strategies to improve condom use and communication without increasing intimate partner violence in high-risk couples may be an important adjunct to preventing the development of a generalized epidemic in India.

  7. Pathways to a Four-Year Degree: Determinants of Degree Completion among Socioeconomically Disadvantaged Students.

    Science.gov (United States)

    Cabrera, Alberto F.; Burkum, Kurt R.; La Nasa, Steven M.

    The High School Sophomore Cohort of 1980 followed nine different pathways to a 4-year college degree. These paths were formed by a combination of different levels of academic preparation secured in high school and the first type of postsecondary institution attended. The pathway most likely to lead to a 4-year degree is one defined by acquiring…

  8. Circuit electromechanics with single photon strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Zheng-Yuan, E-mail: zyxue@scnu.edu.cn; Yang, Li-Na [Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Zhou, Jian, E-mail: jianzhou8627@163.com [Department of Electronic Communication Engineering, Anhui Xinhua University, Hefei 230088 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China)

    2015-07-13

    In circuit electromechanics, the coupling strength is usually very small. Here, replacing the capacitor in circuit electromechanics by a superconducting flux qubit, we show that the coupling among the qubit and the two resonators can induce effective electromechanical coupling which can attain the strong coupling regime at the single photon level with feasible experimental parameters. We use dispersive couplings among two resonators and the qubit while the qubit is also driven by an external classical field. These couplings form a three-wave mixing configuration among the three elements where the qubit degree of freedom can be adiabatically eliminated, and thus results in the enhanced coupling between the two resonators. Therefore, our work constitutes the first step towards studying quantum nonlinear effect in circuit electromechanics.

  9. High-performance coupled poro-hydro-mechanical models to resolve fluid escape pipes

    Science.gov (United States)

    Räss, Ludovic; Makhnenko, Roman; Podladchikov, Yury

    2017-04-01

    Field observations and laboratory experiments exhibit inelastic deformation features arising in many coupled settings relevant to geo-applications. These irreversible deformations and their specific patterns suggest a rather ductile or brittle mechanism, such as viscous creep or micro cracks, taking place on both geological (long) and human (short) timescales. In order to understand the underlying mechanisms responsible for these deformation features, there is a current need to accurately resolve the non-linearities inherent to strongly coupled physical processes. Among the large variety of modelling tools and softwares available nowadays in the community, very few are capable to efficiently solve coupled systems with high accuracy in both space and time and run efficiently on modern hardware. Here, we propose a robust framework to solve coupled multi-physics hydro-mechanical processes on very high spatial and temporal resolution in both two and three dimensions. Our software relies on the Finite-Difference Method and a pseudo-transient scheme is used to converge to the implicit solution of the system of poro-visco-elasto-plastic equations at each physical time step. The rheology including viscosity estimates for major reservoir rock types is inferred from novel lab experiments and confirms the ease of flow of sedimentary rocks. Our results propose a physical mechanism responsible for the generation of high permeability pathways in fluid saturated porous media and predict their propagation in rates observable on operational timescales. Finally, our software scales linearly on more than 5000 GPUs.

  10. Why do different people choose different university degrees? Motivation and the choice of degree

    Directory of Open Access Journals (Sweden)

    Anya eSkatova

    2014-11-01

    Full Text Available Different people choose which undergraduate degree to study at the university for different reasons. To date, there have been limited attempts to identify individual differences in motivation that drive the undergraduate degree choice. We identified that people choose university degrees for four reasons: career concerns (Career, intrinsic interest (Interest in the subject, an opportunity to help others (Helping and because they are looking for an easy option into higher education (Loafing. We investigated whether these motivation apply to the choice of undergraduate degree in two samples: (1 undergraduate (N = 989 and (2 prospective (N = 896 students. We developed the Motivations Influencing Course Choice (MICC questionnaire to measure these motivations. Scales of Helping, Career, Loafing and Interest showed good psychometric properties, showed validity with respect to general life goals and personality traits, and predicted actual and prospective degree choices. We demonstrated that medical degrees were chosen due to a mixture of Helping and Career, while engineering degrees were associated with Career and low interest in the degree. The choice of art and humanities degrees was driven by Interest and low concern about future career, accompanied with high Loafing. We also demonstrated gender differences: females were high in Helping (both samples and Interest (only in undergraduate sample motivation, while males scored higher in Career (only in undergraduate sample and Loafing (both samples. The findings can feed into both theoretical accounts of proximal motivation as well as help to improve degree programmes at universities and provide better career advice.

  11. Why do different people choose different university degrees? Motivation and the choice of degree.

    Science.gov (United States)

    Skatova, Anya; Ferguson, Eamonn

    2014-01-01

    Different people choose undergraduate degrees to study at university for different reasons. To date, there have been limited attempts to identify individual differences in motivation that drive undergraduate degree choice. We identified that people choose university degrees for four reasons: career concerns (Career), intrinsic interest in the subject (Interest), an opportunity to help others (Helping) and because they are looking for an easy option to get into higher education (Loafing). We investigated whether these motivations apply to the choice of undergraduate degree in two samples: (1) undergraduate (N = 989) and (2) prospective (N = 896) students. We developed the Motivations Influencing Course Choice (MICC) questionnaire to measure these motivations. Scales of Helping, Career, Loafing, and Interest showed good psychometric properties, showed validity with respect to general life goals and personality traits, and predicted actual and prospective degree choices. We demonstrated that medical degrees were chosen due to a mixture of Helping and Career, while engineering degrees were associated with Career and low Interest in the degree. The choice of arts and humanities degrees was driven by Interest and low concern about future career, accompanied with high Loafing. We also demonstrated gender differences: females were high in Helping (both samples) and Interest (only in the undergraduate sample) motivation, while males scored higher in Career (only in the undergraduate sample) and Loafing (both samples). The findings can feed into both theoretical accounts of proximal motivation as well as provide help to improve degree programmes at universities and support better career advice.

  12. High performance waveguide-coupled Ge-on-Si linear mode avalanche photodiodes.

    Science.gov (United States)

    Martinez, Nicholas J D; Derose, Christopher T; Brock, Reinhard W; Starbuck, Andrew L; Pomerene, Andrew T; Lentine, Anthony L; Trotter, Douglas C; Davids, Paul S

    2016-08-22

    We present experimental results for a selective epitaxially grown Ge-on-Si separate absorption and charge multiplication (SACM) integrated waveguide coupled avalanche photodiode (APD) compatible with our silicon photonics platform. Epitaxially grown Ge-on-Si waveguide-coupled linear mode avalanche photodiodes with varying lateral multiplication regions and different charge implant dimensions are fabricated and their illuminated device characteristics and high-speed performance is measured. We report a record gain-bandwidth product of 432 GHz for our highest performing waveguide-coupled avalanche photodiode operating at 1510nm. Bit error rate measurements show operation with BER-12, in the range from -18.3 dBm to -12 dBm received optical power into a 50 Ω load and open eye diagrams with 13 Gbps pseudo-random data at 1550 nm.

  13. Collapsing spherical star in Scalar-Einstein-Gauss-Bonnet gravity with a quadratic coupling

    Science.gov (United States)

    Chakrabarti, Soumya

    2018-04-01

    We study the evolution of a self interacting scalar field in Einstein-Gauss-Bonnet theory in four dimension where the scalar field couples non minimally with the Gauss-Bonnet term. Considering a polynomial coupling of the scalar field with the Gauss-Bonnet term, a self-interaction potential and an additional perfect fluid distribution alongwith the scalar field, we investigate different possibilities regarding the outcome of the collapsing scalar field. The strength of the coupling and choice of the self-interaction potential serves as the pivotal initial conditions of the models presented. The high degree of non-linearity in the equation system is taken care off by using a method of invertibe point transformation of anharmonic oscillator equation, which has proven itself very useful in recent past while investigating dynamics of minimally coupled scalar fields.

  14. Interqubit coupling mediated by a high-excitation-energy quantum object

    NARCIS (Netherlands)

    Ashhab, S.; Niskanen, A.O.; Harrabi, K.; Nakamura, Y.; Picot, T.; De Groot, P.C.; Harmans, C.J.P.M.; Mooij, J.E.; Nori, F.

    2008-01-01

    We consider a system composed of two qubits and a high excitation energy quantum object used to mediate coupling between the qubits. We treat the entire system quantum mechanically and analyze the properties of the eigenvalues and eigenstates of the total Hamiltonian. After reproducing well known

  15. Coupling an Ensemble of Electrons on Superfluid Helium to a Superconducting Circuit

    Directory of Open Access Journals (Sweden)

    Ge Yang

    2016-03-01

    Full Text Available The quantized lateral motional states and the spin states of electrons trapped on the surface of superfluid helium have been proposed as basic building blocks of a scalable quantum computer. Circuit quantum electrodynamics allows strong dipole coupling between electrons and a high-Q superconducting microwave resonator, enabling such sensitive detection and manipulation of electron degrees of freedom. Here, we present the first realization of a hybrid circuit in which a large number of electrons are trapped on the surface of superfluid helium inside a coplanar waveguide resonator. The high finesse of the resonator allows us to observe large dispersive shifts that are many times the linewidth and make fast and sensitive measurements on the collective vibrational modes of the electron ensemble, as well as the superfluid helium film underneath. Furthermore, a large ensemble coupling is observed in the dispersive regime during experiment, and it shows excellent agreement with our numeric model. The coupling strength of the ensemble to the cavity is found to be ≈1  MHz per electron, indicating the feasibility of achieving single electron strong coupling.

  16. Extremely high-brightness kW-class fiber coupled diode lasers with wavelength stabilization

    Science.gov (United States)

    Huang, Robin K.; Chann, Bien; Glenn, John D.

    2011-06-01

    TeraDiode has produced ultra-high brightness fiber-coupled direct diode lasers. A fiber-coupled direct diode laser with a power level of 1,040 W from a 200 μm core diameter, 0.18 numerical aperture (NA) output fiber at a single center wavelength was demonstrated. This was achieved with a novel beam combining and shaping technique using COTS diode lasers. The fiber-coupled output corresponds to a Beam Parameter Product (BPP) of 18 mm-mrad and is the lowest BPP kW-class direct diode laser yet reported. The laser has been used to demonstrate laser cutting and welding of steel sheet metal up to 6.65 mm thick. Higher brightness fiber-coupled diode lasers, including a module with 418 W of power coupled to a 100 μm, 0.15 NA fiber, have also been demonstrated.

  17. Effect of galvanic coupling between overpack materials for high-level nuclear waste containers

    International Nuclear Information System (INIS)

    Dunn, D.S.; Cragnolino, G.A.; Sridhar, N.

    1998-01-01

    The effect of environmental parameters and area ratio on the galvanic protection of Alloy 825 by A516 steel was studied. A simplified model was used to calculate the potential and corrosion current density of the bimetallic couple as a function of the galvanic coupling efficiency. Galvanic corrosion tests were performed to gain confidence in the calculated values. Both the calculations and laboratory testing indicate that, with highly efficient coupling, the potential of the galvanic couple is maintained below the repassivation potential for Alloy 825 in chloride-containing solutions. As a result, the initiation of localized corrosion on Alloy 825 is prevented. The formation of oxides, scales, and corrosion product layers between the barriers is shown to reduce the efficiency of the galvanic couple, which may result in conditions under which the localized corrosion of the inner corrosion resistant barrier can occur

  18. Metric elasticity in a collapsing star: Gravitational radiation coupled to torsional motion

    International Nuclear Information System (INIS)

    Gerlach, U.H.; Scott, J.F.

    1986-01-01

    Torsional oscillatory matter motion as well as differential rotation couple via the linearized Einstein field equations to the gravitational degrees of freedom. For an arbitrary spherically symmetric background, such as that of a wildly pulsating or a catastrophically collapsing star, we exhibit (a) the strain tensor and (b) the corresponding stress-energy tensor. It is found that in the star there are two elasticity tensors. One expresses the familiar elasticity of matter, the other expresses the elasticity of the geometry. This metric elasticity is responsible for coupling the gravitational and matter degrees of freedom. The two coupled scalar wave equations for these degrees of freedom are exhibited. Also exhibited are their characteristics as well as the junction conditions for their solutions across any spherical surface of discontinuity

  19. High-power laser diodes with high polarization purity

    Science.gov (United States)

    Rosenkrantz, Etai; Yanson, Dan; Peleg, Ophir; Blonder, Moshe; Rappaport, Noam; Klumel, Genady

    2017-02-01

    Fiber-coupled laser diode modules employ power scaling of single emitters for fiber laser pumping. To this end, techniques such as geometrical, spectral and polarization beam combining (PBC) are used. For PBC, linear polarization with high degree of purity is important, as any non-perfectly polarized light leads to losses and heating. Furthermore, PBC is typically performed in a collimated portion of the beams, which also cancels the angular dependence of the PBC element, e.g., beam-splitter. However, we discovered that single emitters have variable degrees of polarization, which depends both on the operating current and far-field divergence. We present data to show angle-resolved polarization measurements that correlate with the ignition of high-order modes in the slow-axis emission of the emitter. We demonstrate that the ultimate laser brightness includes not only the standard parameters such as power, emitting area and beam divergence, but also the degree of polarization (DoP), which is a strong function of the latter. Improved slow-axis divergence, therefore, contributes not only to high brightness but also high beam combining efficiency through polarization.

  20. High Costs, Uncertain Benefits: What Do Americans without a College Degree Think about Postsecondary Education?

    Science.gov (United States)

    Kelly, Andrew P.

    2015-01-01

    The path to economic mobility increasingly runs through postsecondary education. Although the combination of rising tuition prices and a difficult labor market have raised questions about the value of education after high school, degree and certificate holders are still better off than those with just a high school diploma. As a group, young…

  1. A study on high speed coupling design for wind turbine using a finite element analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyoung Woo; Kang, Jong Hun [Dept. of Mechatronics Engineering, Jungwon University, Geosan (Korea, Republic of); Han, Jeong Young [Pusan Educational Center for Computer Aided Machine Design, Pusan University, Busan (Korea, Republic of)

    2016-08-15

    The purpose of this study is to design a high speed coupling for 3 MW wind turbines and evaluate its structural stability. A basic analysis was performed to assess the structural stability of two materials, SPS6 steel plate and a composite material (Glass7628, Glass/Epoxy), in relation to misalignment in the axial and radial directions. The entire model was analyzed for a high speed coupling based on the SPS6 steel plate, which was found to have higher stability among the two materials, and safety factors were estimated for various levels of power delivery. To test the proposed high speed coupling design, a performance test was carried out to verify the stability of the final product.

  2. A study on high speed coupling design for wind turbine using a finite element analysis

    International Nuclear Information System (INIS)

    Lee, Hyoung Woo; Kang, Jong Hun; Han, Jeong Young

    2016-01-01

    The purpose of this study is to design a high speed coupling for 3 MW wind turbines and evaluate its structural stability. A basic analysis was performed to assess the structural stability of two materials, SPS6 steel plate and a composite material (Glass7628, Glass/Epoxy), in relation to misalignment in the axial and radial directions. The entire model was analyzed for a high speed coupling based on the SPS6 steel plate, which was found to have higher stability among the two materials, and safety factors were estimated for various levels of power delivery. To test the proposed high speed coupling design, a performance test was carried out to verify the stability of the final product

  3. Fluid lipid bilayers: Intermonolayer coupling and its thermodynamic manifestations

    DEFF Research Database (Denmark)

    Hansen, Per Lyngs; Miao, Ling; Ipsen, John Hjorth

    1998-01-01

    of a phenomenological model that describes the necessary types of degrees of freedom and their interplay, which reflects different modes of intermonolayer coupling. Furthermore, we investigate! based on the phenomenological model, the manifestations of the intermonolayer coupling both in the lateral ordering processes...

  4. The impact of the degree of application of e-commerce on operational performance among Taiwans high-tech manufacturers

    Directory of Open Access Journals (Sweden)

    Yi-Chan Chung

    2013-11-01

    Full Text Available This study probes the correlation of types of operational strategy, degrees of organisational learning, types of organisational culture, the degree of the application of e-commerce, and operational performance among high-tech firms in Taiwan. The data was collected by questionnaires distributed via mail to senior supervisors at high-tech firms in six industries at three Taiwanese science parks. The results showed that a higher degree of e-commerce application leads to a significant and positive effect on operational performance. This study suggests that, in order to upgrade operational performance, firms should enhance their organisational learning and e-commerce, along with their rational, hierarchical, consensual, and developmental cultures, and the execution of prospector and defender strategies.

  5. Results of a Master's degree program for high-school teachers

    Science.gov (United States)

    Cocke, W. J.

    1993-05-01

    Starting in the summer of 1990, the Astronomy Department at the University of Arizona began a 3-year summer program for upgrading the skills of high-school and middle-school science teachers. The program granted Master's degrees in Astronomy to the 33 teachers that completed the program this past summer. The teachers received tuition waivers and stipends to cover living expenses. The funding came mostly from the National Science Foundation, but the University of Arizona cost-shared at the 15% level. About half of the teachers were from Arizona, and the rest came from out-of-state. Although minorities were encouraged to apply, we had few minority applicants, and there were no Afro-Americans and only one Hispanic in the program. The content of the courses was heavily slanted towards mathematics and the physical sciences. The math level went up to vector calculus and linear partial differential equations, and there was a heavy emphasis on physics and astrophysics. Astronomy turned out to be a good umbrella under which to strengthen the teachers' knowledge of the physical sciences. One of the weak points in the program was the pace at which we introduced new material to the teachers. The summer sessions were short and very intense, and the teachers often found themselves with insufficient time to digest the information. This was offset to some degree by the high rate of cooperative learning that the teachers exhibited. The program seems to have been a great success, and the teachers report that their higher level of understanding is very useful to them in the classroom, and the astronomy content provided an excellent source of new demonstrations and projects. We present the results of a final survey, in which we ask the teachers to summarize their thoughts about the program and its effectiveness.

  6. Coupled intertwiner dynamics: A toy model for coupling matter to spin foam models

    Science.gov (United States)

    Steinhaus, Sebastian

    2015-09-01

    The universal coupling of matter and gravity is one of the most important features of general relativity. In quantum gravity, in particular spin foams, matter couplings have been defined in the past, yet the mutual dynamics, in particular if matter and gravity are strongly coupled, are hardly explored, which is related to the definition of both matter and gravitational degrees of freedom on the discretization. However, extracting these mutual dynamics is crucial in testing the viability of the spin foam approach and also establishing connections to other discrete approaches such as lattice gauge theories. Therefore, we introduce a simple two-dimensional toy model for Yang-Mills coupled to spin foams, namely an Ising model coupled to so-called intertwiner models defined for SU (2 )k. The two systems are coupled by choosing the Ising coupling constant to depend on spin labels of the background, as these are interpreted as the edge lengths of the discretization. We coarse grain this toy model via tensor network renormalization and uncover an interesting dynamics: the Ising phase transition temperature turns out to be sensitive to the background configurations and conversely, the Ising model can induce phase transitions in the background. Moreover, we observe a strong coupling of both systems if close to both phase transitions.

  7. Transient voltage sharing in series-coupled high voltage switches

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1992-07-01

    Full Text Available For switching voltages in excess of the maximum blocking voltage of a switching element (for example, thyristor, MOSFET or bipolar transistor such elements are often coupled in series - and additional circuitry has to be provided to ensure equal voltage sharing. Between each such series element and system ground there is a certain parasitic capacitance that may draw a significant current during high-speed voltage transients. The "open" switch is modelled as a ladder network. Analy­sis reveals an exponential progression in the distribution of the applied voltage across the elements. Overstressing thus oc­curs in some of the elements at levels of the total voltage that are significantly below the design value. This difficulty is overcome by grading the voltage sharing circuitry, coupled in parallel with each element, in a prescribed manner, as set out here.

  8. An Event to Encourage High School Students to Pursue College Degrees in Physics and Math

    Science.gov (United States)

    Bukiet, Bruce; Thomas, Gordon

    2003-04-01

    We discuss a Math and Physics Day for high school students and teachers, with hands-on activities and seminars involving mathematics and physics. Participants also learn about careers for those who go on to major in physics and mathematics in college. The New York State Section of the APS has provided generous support for this workshop through its Outreach grant program. Approximately a dozen high schools and 100 students attend each year. The program, which runs from 9:15 AM until 2:15 PM, includes an introduction to undergraduate degree programs in Mathematics, Statistics, Optics, Actuarial Science and Applied Physics, a group physics experiment/contest, brief talks over lunch by speakers from industry who have degrees in Math or Physics, and an afternoon seminar. Teachers earn Professional Development credit.

  9. Magnetically coupled high-gain Y-source isolated DC/DC converter

    DEFF Research Database (Denmark)

    Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede

    2014-01-01

    A new form of magnetically coupled DC/DC converter is proposed for medium power applications (250 W to 2 kW), requiring a high-voltage gain, short inductive charging time and galvanic isolation. The proposed converter can be realised using a unique Y-source impedance network and a two-switch push...

  10. Coupling a QFT to a TQFT and duality

    International Nuclear Information System (INIS)

    Kapustin, Anton; Seiberg, Nathan

    2014-01-01

    We consider coupling an ordinary quantum field theory with an infinite number of degrees of freedom to a topological field theory. On ℝ d the new theory differs from the original one by the spectrum of operators. Sometimes the local operators are the same but there are different line operators, surface operators, etc. The effects of the added topological degrees of freedom are more dramatic when we compactify ℝ d , and they are crucial in the context of electric-magnetic duality. We explore several examples including Dijkgraaf-Witten theories and their generalizations both in the continuum and on the lattice. When we couple them to ordinary quantum field theories the topological degrees of freedom allow us to express certain characteristic classes of gauge fields as integrals of local densities, thus simplifying the analysis of their physical consequences

  11. Single-mode very wide tunability in laterally coupled semiconductor lasers with electrically controlled reflectivities

    Science.gov (United States)

    Griffel, Giora; Chen, Howard Z.; Grave, Ilan; Yariv, Amnon

    1991-04-01

    The operation of a novel multisection structure comprised of laterally coupled gain-guided semiconductor lasers is demonstrated. It is shown that tunable single longitudinal mode operation can be achieved with a high degree of frequency selectivity. The device has a tuning range of 14.5 nm, the widest observed to date in a monolithic device.

  12. A fast high-precision six-degree-of-freedom relative position sensor

    Science.gov (United States)

    Hughes, Gary B.; Macasaet, Van P.; Griswold, Janelle; Sison, Claudia A.; Lubin, Philip; Meinhold, Peter; Suen, Jonathan; Brashears, Travis; Zhang, Qicheng; Madajian, Jonathan

    2016-03-01

    Lasers are commonly used in high-precision measurement and profiling systems. Some laser measurement systems are based on interferometry principles, and others are based on active triangulation, depending on requirements of the application. This paper describes an active triangulation laser measurement system for a specific application wherein the relative position of two fixed, rigid mechanical components is to be measured dynamically with high precision in six degrees of freedom (DOF). Potential applications include optical systems with feedback to control for mechanical vibration, such as target acquisition devices with multiple focal planes. The method uses an array of several laser emitters mounted on one component. The lasers are directed at a reflective surface on the second component. The reflective surface consists of a piecewise-planar pattern such as a pyramid, or more generally a curved reflective surface such as a hyperbolic paraboloid. The reflected spots are sensed at 2-dimensional photodiode arrays on the emitter component. Changes in the relative position of the emitter component and reflective surface will shift the location of the reflected spots within photodiode arrays. Relative motion in any degree of freedom produces independent shifts in the reflected spot locations, allowing full six-DOF relative position determination between the two component positions. Response time of the sensor is limited by the read-out rate of the photodiode arrays. Algorithms are given for position determination with limits on uncertainty and sensitivity, based on laser and spot-sensor characteristics, and assuming regular surfaces. Additional uncertainty analysis is achievable for surface irregularities based on calibration data.

  13. Coupled Tort-TD/CTF Capability for high-fidelity LWR core calculations - 321

    International Nuclear Information System (INIS)

    Christienne, M.; Avramova, M.; Perin, Y.; Seubert, A.

    2010-01-01

    This paper describes the developed coupling scheme between TORT-TD and CTF. TORT-TD is a time-dependent 3D discrete ordinates neutron transport code. TORT-TD is utilized for high-fidelity reactor core neutronics calculations while CTF is providing the thermal-hydraulics feedback information. CTF is an improved version of the advanced thermal-hydraulic sub-channel code COBRA-TF, which is widely used for best-estimate evaluations of LWR safety margins. CTF is a transient code based on a separated flow representation of the two-phase flow. The coupled code TORT-TD/CTF allows 3D pin-by-pin analyses of transients in few energy groups and anisotropic scattering by solving the time-dependent transport equation using the unconditionally stable implicit method. Steady-state and transient test cases, based on the OECD/NRC PWR MOX/UO 2 Core Transient Benchmark, have been calculated. The steady state cases are based on a quarter core model while the transient test case models a control rod ejection transient in a small PWR mini-core fuel assembly arrangement. The obtained results with TORT-TD/CTF are verified by a code-to-code comparison with the previously developed NEM/CTF and TORT-TD/ATHLET coupled code systems. The performed comparative analysis indicates the applicability and high-fidelity potential of the TORT-TD/CTF coupling. (authors)

  14. Mathematical modelling of the destruction degree of cancer under the influence of a RF hyperthermia

    Science.gov (United States)

    Paruch, Marek; Turchan, Łukasz

    2018-01-01

    The article presents the mathematical modeling of the phenomenon of artificial hyperthermia which is caused by the interaction of an electric field. The electric field is induced by the applicator positioned within the biological tissue with cancer. In addition, in order to estimate the degree of tumor destruction under the influence of high temperature an Arrhenius integral has been used. The distribution of electric potential in the domain considered is described by the Laplace system of equations, while the temperature field is described by the Pennes system of equations. These problems are coupled by source function being the additional component in the Pennes equation and resulting from the electric field action. The boundary element method is applied to solve the coupled problem connected with the heating of biological tissues.

  15. High-resolution coupled physics solvers for analysing fine-scale nuclear reactor design problems

    Science.gov (United States)

    Mahadevan, Vijay S.; Merzari, Elia; Tautges, Timothy; Jain, Rajeev; Obabko, Aleksandr; Smith, Michael; Fischer, Paul

    2014-01-01

    An integrated multi-physics simulation capability for the design and analysis of current and future nuclear reactor models is being investigated, to tightly couple neutron transport and thermal-hydraulics physics under the SHARP framework. Over several years, high-fidelity, validated mono-physics solvers with proven scalability on petascale architectures have been developed independently. Based on a unified component-based architecture, these existing codes can be coupled with a mesh-data backplane and a flexible coupling-strategy-based driver suite to produce a viable tool for analysts. The goal of the SHARP framework is to perform fully resolved coupled physics analysis of a reactor on heterogeneous geometry, in order to reduce the overall numerical uncertainty while leveraging available computational resources. The coupling methodology and software interfaces of the framework are presented, along with verification studies on two representative fast sodium-cooled reactor demonstration problems to prove the usability of the SHARP framework. PMID:24982250

  16. Coupled vibrations in horizontal and vertical rotor-bearings systems

    OpenAIRE

    Luneno, Jean-Claude

    2010-01-01

    For dynamical systems having several degrees of freedom, motion in one direction can induce motion in the other and/or vice versa. This means that there is a certain coupling between these two motions. Coupling can in some cases be a source of instability that causes self-excited vibrations in rotating machinery. In modeling hydropower rotors, couplings other than those that are the result of gyroscopic effect are normally not considered. This is due to the complexity of the reasons for coupl...

  17. Coupled vibrations in horizontal and vertical rotor-bearing systems

    OpenAIRE

    Luneno, Jean-Claude

    2011-01-01

    For dynamical systems having several degrees of freedom, motion in one direction can induce motion in the other. This means that there is a certain coupling between these two motions. Coupling can in some cases be a source of instability that causes self-excited vibrations in rotating machinery. In classical modeling of rotor systems, couplings other than those that are the result of gyroscopic effect are normally not considered. This is due to thecomplexity of the reasons for coupling which ...

  18. Traders' behavioral coupling and market phase transition

    Science.gov (United States)

    Ma, Rong; Zhang, Yin; Li, Honggang

    2017-11-01

    Traditional economic theory is based on the assumption that traders are completely independent and rational; however, trading behavior in the real market is often coupled by various factors. This paper discusses behavioral coupling based on the stock index in the stock market, focusing on the convergence of traders' behavior, its effect on the correlation of stock returns and market volatility. We find that the behavioral consensus in the stock market, the correlation degree of stock returns, and the market volatility all exhibit significant phase transitions with stronger coupling.

  19. High degree of genetic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus).

    Science.gov (United States)

    Defaveri, Jacquelin; Shikano, Takahito; Shimada, Yukinori; Merilä, Juha

    2013-09-01

    Populations of widespread marine organisms are typically characterized by a low degree of genetic differentiation in neutral genetic markers, but much less is known about differentiation in genes whose functional roles are associated with specific selection regimes. To uncover possible adaptive population divergence and heterogeneous genomic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus), we used a candidate gene-based genome-scan approach to analyse variability in 138 microsatellite loci located within/close to (<6 kb) functionally important genes in samples collected from ten geographic locations. The degree of genetic differentiation in markers classified as neutral or under balancing selection-as determined with several outlier detection methods-was low (F(ST) = 0.033 or 0.011, respectively), whereas average FST for directionally selected markers was significantly higher (F(ST) = 0.097). Clustering analyses provided support for genomic and geographic heterogeneity in selection: six genetic clusters were identified based on allele frequency differences in the directionally selected loci, whereas four were identified with the neutral loci. Allelic variation in several loci exhibited significant associations with environmental variables, supporting the conjecture that temperature and salinity, but not optic conditions, are important drivers of adaptive divergence among populations. In general, these results suggest that in spite of the high degree of physical connectivity and gene flow as inferred from neutral marker genes, marine stickleback populations are strongly genetically structured in loci associated with functionally relevant genes. © 2013 John Wiley & Sons Ltd.

  20. Couple characteristics and outcome of therapy in vaginismus.

    Science.gov (United States)

    Munasinghe, Thiloma; Goonaratna, Colvin; de Silva, Padmal

    2004-06-01

    To describe couple characteristics and outcome of therapy in vaginismus. A prospective before-after intervention descriptive study. Department of Physiology, Faculty of Medicine, Colombo, Sri Lanka. Fifty six couples with vaginismus, mostly self referrals and referrals from gynaecologists and general practitioners, were treated with a standard cognitive behaviour therapy protocol with before-after assessments of the degree of vaginismus and individual partner self-ratings of the relationship and psychological status (GHQ-30). Success at the end of the therapy was equated to the absence of or only mild vaginismus and, improvement in the couple relationship and psychological status scores. Twenty seven (48%) of the 52 (93%) couples with non-consummation reported failure of coitus following previous non-surgical and surgical interventions. Love marriages (70%), frequent attempts at sex (75%, 3 or 4 times/week) and sexual arousal (women = 86%, men = 89%) characterised couples. Ten men developed sexual problems, mostly erectile failure and premature ejaculation secondarily. Couple therapy enabled penetrative sex in 45 (80.3%). The single prognostic indicator of outcome was the degree of vaginismus at first visit, those with mild and moderate vaginismus (77%) being significantly more likely to establish coitus (p0.01) but the psychological status remained unchanged. Dropouts and referrals for psychiatric and marital counselling failed to complete therapy. Couple sex therapy is effective in the management of vaginismus. Health professionals, especially gynaecologists and general practitioners, need to be aware of the problem and the satisfactory outcome of sex therapy.

  1. Internal multi-scale multi-physics coupled system for high fidelity simulation of light water reactors

    International Nuclear Information System (INIS)

    Ivanov, A.; Sanchez, V.; Stieglitz, R.; Ivanov, K.

    2014-01-01

    Highlights: • The current paper focuses on a optimized method for performing coupled Monte-Carlo/thermal–hydraulics calculations. • Innovative on-the-fly method for supplying the temperature and density distributions is presented. • Convergence acceleration method is presented. It is proven applicable by generalizing the Robbins-Monro theorem. • Tallying is optimized by using collision probability estimator for the power profile estimation. - Abstract: In order to increase the accuracy and the degree of spatial and energy resolution of core design studies, coupled 3D neutronic (multi-group deterministic and continuous energy Monte-Carlo) and 3D thermal–hydraulic (CFD and subchannel) codes are being developed worldwide. At KIT, both deterministic and Monte-Carlo codes were coupled with subchannel codes and applied to predict the safety-related design parameters such as minimal critical power ratio (MCPR), maximal cladding and fuel temperature, departure from nuclide boiling ratio (DNBR). These coupling approaches were revised and considerably improved. Innovative method of internal on-the-fly thermal feedback interchange between the codes was implemented. It no longer relies on explicit material definitions and allows the modeling of temperature and density distributions based on the cell coordinates. In contrast to all existing coupled schemes, this method uses only standard MCNP geometry input and requires only proper definition of the geometrical dimensions. The initial material definition is arbitrary and is determined on-the-fly during the neutron transport by the thermal–hydraulic feedback. Another key issue addressed is the optimal application of parallel computing and the implementation of less time consuming tally estimators. Using multi-processor computer architectures and implementing collision density flux estimator, it is possible to reduce the Monte-Carlo running time and obtain converged results within reasonable time limit. The coupled

  2. Dynamics of coupled electron-nuclei-systems in laser fields

    International Nuclear Information System (INIS)

    Falge, Mirjam

    2012-01-01

    This work aimed at the theoretical analysis of high harmonic generation in molecules and the influence of coupled electron and nuclear dynamics on ultra-short pulse ionization processes. In the first part of this thesis, the isotope effect and influence of vibrational excitation on high harmonic generation were investigated for the isotope pairs H 2 O/D 2 O and H 2 /D 2 . It was shown that on the one hand high harmonic intensities strongly depend on the vibrational quantum number of the initial state of the water molecule and on the other hand the spectra of H 2 O and D 2 O exhibit a clear isotope effect for certain vibrationally excited states. Also it was shown that high harmonics of vibrationally excited states show an even more pronounced isotope effect than the ground state. The second and third part of this work treats the influence of coupled electron and nuclear dynamics on photoelectron spectra. In order to facilitate a numerically exact description of this dynamics, a simple one-dimensional model system (Shin-Metiu model) was used. It consists of only a single electronic and nuclear degree-of-freedom and allows for a switching between adiabatic and strongly non-adiabatic dynamics by its parameterization. This model served for the analysis of the dynamics of three different cases ranging from weak over intermediate to strong electron-nuclear coupling. To investigate the influence of non-adiabatic effects on photoelectron spectra, time-resolved photoelectron spectra were calculated applying two methods: a numerically exact treatment and an adiabatic approach neglecting the electron-nuclear coupling. Subsequently, the dependence of the efficiency of a non-adiabatic transition on the nuclear mass was analysed. To this end, the population dynamics and photoelectron spectra were calculated numerically exactly for a strong electron and nuclear coupling. Thereafter the asymmetry in forward and backward direction of time-resolved photoelectron spectra and the

  3. Optimization design of high power ultrasonic circular ring radiator in coupled vibration.

    Science.gov (United States)

    Xu, Long; Lin, Shuyu; Hu, Wenxu

    2011-10-01

    This paper presents a new high power ultrasonic (HPU) radiator, which consists of a transducer, an ultrasonic horn, and a metal circular ring. Both the transducer and horn in longitudinal vibrations are used to drive a metal circular ring in a radial-axial coupled vibration. This coupled vibration cannot only generate ultrasound in both the radial and axial directions, but also focus the ultrasound inside the circular ring. Except for the radial-axial coupled vibration mode, the third longitudinal harmonic vibration mode with relative large vibration amplitude is also detected, which can be used as another operation mode. Overall, the HPU with these two vibration modes should have good potential to be applied in liquid processing, such as sonochemistry, ultrasonic cleaning, and Chinese herbal medicine extraction. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. 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.)

  5. Deflecting modes of the side-coupled cavity structure

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, Shigemi.

    1990-11-01

    The deflecting modes of the 805 MHz side-coupled cavity structure with the relativistic factor 0.566 are studied. Our main concern is the dispersion properties among different configurations of side-coupling cells and their interpretations. It is shown that the ninety degree side-coupling cell configuration, so to speak, the Mickey Mouse configuration has a merit in reducing the HEM{sub 1} passband. Another concern is the magnitude of the transverse coupling impedance around the synchronization condition. It is shown that the existence of the coupling cell introduces the nonuniformity of the deflecting mode and gives different impedance relative to the beam axis and that the coupling impedance at {pi}/10 exceeds 50 M{Omega}/m if the quality value of the mode is around 12000.

  6. Deflecting modes of the side-coupled cavity structure

    International Nuclear Information System (INIS)

    Inagaki, Shigemi.

    1990-11-01

    The deflecting modes of the 805 MHz side-coupled cavity structure with the relativistic factor 0.566 are studied. Our main concern is the dispersion properties among different configurations of side-coupling cells and their interpretations. It is shown that the ninety degree side-coupling cell configuration, so to speak, the Mickey Mouse configuration has a merit in reducing the HEM 1 passband. Another concern is the magnitude of the transverse coupling impedance around the synchronization condition. It is shown that the existence of the coupling cell introduces the nonuniformity of the deflecting mode and gives different impedance relative to the beam axis and that the coupling impedance at π/10 exceeds 50 MΩ/m if the quality value of the mode is around 12000

  7. Impact of floating mass transducer coupling and positioning in round window vibroplasty.

    Science.gov (United States)

    Rajan, Gunesh P; Lampacher, Peter; Ambett, Ranjeeta; Dittrich, Gregor; Kuthubutheen, Jafri; Wood, Bradley; McArthur, Anne; Marino, Roberta

    2011-02-01

    The round window application of the Vibrant Sound bridge, the so-called round window vibroplasty, is gaining increasing popularity for hearing rehabilitation of patients with mixed hearing loss or conductive hearing loss. In these patients, conventional hearing amplification and/or surgical restoration is either not possible or has failed because of chronic ear disease, extensive otosclerosis, or malformations. The exact mechanisms of direct cochlear stimulation via the round window membrane are not yet completely understood. It is unclear what kind and what degree of contact is required between the floating mass transducer (FMT) and the round window membrane (RWM) to elicit a functional hearing perception with the implant. We investigated the coupling efficiency between the FMT and the RWM and how the efficiency is altered by the FMT position, the degree of FMT-RWM contact, and the use of a soft tissue coupler. Prospective cohort study. Tertiary referral center in Western Australia. Patients undergoing round window vibroplasty for a mixed or conductive hearing loss otherwise not aidable. Patients underwent round window vibroplasty and received audiological and coupling analysis in the follow-up. These data were then correlated with FMT positioning and the extent of FMT-RWM interface as determined by postoperative high-resolution temporal bone computed tomography. Coupling and hearing levels in relation to FMT positioning and degree of FMT-RWM contact. Of 10 patients, 8 were available for vibroplasty behavioral threshold testing. In 2 patients, testing could not be done because of wound breakdown requiring device explantation in 1 case, and in the other case, the bone conduction thresholds dropped 2 months after implantation, thus falling out of the performance range of the device. Postoperative FMT migration occurred in 50% of the patients (3/6) with recurrent chronic ear disease and status after multiple previous ear operations. All patients, including the 3

  8. Response and Uniformity Studies of Directly Coupled Tiles

    International Nuclear Information System (INIS)

    Zutshi, Vishnu

    2010-01-01

    A finely-segmented scintillator-based calorimeter which capitalizes on the marriage of proven detection techniques with novel solid-state photo-detector devices such as Multi-pixel Photon Counters (MPPCs) is an interesting calorimetric system from the point of view of future detector design. A calorimeter system consisting of millions of channels will require a high degree of integration. The first steps towards this integration have already been facilitated by the small size and magnetic field immunity of the MPPCs. The photo-conversion occurs right at the tile, thus obviating the need for routing of long clear fibers. Similar considerations apply to the presence of wave-length shifting (WLS) fibers inside the tiles which couple it to the photo-detectors. Significant simplification in construction and assembly ensue if the MPPCs can be coupled directly to the scintillator tiles. Equally importantly, the total absence of fibers would offer greater flexibility in the choice of the transverse segmentation while enhancing the electro-mechanical integrability of the design. The NIU high-energy physics group has been studying the fiberless or direct-coupling option for some time now. Encouraging results on response and response uniformity have been obtained using radioactive sources. This MOU seeks to set up a framework to extend these tests using beams at the MTBF. The results will be relevant to high granularity scintillator/crystal electromagnetic and hadronic calorimetry. The tests involve a set of small directly-coupled tile counters fabricated at NIU which will be placed in the beam to study their response and response uniformity as a function of the incident position of the particles passing through them.

  9. Response and Uniformity Studies of Directly Coupled Tiles

    Energy Technology Data Exchange (ETDEWEB)

    Zutshi, Vishnu

    2010-04-02

    A finely-segmented scintillator-based calorimeter which capitalizes on the marriage of proven detection techniques with novel solid-state photo-detector devices such as Multi-pixel Photon Counters (MPPCs) is an interesting calorimetric system from the point of view of future detector design. A calorimeter system consisting of millions of channels will require a high degree of integration. The first steps towards this integration have already been facilitated by the small size and magnetic field immunity of the MPPCs. The photo-conversion occurs right at the tile, thus obviating the need for routing of long clear fibers. Similar considerations apply to the presence of wave-length shifting (WLS) fibers inside the tiles which couple it to the photo-detectors. Significant simplification in construction and assembly ensue if the MPPCs can be coupled directly to the scintillator tiles. Equally importantly, the total absence of fibers would offer greater flexibility in the choice of the transverse segmentation while enhancing the electro-mechanical integrability of the design. The NIU high-energy physics group has been studying the fiberless or direct-coupling option for some time now. Encouraging results on response and response uniformity have been obtained using radioactive sources. This MOU seeks to set up a framework to extend these tests using beams at the MTBF. The results will be relevant to high granularity scintillator/crystal electromagnetic and hadronic calorimetry. The tests involve a set of small directly-coupled tile counters fabricated at NIU which will be placed in the beam to study their response and response uniformity as a function of the incident position of the particles passing through them.

  10. High-Efficiency High Step-Up DC-DC Converter with Dual Coupled Inductors for Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Forouzesh, Mojtaba; Shen, Yanfeng; Siwakoti, Yam Prasad

    2018-01-01

    with a common ground connection of the input and output make the proposed topology a proper candidate for a transformer-less grid connected photovoltaic systems. The operating performance, analysis and mathematical derivations of the proposed dc-dc converter have been demonstrated in the paper. Moreover......This paper introduces a non-isolated high step-up dc-dc converter with dual coupled inductors suitable for distributed generation applications. By implementing an input parallel connection, the proposed dc-dc structure inherits shared input current with low ripple, which also requires small...... capacitive filter at its input. Moreover, this topology can reach high voltage gain by using dual coupled inductors in series connection at the output stage. The proposed converter uses active clamp circuits with a shared clamp capacitor for the main switches. In addition to the active clamp circuit...

  11. Discrete and continuous joint coupling relationships in uninjured recreational runners.

    Science.gov (United States)

    Dierks, Tracy A; Davis, Irene

    2007-06-01

    Abnormal joint coupling is thought to be related to overuse injuries in runners. However, researchers do not yet know what constitutes normal joint coupling during running, which makes abnormal coupling difficult to define. Lower extremity kinematics were collected from 40 recreational runners during stance. Joint coupling methods were applied and, for each method, means and both within- and between-subject variability were calculated. The 95% confidence interval was used to compare differences across coupling relationships and periods of stance. Timing between rearfoot eversion, tibial internal rotation, and knee flexion were relatively synchronous while relationships involving knee internal rotation were more asynchronous. The excursion ratios showed that every 2 degrees of rearfoot eversion was coupled with 1 degrees of both tibial internal rotation and knee internal rotation. Vector coding results showed that just beyond maximum loading, all joint coupling relationships resulted in relatively equal amounts of motion, while the within-subject variability was similar throughout stance. The continuous relative phase results showed that the most out-of-phase coupling occurred in the periods around heel-strike and toe-off while the most in-phase coupling occurred in the period just beyond maximum loading of the leg. The continuous relative phase within-subject variability was greatest at the periods around heel-strike and toe-off and smallest just beyond maximum loading. With a better understanding of joint coupling in uninjured runners, these data will help to serve as a reference for future studies investigating the relationship between running injuries and abnormal joint coupling.

  12. On the Nonlinear Structural Analysis of Wind Turbine Blades using Reduced Degree-of-Freedom Models

    DEFF Research Database (Denmark)

    Holm-Jørgensen, Kristian; Larsen, Jesper Winther; Nielsen, Søren R.K.

    2008-01-01

    , modelling geometrical and inertial nonlinear couplings in the fundamental flap and edge direction. The purpose of this article is to examine the applicability of such a reduced-degree-of-freedom model in predicting the nonlinear response and stability of a blade by comparison to a full model based...... on a nonlinear co-rotating FE formulation. By use of the reduced-degree-of-freedom model it is shown that under strong resonance excitation of the fundamental flap or edge modes, significant energy is transferred to higher modes due to parametric or nonlinear coupling terms, which influence the response...... of the small number of included modes. The qualitative erratic response and stability prediction of the reduced order models take place at frequencies slightly above normal operation. However, for normal operation of the wind turbine without resonance excitation 4 modes in the reduced-degree-of-freedom model...

  13. The Role of Strong Coupling in Z-Pinch-Driven Approaches to High Yield Inertial Confinement Fusion

    International Nuclear Information System (INIS)

    MEHLHORN, THOMAS A.; DESJARLAIS, MICHAEL P.; HAILL, THOMAS A.; LASH, JOEL S.; ROSENTHAL, STEPHEN E.; SLUTZ, STEPHEN A.; STOLTZ, PETER H.; VESEY, ROGER A.; OLIVER, B.

    1999-01-01

    Peak x-ray powers as high as 280 ± 40 TW have been generated from the implosion of tungsten wire arrays on the Z Accelerator at Sandia National Laboratories. The high x-ray powers radiated by these z-pinches provide an attractive new driver option for high yield inertial confinement fusion (ICF). The high x-ray powers appear to be a result of using a large number of wires in the array which decreases the perturbation seed to the magnetic Rayleigh-Taylor (MRT) instability and diminishes other 3-D effects. Simulations to confirm this hypothesis require a 3-D MHD code capability, and associated databases, to follow the evolution of the wires from cold solid through melt, vaporization, ionization, and finally to dense imploded plasma. Strong coupling plays a role in this process, the importance of which depends on the wire material and the current time history of the pulsed power driver. Strong coupling regimes are involved in the plasmas in the convolute and transmission line of the powerflow system. Strong coupling can also play a role in the physics of the z-pinch-driven high yield ICF target. Finally, strong coupling can occur in certain z-pinch-driven application experiments

  14. Strong exciton-photon coupling in organic single crystal microcavity with high molecular orientation

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Kaname [Department of Electronics, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Yamashita, Kenichi, E-mail: yamasita@kit.ac.jp [Faculty of Electrical Engineering and Electronics, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Yanagi, Hisao [Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan); Yamao, Takeshi; Hotta, Shu [Faculty of Materials Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan)

    2016-08-08

    Strong exciton-photon coupling has been observed in a highly oriented organic single crystal microcavity. This microcavity consists of a thiophene/phenylene co-oligomer (TPCO) single crystal laminated on a high-reflection distributed Bragg reflector. In the TPCO crystal, molecular transition dipole was strongly polarized along a certain horizontal directions with respect to the main crystal plane. This dipole polarization causes significantly large anisotropies in the exciton transition and optical constants. Especially the anisotropic exciton transition was found to provide the strong enhancement in the coupling with the cavity mode, which was demonstrated by a Rabi splitting energy as large as ∼100 meV even in the “half-vertical cavity surface emitting lasing” microcavity structure.

  15. Strong exciton-photon coupling in organic single crystal microcavity with high molecular orientation

    Science.gov (United States)

    Goto, Kaname; Yamashita, Kenichi; Yanagi, Hisao; Yamao, Takeshi; Hotta, Shu

    2016-08-01

    Strong exciton-photon coupling has been observed in a highly oriented organic single crystal microcavity. This microcavity consists of a thiophene/phenylene co-oligomer (TPCO) single crystal laminated on a high-reflection distributed Bragg reflector. In the TPCO crystal, molecular transition dipole was strongly polarized along a certain horizontal directions with respect to the main crystal plane. This dipole polarization causes significantly large anisotropies in the exciton transition and optical constants. Especially the anisotropic exciton transition was found to provide the strong enhancement in the coupling with the cavity mode, which was demonstrated by a Rabi splitting energy as large as ˜100 meV even in the "half-vertical cavity surface emitting lasing" microcavity structure.

  16. Strong exciton-photon coupling in organic single crystal microcavity with high molecular orientation

    International Nuclear Information System (INIS)

    Goto, Kaname; Yamashita, Kenichi; Yanagi, Hisao; Yamao, Takeshi; Hotta, Shu

    2016-01-01

    Strong exciton-photon coupling has been observed in a highly oriented organic single crystal microcavity. This microcavity consists of a thiophene/phenylene co-oligomer (TPCO) single crystal laminated on a high-reflection distributed Bragg reflector. In the TPCO crystal, molecular transition dipole was strongly polarized along a certain horizontal directions with respect to the main crystal plane. This dipole polarization causes significantly large anisotropies in the exciton transition and optical constants. Especially the anisotropic exciton transition was found to provide the strong enhancement in the coupling with the cavity mode, which was demonstrated by a Rabi splitting energy as large as ∼100 meV even in the “half-vertical cavity surface emitting lasing” microcavity structure.

  17. Some results on the neutron transport and the coupling of equations

    International Nuclear Information System (INIS)

    Bal, G.

    1997-01-01

    Neutron transport in nuclear reactors is well modeled by the linear Boltzmann transport equation. Its resolution is relatively easy but very expensive. To achieve whole core calculations, one has to consider simpler models, such as diffusion or homogeneous transport equations. However, the solutions may become inaccurate in particular situations (as accidents for instance). That is the reason why we wish to solve the equations on small area accurately and more coarsely on the remaining part of the core. It is than necessary to introduce some links between different discretizations or modelizations. In this note, we give some results on the coupling of different discretizations of all degrees of freedom of the integral-differential neutron transport equation (two degrees for the angular variable, on for the energy component, and two or three degrees for spatial position respectively in 2D (cylindrical symmetry) and 3D). Two chapters are devoted to the coupling of discrete ordinates methods (for angular discretization). The first one is theoretical and shows the well posing of the coupled problem, whereas the second one deals with numerical applications of practical interest (the results have been obtained from the neutron transport code developed at the R and D, which has been modified for introducing the coupling). Next, we present the nodal scheme RTN0, used for the spatial discretization. We show well posing results for the non-coupled and the coupled problems. At the end, we deal with the coupling of energy discretizations for the multigroup equations obtained by homogenization. Some theoretical results of the discretization of the velocity variable (well-posing of problems), which do not deal directly with the purposes of coupling, are presented in the annexes. (author)

  18. Geometric variations in high index-contrast waveguides, coupled mode theory in curvilinear coordinates.

    Science.gov (United States)

    Skorobogatiy, Maksim; Jacobs, Steven; Johnson, Steven; Fink, Yoel

    2002-10-21

    Perturbation theory formulation of Maxwell's equations gives a theoretically elegant and computationally efficient way of describing small imperfections and weak interactions in electro-magnetic systems. It is generally appreciated that due to the discontinuous field boundary conditions in the systems employing high dielectric contrast profiles standard perturbation formulations fail when applied to the problem of shifted material boundaries. In this paper we developed a novel coupled mode and perturbation theory formulations for treating generic non-uniform (varying along the direction of propagation) perturbations of a waveguide cross-section based on Hamiltonian formulation of Maxwell equations in curvilinear coordinates. We show that our formulation is accurate and rapidly converges to an exact result when used in a coupled mode theory framework even for the high index-contrast discontinuous dielectric profiles. Among others, our formulation allows for an efficient numerical evaluation of induced PMD due to a generic distortion of a waveguide profile, analysis of mode filters, mode converters and other optical elements such as strong Bragg gratings, tapers, bends etc., and arbitrary combinations of thereof. To our knowledge, this is the first time perturbation and coupled mode theories are developed to deal with arbitrary non-uniform profile variations in high index-contrast waveguides.

  19. Semiclassical description of scattering with internal degrees of freedom

    International Nuclear Information System (INIS)

    Cruz-Barrios, S.; Gomez-Camacho, J.

    1998-01-01

    The scattering of systems with internal degrees of freedom is studied in the semi-classical approximation. It is found that a special set of states, named coherent internal states, are specially relevant for the semi-classical treatment. A classical trajectory is defined for each coherent internal state. The semi-classical expressions obtained satisfy the superposition principle and are valid for arbitrary coupling strength. (orig.)

  20. Macroscopic Magnetic Coupling Effect: The Physical Origination of a High-Temperature Superconducting Flux Pump

    Science.gov (United States)

    Wang, Wei; Coombs, Tim

    2018-04-01

    We have uncovered at the macroscopic scale a magnetic coupling phenomenon in a superconducting YBa2Cu3O7 -δ (YBCO) film, which physically explains the mechanism of the high-temperature superconducting flux pump. The coupling occurs between the applied magnetic poles and clusters of vortices induced in the YBCO film, with each cluster containing millions of vortices. The coupling energy is verified to originate from the inhomogeneous field of the magnetic poles, which reshapes the vortex distribution, aggregates millions of vortices into a single cluster, and accordingly moves with the poles. A contrast study is designed to verify that, to provide the effective coupling energy, the applied wavelength must be short while the field amplitude must be strong, i.e., local-field inhomogeneity is the crucial factor. This finding broadens our understanding of the collective vortex behavior in an applied magnetic field with strong local inhomogeneity. Moreover, this phenomenon largely increases the controlled vortex flow rate by several orders of magnitude compared with existing methods, providing motivation for and physical support to a new branch of wireless superconducting dc power sources, i.e., the high-temperature superconducting flux pump.

  1. Theory of magnetoelectric coupling in 2-2-type magnetostrictive/piezoelectric composite film with texture

    International Nuclear Information System (INIS)

    Liu Chaoqian; Fei Weidong; Li Weili

    2008-01-01

    It is well accepted that textures in polycrystalline films have significant effects on film properties. The magnetoelectric (ME) coupling in a 2-2-type multiferroic composite film was theoretically discussed using Landau-Ginsburg-Devonshire theory, where the influences of dispersive texture and residual stress were considered. As an example, the 2-2-type CoFe 2 O 4 /BaTiO 3 composite film was theoretically analysed, wherein the case of both the magnetostrictive phase and the piezoelectric phase with (0 0 1)-oriented texture was considered. Our results show that the ME coupling is enhanced with the texture degree of the piezoelectric phase and/or the magnitude of the residual tensile stress, but weakened with the magnitude of residual compressive stress. With increasing texture degree of the magnetostrictive phase, the ME coupling is enhanced when the texture degree is smaller than a critical value, but weakened when the texture degree is larger than the critical value

  2. The LTAN solution for radiative transfer problems without azimuthal symmetry and high degree of anisotropy

    International Nuclear Information System (INIS)

    Cardona, Augusto V.; Vilhena, Marco T. de; Segatto, Cynthia F.

    2005-01-01

    In this work we solve the radiative transfer problem without azimuthal symmetry with high degree of anisotropy using the LTAN method and the Laplace inverse transformation by the diagonalization of the large symbolic LTAN matrix. We report numerical simulations and comparisons with available results of the literature. (author)

  3. High-flux cold rubidium atomic beam for strongly-coupled cavity QED

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Basudev [Indian Institute of Science Education and Research, Kolkata (India); University of Maryland, MD (United States); Scholten, Michael [University of Maryland, MD (United States)

    2012-08-15

    This paper presents a setup capable of producing a high-flux continuous beam of cold rubidium atoms for cavity quantum electrodynamics experiments in the region of strong coupling. A 2D{sup +} magneto-optical trap (MOT), loaded with rubidium getters in a dry-film-coated vapor cell, fed a secondary moving-molasses MOT (MM-MOT) at a rate greater than 2 x 10{sup 10} atoms/s. The MM-MOT provided a continuous beam with a tunable velocity. This beam was then directed through the waist of a cavity with a length of 280 μm, resulting in a vacuum Rabi splitting of more than ±10 MHz. The presence of a sufficient number of atoms in the cavity mode also enabled splitting in the polarization perpendicular to the input. The cavity was in the strong coupling region, with an atom-photon dipole coupling coefficient g of 7 MHz, a cavity mode decay rate κ of 3 MHz, and a spontaneous emission decay rate γ of 6 MHz.

  4. poincare surface analysis of two coupled quintic oscillators in a ...

    African Journals Online (AJOL)

    DJFLEX

    We have investigated the chaotic dynamics of two coupled quintic oscillators in a single well potential as the energy of the oscillator increases, keeping the coupling strength constant. The degree of chaoticity does not increase monotonously with the energy as regular regions reappear within chaotic seas as the energy ...

  5. Poincare surface analysis of two coupled quintic oscillators in a ...

    African Journals Online (AJOL)

    We have investigated the chaotic dynamics of two coupled quintic oscillators in a single well potential as the energy of the oscillator increases, keeping the coupling strength constant. The degree of chaoticity does not increase monotonously with the energy as regular regions reappear within chaotic seas as the energy ...

  6. Strong Coupling and Entanglement of Quantum Emitters Embedded in a Nanoantenna-Enhanced Plasmonic Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Hensen, Matthias [Institut; Heilpern, Tal [Center; Gray, Stephen K. [Center; Pfeiffer, Walter [Fakultät

    2017-10-12

    Establishing strong coupling between spatially separated and thus selectively addressable quantum emitters is a key ingredient to complex quantum optical schemes in future technologies. Insofar as many plasmonic nanostructures are concerned, however, the energy transfer and mutual interaction strength between distant quantum emitters can fail to provide strong coupling. Here, based on mode hybridization, the longevity and waveguide character of an elliptical plasmon cavity are combined with intense and highly localized field modes of suitably designed nanoantennas. Based on FDTD simulations a quantum emitter-plasmon coupling strength hg = 16.7 meV is reached while simultaneously keeping a small plasmon resonance line width h gamma(s) = 33 meV. This facilitates strong coupling, and quantum dynamical simulations reveal an oscillatory exchange of excited state population arid a notable degree of entanglement between the quantum emitters spatially separated by 1.8 mu m, i.e., about twice the operating wavelength.

  7. Proof-of-principle of high-fidelity coupled CRUD deposition and cycle depletion simulation

    International Nuclear Information System (INIS)

    Walter, Daniel J.; Kendrick, Brian K.; Petrov, Victor; Manera, Annalisa; Collins, Benjamin; Downar, Thomas

    2015-01-01

    A multiphysics framework for the high-fidelity simulation of CRUD deposition is developed to better understand the coupled physics and their respective feedback mechanisms. This framework includes the primary physics of lattice depletion, computational fluid dynamics, and CRUD chemistry. The three physics are coupled together via the operator-splitting technique, where predictor–corrector and fixed-point iteration schemes are utilized to converge the nonlinear solution. High-fidelity simulations may provide a means to predict and assess potential operating issues, including CRUD induced power shift and CRUD induced localized corrosion, known as CIPS and CILC, respectively. As a proof-of-principle, a coupled 500-day cycle depletion simulation of a pressurized water reactor fuel pin cell was performed using the coupled code suite; a burnup of 31 MWd/kgHM was reached. The simulation recreated the classic striped CRUD pattern often seen on pulled fuel rods containing CRUD. It is concluded that the striping is caused by the flow swirl induced by spacer grid mixing vanes. Two anti-correlated effects contribute to the striping: (1) the flow swirl yields significant azimuthal temperature variations, which impact the locations where CRUD deposits, and (2) the flow swirl is correlated to increased shear stress along the cladding surface and subsequent erosion of the CRUD layer. The CIPS condition of the core is concluded to be primarily controlled by lithium tetraborate precipitation, referred to as boron hideout, which occurs in regions experiencing subcooled nucleate boiling as soluble boron and lithium species reach their solubility limit within the CRUD layer. Subsequently, a localized reduction in power occurs due to the high neutron absorption cross section of boron-10

  8. High-degree Gravity Models from GRAIL Primary Mission Data

    Science.gov (United States)

    Lemoine, Frank G.; Goossens, Sander J.; Sabaka, Terence J.; Nicholas, Joseph B.; Mazarico, Erwan; Rowlands, David D.; Loomis, Bryant D.; Chinn, Douglas S.; Caprette, Douglas S.; Neumann, Gregory A.; hide

    2013-01-01

    We have analyzed Ka?band range rate (KBRR) and Deep Space Network (DSN) data from the Gravity Recovery and Interior Laboratory (GRAIL) primary mission (1 March to 29 May 2012) to derive gravity models of the Moon to degree 420, 540, and 660 in spherical harmonics. For these models, GRGM420A, GRGM540A, and GRGM660PRIM, a Kaula constraint was applied only beyond degree 330. Variance?component estimation (VCE) was used to adjust the a priori weights and obtain a calibrated error covariance. The global root?mean?square error in the gravity anomalies computed from the error covariance to 320×320 is 0.77 mGal, compared to 29.0 mGal with the pre?GRAIL model derived with the SELENE mission data, SGM150J, only to 140×140. The global correlations with the Lunar Orbiter Laser Altimeter?derived topography are larger than 0.985 between l = 120 and 330. The free?air gravity anomalies, especially over the lunar farside, display a dramatic increase in detail compared to the pre?GRAIL models (SGM150J and LP150Q) and, through degree 320, are free of the orbit?track?related artifacts present in the earlier models. For GRAIL, we obtain an a posteriori fit to the S?band DSN data of 0.13 mm/s. The a posteriori fits to the KBRR data range from 0.08 to 1.5 micrometers/s for GRGM420A and from 0.03 to 0.06 micrometers/s for GRGM660PRIM. Using the GRAIL data, we obtain solutions for the degree 2 Love numbers, k20=0.024615+/-0.0000914, k21=0.023915+/-0.0000132, and k22=0.024852+/-0.0000167, and a preliminary solution for the k30 Love number of k30=0.00734+/-0.0015, where the Love number error sigmas are those obtained with VCE.

  9. Eocene greenhouse climate revealed by coupled clumped isotope-Mg/Ca thermometry.

    Science.gov (United States)

    Evans, David; Sagoo, Navjit; Renema, Willem; Cotton, Laura J; Müller, Wolfgang; Todd, Jonathan A; Saraswati, Pratul Kumar; Stassen, Peter; Ziegler, Martin; Pearson, Paul N; Valdes, Paul J; Affek, Hagit P

    2018-02-06

    Past greenhouse periods with elevated atmospheric CO 2 were characterized by globally warmer sea-surface temperatures (SST). However, the extent to which the high latitudes warmed to a greater degree than the tropics (polar amplification) remains poorly constrained, in particular because there are only a few temperature reconstructions from the tropics. Consequently, the relationship between increased CO 2 , the degree of tropical warming, and the resulting latitudinal SST gradient is not well known. Here, we present coupled clumped isotope (Δ 47 )-Mg/Ca measurements of foraminifera from a set of globally distributed sites in the tropics and midlatitudes. Δ 47 is insensitive to seawater chemistry and therefore provides a robust constraint on tropical SST. Crucially, coupling these data with Mg/Ca measurements allows the precise reconstruction of Mg/Ca sw throughout the Eocene, enabling the reinterpretation of all planktonic foraminifera Mg/Ca data. The combined dataset constrains the range in Eocene tropical SST to 30-36 °C (from sites in all basins). We compare these accurate tropical SST to deep-ocean temperatures, serving as a minimum constraint on high-latitude SST. This results in a robust conservative reconstruction of the early Eocene latitudinal gradient, which was reduced by at least 32 ± 10% compared with present day, demonstrating greater polar amplification than captured by most climate models.

  10. Gate-dependent spin-orbit coupling in multielectron carbon nanotubes

    DEFF Research Database (Denmark)

    Jespersen, Thomas Sand; Grove-Rasmussen, Kasper; Paaske, Jens

    2011-01-01

    Understanding how the orbital motion of electrons is coupled to the spin degree of freedom in nanoscale systems is central for applications in spin-based electronics and quantum computation. Here we demonstrate such spin–orbit coupling in a carbon-nanotube quantum dot in the general multielectron...... graphene lattice. Our findings suggest that the spin–orbit coupling is a general property of carbon-nanotube quantum dots, which should provide a unique platform for the study of spin–orbit effects and their applications....

  11. Estimate of electrical potential difference between plasmas with different degrees of ionization

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-12

    The electrical potential difference has been estimated across the mixing region of two plasmas with different degrees of ionization. The estimation has been carried out in two different contexts of a charge neutral mixing region and a charge non-neutral sheath. Ion energy gained due to the potential difference has also been estimated. In both analyses, ion energy gain is proportional to the degree of ionization, and a fairly large ionization appears to be needed for overcoming the potential energy barrier of strongly coupled plasmas.

  12. Fracture toughness testing of V-4Cr-4Ti at 25{degrees}C and -196{degrees}C

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.X.; Kurtz, R.J. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-10-01

    Measurements of the fracture toughness of the production-scale heat (832665) of V-4Cr-4Ti have been performed at 25{degrees}C and {minus}196{degrees}C using compact tension (CT) specimens. Test specimens were vacuum annealed at either 1000{degrees}C for 1 hour (HT1) or 1050{degrees}C for two hours (HT2). Specimens given the HT1 treatment were annealed after final machining, whereas the HT2 specimens received the 1050{degrees}C anneal at Teledyne Wah Chang prior to final machining. Following machining HT2 specimens were then vacuum annealed at 180{degrees}C for two hours to remove hydrogen. Specimens treated using HT1 had a partially recrystallized microstructure and those treated using HT2 had a fully recrystallized microstructure. The fracture toughness at 25{degrees}C was determined by J-integral tests and at {minus}196{degrees}C by ASTM E 399 type tests. Toughness values obtained at {minus}196{degrees}C were converted to J-integral values for comparison to the 25{degrees}C data. The 25{degrees}C fracture toughness was very high with none of the specimens giving valid results per ASTM criteria. Specimens fractured by microvoid coalescence. The fracture toughness at {minus}196{degrees}C was much lower than that at 25{degrees}C and the fracture surface showed predominantly cleavage features. The present results show a transition from ductile to brittle behavior with decreasing test temperature which is not observed from one-third scale Charpy impact tests. The fracture toughness at {minus}196{degrees}C was still quite high, however, at about 75 kJ/m{sup 2}. Delaminations in planes normal to the thickness direction were seen at both test temperatures. Fracture surfaces inside the delaminations exhibited nearly 100% cleavage facets. The cause of the brittle delaminations was not determined, but will be a subject for further investigation.

  13. Coupled-Multiplier Accelerator Produces High-Power Electron Beams for Industrial Applications

    International Nuclear Information System (INIS)

    Hatridge, M.; McIntyre, P.; Roberson, S.; Sattarov, A.; Thomas, E.; Meitzler, Charles

    2003-01-01

    The coupled multiplier is a new approach to efficient generation of MeV d.c. power for accelerator applications. High voltage is produced by a series of modules, each of which consists of a high-power alternator, step-up transformer, and 3-phase multiplier circuit. The alternators are connected mechanically along a rotating shaft, and connected by insulating flexible couplers. This approach differs from all previous d.c. technologies in that power is delivered to the various stages of the system mechanically, rather than through capacitive or inductive electrical coupling. For this reason the capital cost depends linearly on required voltage and power, rather than quadratically as with conventional technologies. The CM technology enables multiple electron beams to be driven within a common supply and insulating housing. MeV electron beam is extremely effective in decomposing organic contaminants in water. A 1 MeV, 100 kW industrial accelerator using the CM technology has been built and is being installed for treatment of wastewater at a petrochemical plant

  14. Effect of coupling behavior on groundwater flow for geological disposal of radioactive high level waste

    International Nuclear Information System (INIS)

    Kurikami, Hiroshi; Kobayashi, Akira; Ohnishi, Yuzo; Chijimatsu, Masakazu

    2003-01-01

    In order to estimate the effects of coupled thermal-hydraulic-mechanical phenomena in near-field for geological disposal of high-level radioactive waste on a vast groundwater flow system, a far-field analysis was simulated based on the results of the simulation of coupled phenomena in near-field using averaged tensor and heat flux. From the results of the coupled analyses of near-field and far-field it was clarified that groundwater flow system was influenced by coupled phenomena in near-field. Moreover, it can be said that groundwater flux into a disposal tunnel is regarded as a complement to safety assessment of a disposal because it strongly correlates with traveling time of groundwater. (author)

  15. 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.

  16. Numerical study of droplet evaporation in coupled high-temperature and electrostatic fields

    Directory of Open Access Journals (Sweden)

    Ziwen Zuo

    2015-03-01

    Full Text Available The evaporation of a sessile water droplet under the coupled electrostatic and high-temperature fields is studied numerically. The leaky dielectric model and boiling point evaporation model are used for calculating the electric force and heat mass transfer. The free surface is captured using the volume of fluid method accounting for the variable surface tension and the transition of physical properties across the interface. The flow behaviors and temperature evolutions in different applied fields are predicted. It shows that in the coupled fields, the external electrostatic field restrains the flow inside the droplet and keeps a steady circulation. The flow velocity is reduced due to the interaction between electric body force and the force caused by temperature gradient. The heat transfer from air into the droplet is reduced by the lower flow velocity. The evaporation rate of the droplet in the high-temperature field is decreased.

  17. Coupling single NV-centres to high-Q whispering gallery modes of a preselected frequency-matched microresonator

    International Nuclear Information System (INIS)

    Schietinger, Stefan; Benson, Oliver

    2009-01-01

    In this paper, we report the controlled coupling of fluorescence from a single NV-centre in a single nanodiamond to the high-Q modes of a preselected microsphere. Microspheres from an ensemble with a finite size distribution can be characterized precisely via white light Mie-scattering. The mode spectrum of individual spheres can be determined with high precision. A sphere with an appropriate spectrum can be selected, and a nanodiamond containing a single NV-centre can be coupled to it. The spectral position of the calculated lowest order whispering gallery modes are found to be in very good agreement with the experimentally observed resonances of the coupled fluorescence from the single NV-re.

  18. Cross-Regional Assessment Of Coupling And Variability In Precipitation-Runoff Relationships

    Science.gov (United States)

    Carey, S. K.; Tetzlaff, D.; Soulsby, C.; Buttle, J. M.; Laudon, H.; McDonnell, J. J.; McGuire, K. J.; Seibert, J.; Shanley, J. B.

    2011-12-01

    The higher mid-latitudes of the northern hemisphere are particularly sensitive to change due to the important role the zero-degree isotherm plays in the phase of precipitation and intermediate storage as snow. An international inter-catchment comparison program North-Watch seeks to improve our understanding of the sensitivity of northern catchments to change by examining their hydrological and biogeochemical variability and response. The catchments are located in Sweden (Krycklan), Scotland (Mharcaidh, Girnock and Strontian), the United States (Sleepers River, Hubbard Brook and HJ Andrews) and Canada (Catamaran, Dorset and Wolf Creek). For this study, 8 catchments with 10 continuous years of daily precipitation and runoff data were selected to assess the seasonal coupling of rainfall and runoff and the memory effect of runoff events on the hydrograph at different time scales. To assess the coupling and synchroneity of precipitation, continuous wavelet transforms and wavelet coherence were used. Wavelet spectra identified the relative importance of both annual versus seasonal flows while wavelet coherence was applied to identify over different time scales along the 10-year window how well precipitation and runoff were coupled. For example, while on a given day, precipitation may be closely coupled to runoff, a wet year may not necessarily be a high runoff year in catchments with large storage. Assessing different averaging periods in the variation of daily flows highlights the importance of seasonality in runoff response and the relative influence of rain versus snowmelt on flow magnitude and variability. Wet catchments with limited seasonal precipitation variability (Strontian, Girnock) have precipitation signals more closely coupled with runoff, whereas dryer catchments dominated by snow (Wolf Creek, Krycklan) have strongly coupling only during freshet. Most catchments with highly seasonal precipitation show strong intermittent coupling during their wet season. At

  19. Simulating High Flux Isotope Reactor Core Thermal-Hydraulics via Interdimensional Model Coupling

    Energy Technology Data Exchange (ETDEWEB)

    Travis, Adam R [ORNL

    2014-05-01

    A coupled interdimensional model is presented for the simulation of the thermal-hydraulic characteristics of the High Flux Isotope Reactor core at Oak Ridge National Laboratory. The model consists of two domains a solid involute fuel plate and the surrounding liquid coolant channel. The fuel plate is modeled explicitly in three-dimensions. The coolant channel is approximated as a twodimensional slice oriented perpendicular to the fuel plate s surface. The two dimensionally-inconsistent domains are linked to one another via interdimensional model coupling mechanisms. The coupled model is presented as a simplified alternative to a fully explicit, fully three-dimensional model. Involute geometries were constructed in SolidWorks. Derivations of the involute construction equations are presented. Geometries were then imported into COMSOL Multiphysics for simulation and modeling. Both models are described in detail so as to highlight their respective attributes in the 3D model, the pursuit of an accurate, reliable, and complete solution; in the coupled model, the intent to simplify the modeling domain as much as possible without affecting significant alterations to the solution. The coupled model was created with the goal of permitting larger portions of the reactor core to be modeled at once without a significant sacrifice to solution integrity. As such, particular care is given to validating incorporated model simplifications. To the greatest extent possible, the decrease in solution time as well as computational cost are quantified versus the effects such gains have on the solution quality. A variant of the coupled model which sufficiently balances these three solution characteristics is presented alongside the more comprehensive 3D model for comparison and validation.

  20. High-Tc SNS Junctions: A New Generation of Proximity-Coupled Josephson Devices

    Science.gov (United States)

    Kleinsasser, A. W.

    1997-01-01

    This paper reviews this evolution of proximity - coupled Josephson jucntion from the early investigations on low temperature superconductor-normal -superconductor junctions through the introduction of hybrid superconductor-semiconductor devices and the resulting interest in mesoscopic Josephson junctions, to the recent development of high temperature devices.

  1. A novel method for the determination of the degree of deacetylation of chitosan by coulometric titration.

    Science.gov (United States)

    Wang, Chao; Yuan, Fang; Pan, Jiabao; Jiao, Shining; Jin, Ling; Cai, Hongwei

    2014-09-01

    A novel method to determine the degree of deacetylation of chitosan is described. In this method, the coulometric titrant OH- is generated by the electrolysis of water. The OH- reacted with the residual hydrochloric acid in chitosan solution and the degree of deacetylation was obtained by Faraday's law. The optimized experimental parameters in this study were 1.0 mol/L KCl as supporting electrolyte, 15.00 mA as the intensity of constant current, composite glass electrode as indicating electrode couples, double platinum generated electrode-platinum wire auxiliary electrode as working electrode pairs, pH 3.80 as the titration end-point. The degree of deacetylation in the four samples, which varied from 70 to 95% were measured. The results were similar to those from 1H NMR and the standard deviations were lower than 0.5%. With merit of simplicity, convenience, quickness, high accuracy and precision, automatic detection of titration end-point and low-cost, the proposed method will be very useful in the industrial production. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Partial alignment and measurement of residual dipolar couplings of proteins under high hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yinan; Wand, A. Joshua, E-mail: wand@mail.med.upenn.edu [University of Pennsylvania, Department of Biochemistry and Biophysics, Johnson Research Foundation (United States)

    2013-08-15

    High-pressure NMR spectroscopy has emerged as a complementary approach for investigating various structural and thermodynamic properties of macromolecules. Noticeably absent from the array of experimental restraints that have been employed to characterize protein structures at high hydrostatic pressure is the residual dipolar coupling, which requires the partial alignment of the macromolecule of interest. Here we examine five alignment media that are commonly used at ambient pressure for this purpose. We find that the spontaneous alignment of Pf1 phage, d(GpG) and a C12E5/n-hexnanol mixture in a magnetic field is preserved under high hydrostatic pressure. However, DMPC/DHPC bicelles and collagen gel are found to be unsuitable. Evidence is presented to demonstrate that pressure-induced structural changes can be identified using the residual dipolar coupling.

  3. Degree-degree correlations in directed networks with heavy-tailed degrees

    NARCIS (Netherlands)

    van der Hoorn, W.L.F.; Litvak, Nelli

    2013-01-01

    In network theory, Pearson's correlation coefficients are most commonly used to measure the degree assortativity of a network. We investigate the behavior of these coefficients in the setting of directed networks with heavy-tailed degree sequences. We prove that for graphs where the in- and

  4. Using constitutive activity to define appropriate high-throughput screening assays for orphan g protein-coupled receptors.

    Science.gov (United States)

    Ngo, Tony; Coleman, James L J; Smith, Nicola J

    2015-01-01

    Orphan G protein-coupled receptors represent an underexploited resource for drug discovery but pose a considerable challenge for assay development because their cognate G protein signaling pathways are often unknown. In this methodological chapter, we describe the use of constitutive activity, that is, the inherent ability of receptors to couple to their cognate G proteins in the absence of ligand, to inform the development of high-throughput screening assays for a particular orphan receptor. We specifically focus on a two-step process, whereby constitutive G protein coupling is first determined using yeast Gpa1/human G protein chimeras linked to growth and β-galactosidase generation. Coupling selectivity is then confirmed in mammalian cells expressing endogenous G proteins and driving accumulation of transcription factor-fused luciferase reporters specific to each of the classes of G protein. Based on these findings, high-throughput screening campaigns can be performed on the already miniaturized mammalian reporter system.

  5. Demonstration of high coupling efficiency to Al capsule in rugby hohlraum on NIF

    Science.gov (United States)

    Ping, Y.; Smalyuk, V.; Amendt, P.; Bennett, D.; Chen, H.; Dewald, E.; Goyon, C.; Graziani, F.; Johnson, S.; Khan, S.; Landen, O.; Nikroo, A.; Pino, J.; Ralph, J.; Seugling, R.; Strozzi, D.; Tipton, R.; Tommasini, R.; Wang, M.; Loomis, E.; Merritt, E.; Montgomery, D.

    2017-10-01

    A new design of the double-shell approach predicts a high coupling efficiency from the hohlraum to the capsule, with 700 kJ in the capsule instead of 200kJ in the conventional low-Z single-shell scheme, improving prospects of double-shell performance. A recent experiment on NIF has evaluated a first step toward this goal of energy coupling using 0.7x subscale Al capsule, Au rugby hohlraum and 1MJ drive. A shell velocity of 150 μm/ns was measured, DANTE peak temperature of 255 eV was measured, and shell kinetic energy of 36 kJ was inferred using a rocket model, all close to predictions and consistent with 330kJ of total energy coupled to the capsule. Data analysis and more results from subsequent experiments will be presented. In the next step, an additional 2x increase of total coupled energy up to 700 kJ is projected for full-scale 2-MJ drive in U Rugby hohlraum. This work was performed under DOE contract DE-AC52-07NA27344.

  6. Highly Efficient Synthesis of 2-Aryl-3-methoxyacrylates via Suzuki-Miyaura Coupling Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Ho; Lee, Chun Ho; Song, Young Seob; Park, No Kyun; Kim, Bum Tae; Heo, Jung Nyoung [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of)

    2006-02-15

    We have developed a highly efficient and convergent synthesis of 2-aryl-3-methoxyacrylates via the Suzuki-Miyaura coupling reaction of α-iodo-β-methoxy-acrylate with arylboronic acids. The biological activities of 2-aryl-3-methoxyacrylate derivatives will be reported in due course. The Suzuki-Miyaura coupling reaction provides a convenient access to the carbon-carbon bond formation with high efficiency. Recently, a number of 2-aryl-3-methoxy-acrylates served as a key scaffold for the development of biologically active pharmaceuticals and agrochemicals. Especially, the discovery of the naturally-occurring fungicides, such as strobilurin A and oudemansin A, possessing a β-methoxyacrylate moiety was immediately seized great attention by industrial research groups to open a new era of the strobilurin family including azoxy-strobin and picoxystrobin.

  7. Degree-degree dependencies in directed networks with heavy-tailed degrees

    NARCIS (Netherlands)

    van der Hoorn, W.L.F.; Litvak, Nelly

    2015-01-01

    In network theory, Pearson’s correlation coefficients are most commonly used to measure the degree assortativity of a network. We investigate the behavior of these coefficients in the setting of directed networks with heavy-tailed degree sequences. We prove that for graphs where the in- and

  8. Effect of coupling asymmetry on mean-field solutions of the direct and inverse Sherrington-Kirkpatrick model

    DEFF Research Database (Denmark)

    Sakellariou, Jason; Roudi, Yasser; Mezard, Marc

    2012-01-01

    We study how the degree of symmetry in the couplings influences the performance of three mean field methods used for solving the direct and inverse problems for generalized Sherrington-Kirkpatrick models. In this context, the direct problem is predicting the potentially time-varying magnetizations...... than the other two approximations, TAP outperforms MF when the coupling matrix is nearly symmetric, while MF works better when it is strongly asymmetric. For the inverse problem, MF performs better than both TAP and nMF, although an ad hoc adjustment of TAP can make it comparable to MF. For high...

  9. Performance and microbial community composition dynamics of aerobic granular sludge from sequencing batch bubble column reactors operated at 20 degrees C, 30 degrees C, and 35 degrees C.

    Science.gov (United States)

    Ebrahimi, Sirous; Gabus, Sébastien; Rohrbach-Brandt, Emmanuelle; Hosseini, Maryam; Rossi, Pierre; Maillard, Julien; Holliger, Christof

    2010-07-01

    Two bubble column sequencing batch reactors fed with an artificial wastewater were operated at 20 degrees C, 30 degrees C, and 35 degrees C. In a first stage, stable granules were obtained at 20 degrees C, whereas fluffy structures were observed at 30 degrees C. Molecular analysis revealed high abundance of the operational taxonomic unit 208 (OTU 208) affiliating with filamentous bacteria Leptothrix spp. at 30 degrees C, an OTU much less abundant at 20 degrees C. The granular sludge obtained at 20 degrees C was used for the second stage during which one reactor was maintained at 20 degrees C and the second operated at 30 degrees C and 35 degrees C after prior gradual increase of temperature. Aerobic granular sludge with similar physical properties developed in both reactors but it had different nutrient elimination performances and microbial communities. At 20 degrees C, acetate was consumed during anaerobic feeding, and biological phosphorous removal was observed when Rhodocyclaceae-affiliating OTU 214 was present. At 30 degrees C and 35 degrees C, acetate was mainly consumed during aeration and phosphorous removal was insignificant. OTU 214 was almost absent but the Gammaproteobacteria-affiliating OTU 239 was more abundant than at 20 degrees C. Aerobic granular sludge at all temperatures contained abundantly the OTUs 224 and 289 affiliating with Sphingomonadaceae indicating that this bacterial family played an important role in maintaining stable granular structures.

  10. Kinetics of highly vibrationally excited O2(X) molecules in inductively-coupled oxygen plasmas

    Science.gov (United States)

    Annušová, Adriana; Marinov, Daniil; Booth, Jean-Paul; Sirse, Nishant; Lino da Silva, Mário; Lopez, Bruno; Guerra, Vasco

    2018-04-01

    The high degree of vibrational excitation of O2 ground state molecules recently observed in inductively coupled plasma discharges is investigated experimentally in more detail and interpreted using a detailed self-consistent 0D global kinetic model for oxygen plasmas. Additional experimental results are presented and used to validate the model. The vibrational kinetics considers vibrational levels up to v = 41 and accounts for electron impact excitation and de-excitation (e-V), vibration-to-translation relaxation (V-T) in collisions with O2 molecules and O atoms, vibration-to-vibration energy exchanges (V-V), excitation of electronically excited states, dissociative electron attachment, and electron impact dissociation. Measurements were performed at pressures of 10–80 mTorr (1.33 and 10.67 Pa) and radio frequency (13.56 MHz) powers up to 500 W. The simulation results are compared with the absolute densities in each O2 vibrational level obtained by high sensitivity absorption spectroscopy measurements of the Schumann–Runge bands for O2(X, v = 4–18), O(3 P) atom density measurements by two-photon absorption laser induced fluorescence (TALIF) calibrated against Xe, and laser photodetachment measurements of the O‑ negative ions. The highly excited O2(X, v) distribution exhibits a shape similar to a Treanor-Gordiets distribution, but its origin lies in electron impact e-V collisions and not in V-V up-pumping, in contrast to what happens in all other molecular gases known to date. The relaxation of vibrational quanta is mainly due to V-T energy-transfer collisions with O atoms and to electron impact dissociation of vibrationally excited molecules, e+O2(X, v)→O(3P)+O(3P).

  11. 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.

  12. CO2LD: An innovation educational project for High Degree Professional Training in Refrigeration

    Directory of Open Access Journals (Sweden)

    Ramon Cabello Lopez

    2013-12-01

    Full Text Available Refrigeration is one of the technology sectors which has suffered most changes in the last twenty years, because of the negative impact of the fluids used in the refrigeration cycles, the refrigerants, due to their impact in the ozone layer and the promotion of the global warming. Due to the negative impacts of the fluids, the European Union has established several directives to restrict the use of refrigerant fluids, causing the need of adaptation of the sector to the new regulations. The adaptation of the refrigeration sector to the new regulations must be done by all agents involved, included the training and education of the future refrigeration technicians. To allow this, the project CO2LD has been developed to introduce the future technology in the High Degree Professional Training in Refrigeration. The objective of the project consisted on introducing more efficient and more sustainable refrigeration systems, R134a/CO2 cascade cycles, in the studies of High Degree Professional Training in Refrigeration, and create a collaborative framework among students, secondary-schools, refrigeration technicians, refrigeration companies and the University to facilitate the know-how transfer. This paper presents the objectives of the project, describes its development and analyses the main conclusions of it.

  13. Precise measurement of coupling strength and high temperature quantum effect in a nonlinearly coupled qubit-oscillator system

    Science.gov (United States)

    Ge, Li; Zhao, Nan

    2018-04-01

    We study the coherence dynamics of a qubit coupled to a harmonic oscillator with both linear and quadratic interactions. As long as the linear coupling strength is much smaller than the oscillator frequency, the long time behavior of the coherence is dominated by the quadratic coupling strength g 2. The coherence decays and revives at a period , with the width of coherence peak decreasing as the temperature increases, hence providing a way to measure g 2 precisely without cooling. Unlike the case of linear coupling, here the coherence dynamics never reduces to the classical limit in which the oscillator is classical. Finally, the validity of linear coupling approximation is discussed and the coherence under Hahn-echo is evaluated.

  14. Dynamic performance analysis of diaphragm coupling base on ABAQUS

    Directory of Open Access Journals (Sweden)

    You Wen

    2017-04-01

    Full Text Available Base on the diaphragm coupling of driving system of a rotation testing machine,FEA software ABAQUS is used to simulate the force which the coupling gets when it is working,to obtain the stress and stain during the coupling with axial misalignment and degree misalignment and to find where the maximal stress is as well as its distribution.Then the nature frequency of the coupling is calculated by use of finite element software and rotor dynamics and compared with the date of misalignment and maximum speed from the manufacture,which verifies the correctness of the model and the reliability of the calculation method.

  15. Surface-Activated Coupling Reactions Confined on a Surface.

    Science.gov (United States)

    Dong, Lei; Liu, Pei Nian; Lin, Nian

    2015-10-20

    -functional theory (DFT) transition-state calculations have been used to shed light on reaction mechanisms and to unravel the trends of different surface materials. In this Account, we discuss recent progress made in two widely studied surface-confined coupling reactions, aryl-aryl (Ullmann-type) coupling and alkyne-alkyne (Glaser-type) coupling, and focus on surface activation effects. Combined experimental and theoretical studies on the same reactions taking place on different metal surfaces have clearly demonstrated that different surfaces not only reduce the reaction barrier differently and render different reaction pathways but also control the morphology of the reaction products and, to some degree, select the reaction products. We end the Account with a list of questions to be addressed in the future. Satisfactorily answering these questions may lead to using the surface-confined coupling reactions to synthesize predefined products with high yield.

  16. Charge-coupled devices for particle detection with high spatial resolution

    International Nuclear Information System (INIS)

    Farley, F.J.; Damerell, C.J.S.; Gillman, A.R.; Wickens, F.J.

    1980-10-01

    The results of a study of the possible application of a thin microelectronic device (the charge-coupled device) to high energy physics as particle detectors with good spatial resolution which can distinguish between tracks emerging from the primary vertex and those from secondary vertices due to the decay of short lived particles with higher flavours, are reported. Performance characteristics indicating the spatial resolution, particle discrimination, time resolution, readout time and lifetime of such detectors have been obtained. (U.K.)

  17. Discrimination of relationships with the same degree of kinship using chromosomal sharing patterns estimated from high-density SNPs.

    Science.gov (United States)

    Morimoto, Chie; Manabe, Sho; Fujimoto, Shuntaro; Hamano, Yuya; Tamaki, Keiji

    2018-03-01

    Distinguishing relationships with the same degree of kinship (e.g., uncle-nephew and grandfather-grandson) is generally difficult in forensic genetics by using the commonly employed short tandem repeat loci. In this study, we developed a new method for discerning such relationships between two individuals by examining the number of chromosomal shared segments estimated from high-density single nucleotide polymorphisms (SNPs). We computationally generated second-degree kinships (i.e., uncle-nephew and grandfather-grandson) and third-degree kinships (i.e., first cousins and great-grandfather-great-grandson) for 174,254 autosomal SNPs considering the effect of linkage disequilibrium and recombination for each SNP. We investigated shared chromosomal segments between two individuals that were estimated based on identity by state regions. We then counted the number of segments in each pair. Based on our results, the number of shared chromosomal segments in collateral relationships was larger than that in lineal relationships with both the second-degree and third-degree kinships. This was probably caused by differences involving chromosomal transitions and recombination between relationships. As we probabilistically evaluated the relationships between simulated pairs based on the number of shared segments using logistic regression, we could determine accurate relationships in >90% of second-degree relatives and >70% of third-degree relatives, using a probability criterion for the relationship ≥0.9. Furthermore, we could judge the true relationships of actual sample pairs from volunteers, as well as simulated data. Therefore, this method can be useful for discerning relationships between two individuals with the same degree of kinship. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Pinning synchronization of hybrid-coupled directed delayed dynamical network via intermittent control.

    Science.gov (United States)

    Cai, Shuiming; Zhou, Peipei; Liu, Zengrong

    2014-09-01

    This paper concerns the problem of exponential synchronization for a class of general delayed dynamical networks with hybrid coupling via pinning periodically intermittent control. Both the internal delay and coupling delay are taken into account in the network model. Meanwhile, the transmission delay and self-feedback delay are involved in the delayed coupling term. By establishing a new differential inequality, several simple and useful exponential synchronization criteria are derived analytically. It is shown that the controlled synchronization state can vary in comparison with the conventional synchronized solution, and the degree of the node and the inner delayed coupling matrix play important roles in the controlled synchronization state. By choosing different inner delayed coupling matrices and the degrees of the node, different controlled synchronization states can be obtained. Furthermore, the detail pinning schemes deciding what nodes should be chosen as pinned candidates and how many nodes are needed to be pinned for a fixed coupling strength are provided. The simple procedures illuminating how to design suitable intermittent controllers in real application are also given. Numerical simulations, including an undirected scale-free network and a directed small-world network, are finally presented to demonstrate the effectiveness of the theoretical results.

  19. Custom ceramic microchannel-cooled array for high-power fiber-coupled application

    Science.gov (United States)

    Junghans, Jeremy; Feeler, Ryan; Stephens, Ed

    2018-03-01

    A low-SWaP (Size, Weight and Power) diode array has been developed for a high-power fiber-coupled application. High efficiency ( 65%) diodes enable high optical powers while minimizing thermal losses. A large amount of waste heat is still generated and must be extracted. Custom ceramic microchannel-coolers (MCCs) are used to dissipate the waste heat. The custom ceramic MCC was designed to accommodate long cavity length diodes and micro-lenses. The coolers provide similar thermal performance as copper MCCs however they are not susceptible to erosion and can be cooled with standard filtered water. The custom ceramic micro-channel cooled array was designed to be a form/fit replacement for an existing copperbased solution. Each array consisted of three-vertically stacked MCCs with 4 mm CL, 976 nm diodes and beamshaping micro-optics. The erosion and corrosion resistance of ceramic array is intended to mitigate the risk of copperbased MCC corrosion failures. Elimination of the water delivery requirements (pH, resistivity and dissolved oxygen control) further reduces the system SWaP while maintaining reliability. The arrays were fabricated and fully characterized. This work discusses the advantages of the ceramic MCC technology and describes the design parameters that were tailored for the fiber-coupled application. Additional configuration options (form/fit, micro-lensing, alternate coolants, etc.) and on-going design improvements are also discussed.

  20. Note: Motor-piezoelectricity coupling driven high temperature fatigue device.

    Science.gov (United States)

    Ma, Z C; Du, X J; Zhao, H W; Ma, X X; Jiang, D Y; Liu, Y; Ren, L Q

    2018-01-01

    The design and performance evaluation of a novel high temperature fatigue device simultaneously driven by servo motor and piezoelectric actuator is our focus. The device integrates monotonic and cyclic loading functions with a maximum tensile load of 1800 N, driving frequency of 50 Hz, alternating load of 95 N, and maximum service temperature of 1200 °C. Multimodal fatigue tests with arbitrary combinations of static and dynamic loads are achieved. At temperatures that range from RT to 1100 °C, the tensile and tensile-fatigue coupling mechanical behaviors of UM Co50 alloys are investigated to verify the feasibility of the device.

  1. A methodology for analysing lateral coupled behavior of high speed railway vehicles and structures

    International Nuclear Information System (INIS)

    AntolIn, P; Goicolea, J M; Astiz, M A; Alonso, A

    2010-01-01

    Continuous increment of the speed of high speed trains entails the increment of kinetic energy of the trains. The main goal of this article is to study the coupled lateral behavior of vehicle-structure systems for high speed trains. Non linear finite element methods are used for structures whereas multibody dynamics methods are employed for vehicles. Special attention must be paid when dealing with contact rolling constraints for coupling bridge decks and train wheels. The dynamic models must include mixed variables (displacements and creepages). Additionally special attention must be paid to the contact algorithms adequate to wheel-rail contact. The coupled vehicle-structure system is studied in a implicit dynamic framework. Due to the presence of very different systems (trains and bridges), different frequencies are involved in the problem leading to stiff systems. Regarding to contact methods, a main branch is studied in normal contact between train wheels and bridge decks: penalty method. According to tangential contact FastSim algorithm solves the tangential contact at each time step solving a differential equation involving relative displacements and creepage variables. Integration for computing the total forces in the contact ellipse domain is performed for each train wheel and each solver iteration. Coupling between trains and bridges requires a special treatment according to the kinetic constraints imposed in the wheel-rail pair and the load transmission. A numerical example is performed.

  2. A methodology for analysing lateral coupled behavior of high speed railway vehicles and structures

    Science.gov (United States)

    Antolín, P.; Goicolea, J. M.; Astiz, M. A.; Alonso, A.

    2010-06-01

    Continuous increment of the speed of high speed trains entails the increment of kinetic energy of the trains. The main goal of this article is to study the coupled lateral behavior of vehicle-structure systems for high speed trains. Non linear finite element methods are used for structures whereas multibody dynamics methods are employed for vehicles. Special attention must be paid when dealing with contact rolling constraints for coupling bridge decks and train wheels. The dynamic models must include mixed variables (displacements and creepages). Additionally special attention must be paid to the contact algorithms adequate to wheel-rail contact. The coupled vehicle-structure system is studied in a implicit dynamic framework. Due to the presence of very different systems (trains and bridges), different frequencies are involved in the problem leading to stiff systems. Regarding to contact methods, a main branch is studied in normal contact between train wheels and bridge decks: penalty method. According to tangential contact FastSim algorithm solves the tangential contact at each time step solving a differential equation involving relative displacements and creepage variables. Integration for computing the total forces in the contact ellipse domain is performed for each train wheel and each solver iteration. Coupling between trains and bridges requires a special treatment according to the kinetic constraints imposed in the wheel-rail pair and the load transmission. A numerical example is performed.

  3. Design and experimental investigation of a magnetically coupled vibration energy harvester using two inverted piezoelectric cantilever beams for rotational motion

    International Nuclear Information System (INIS)

    Zou, Hong-Xiang; Zhang, Wen-ming; Li, Wen-Bo; Wei, Ke-Xiang; Gao, Qiu-Hua; Peng, Zhi-Ke; Meng, Guang

    2017-01-01

    Highlights: • A magnetically coupled two-degree-of-freedom harvester for rotation is proposed. • The electromechanical coupling model is developed and validated experimentally. • The harvester can generate high voltage at low rotating speeds. • The harvester can harvest vibration energy in multiple frequency bands. - Abstract: Energy can be harvested from rotational motion for powering wireless autonomous electronic devices. The paper presents a magnetically coupled two-degree-of-freedom vibration energy harvester for rotary motion applications. The design consists of two inverted piezoelectric cantilever beams whose free ends point to the rotating shaft. The centrifugal force of the inverted cantilever beam is beneficial to producing large amplitude in a low speed range. The electromechanical coupling dynamical model is developed by the energy method from Hamilton’s principle and validated experimentally. The experimental results indicate that the presented harvester is suitable for low speed rotation and can harvest vibration energy in multiple frequency bands. The first and second resonant behaviors of voltage can be obtained at 420 r/min and 550 r/min, and the average output powers are 564 μW and 535.3 μW, respectively.

  4. Lens positioner with five degrees of freedom

    International Nuclear Information System (INIS)

    Kobierecki, M.W.; Rienecker, F. Jr.

    1978-01-01

    A device for positioning lenses precisely with five degrees of freedom (three translations and two angular rotations). The unique features of the device are its compact design, large clear aperture, and high degree of positioning accuracy combined with five degrees of freedom in axis motion. Thus, the device provides precision and flexibility in positioning of optical components

  5. High voltage high brightness electron accelerators with MITL voltage adder coupled to foilless diodes

    International Nuclear Information System (INIS)

    Mazarakis, M.G.; Poukey, J.W.; Frost, C.A.; Shope, S.L.; Halbleib, J.A.; Turman, B.N.

    1993-01-01

    During the last ten years the authors have extensively studied the physics and operation of magnetically-immersed electron foilless diodes. Most of these sources were utilized as injectors to high current, high energy linear induction accelerators such as those of the RADLAC family. Recently they have experimentally and theoretically demonstrated that foilless diodes can be successfully coupled to self-magnetically insulated transmission line voltage adders to produce very small high brightness, high definition (no halo) electron beams. The RADLAC/SMILE experience opened the path to a new approach in high brightness, high energy induction accelerators. There is no beam drifting through the device. The voltage addition occurs in a center conductor, and the beam is created at the high voltage end in an applied magnetic field diode. This work was motivated by the remarkable success of the HERMES-III accelerator and the need to produce small radius, high energy, high current electron beams for air propagation studies and flash x-ray radiography. In this paper they present experimental results compared with analytical and numerical simulations in addition to design examples of devices that can produce multikiloamp electron beams of as high as 100 MV energies and radii as small as 1 mm

  6. Astronomy Enrollments and Degrees: Results from the 2012 Survey of Astronomy Enrollments and Degrees. Focus On

    Science.gov (United States)

    Mulvey, Patrick; Nicholson, Starr

    2014-01-01

    Interest in astronomy degrees in the U.S. remains strong, with astronomy enrollments at or near all-time highs for the 2012-13 academic year. The total number of students taking an introductory astronomy course at a degree-granting physics or astronomy department is approaching 200,000. Enrollments in introductory astronomy courses have been…

  7. Large-degree asymptotics of rational Painlevé-II functions: noncritical behaviour

    International Nuclear Information System (INIS)

    Buckingham, Robert J; Miller, Peter D

    2014-01-01

    Rational solutions of the inhomogeneous Painlevé-II equation and of a related coupled Painlevé-II system have recently arisen in studies of fluid vortices and of the sine-Gordon equation. For the sine-Gordon application in particular it is of interest to understand the large-degree asymptotic behaviour of the rational Painlevé-II functions. We explicitly compute the leading-order large-degree asymptotics of these two families of rational functions valid in the whole complex plane with the exception of a neighbourhood of a certain piecewise-smooth closed curve. We obtain rigorous error bounds by using the Deift–Zhou nonlinear steepest-descent method for Riemann–Hilbert problems. (paper)

  8. Relation of extended Van Hove singularities to high-temperature superconductivity within strong-coupling theory

    International Nuclear Information System (INIS)

    Radtke, R.J.; Norman, M.R.

    1994-01-01

    Recent angle-resolved photoemission (ARPES) experiments have indicated that the electronic dispersion in some of the cuprates possesses an extended saddle point near the Fermi level which gives rise to a density of states that diverges like a power law instead of the weaker logarithmic divergence usually considered. We investigate whether this strong singularity can give rise to high transition temperatures by computing the critical temperature T c and isotope effect coefficient α within a strong-coupling Eliashberg theory which accounts for the full energy variation of the density of states. Using band structures extracted from ARPES measurements, we demonstrate that, while the weak-coupling solutions suggest a strong influence of the strength of the Van Hove singularity on T c and α, strong-coupling solutions show less sensitivity to the singularity strength and do not support the hypothesis that band-structure effects alone can account for either the large T c 's or the different T c 's within the copper oxide family. This conclusion is supported when our results are plotted as a function of the physically relevant self-consistent coupling constant, which shows universal behavior at very strong coupling

  9. Deterministic Diffusion in Delayed Coupled Maps

    International Nuclear Information System (INIS)

    Sozanski, M.

    2005-01-01

    Coupled Map Lattices (CML) are discrete time and discrete space dynamical systems used for modeling phenomena arising in nonlinear systems with many degrees of freedom. In this work, the dynamical and statistical properties of a modified version of the CML with global coupling are considered. The main modification of the model is the extension of the coupling over a set of local map states corresponding to different time iterations. The model with both stochastic and chaotic one-dimensional local maps is studied. Deterministic diffusion in the CML under variation of a control parameter is analyzed for unimodal maps. As a main result, simple relations between statistical and dynamical measures are found for the model and the cases where substituting nonlinear lattices with simpler processes is possible are presented. (author)

  10. Metal-etching-free direct delamination and transfer of single-layer graphene with a high degree of freedom.

    Science.gov (United States)

    Yang, Sang Yoon; Oh, Joong Gun; Jung, Dae Yool; Choi, HongKyw; Yu, Chan Hak; Shin, Jongwoo; Choi, Choon-Gi; Cho, Byung Jin; Choi, Sung-Yool

    2015-01-14

    A method of graphene transfer without metal etching is developed to minimize the contamination of graphene in the transfer process and to endow the transfer process with a greater degree of freedom. The method involves direct delamination of single-layer graphene from a growth substrate, resulting in transferred graphene with nearly zero Dirac voltage due to the absence of residues that would originate from metal etching. Several demonstrations are also presented to show the high degree of freedom and the resulting versatility of this transfer method. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Progress toward coupled flux qubits with high connectivity and long coherence times

    Science.gov (United States)

    Weber, Steven; Hover, David; Rosenberg, Danna; Samach, Gabriel; Yoder, Jonilyn; Kerman, Andrew; Oliver, William

    The ability to engineer interactions between qubits is essential to all areas of quantum information science. The capability to tune qubit-qubit couplings in situ is desirable for gate-based quantum computing and analog quantum simulation and necessary for quantum annealing. Consequently, tunable coupling has been the subject of several experimental efforts using both transmon qubits and flux qubits. Recently, our group has demonstrated robust and long-lived capacitively shunted (C-shunt) flux qubits. Here, we discuss our efforts to develop architectures for tunably coupling these qubits. In particular, we focus on optimizing the RF SQUID coupler to achieve high connectivity. This research was funded by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA) and by the Assistant Secretary of Defense for Research & Engineering under Air Force Contract No. FA8721-05-C-0002. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of ODNI, IARPA, or the US Government.

  12. Quest to validate and define performance for the high volume metallic stator PCP at 250 degrees Celsius

    Energy Technology Data Exchange (ETDEWEB)

    Noonan, S.G. [ConocoPhillips Co., Houston, TX (United States); Klaczek, W.; Piers, K. [C-FER Technologies, Edmonton, AB (Canada); Seince, L. [PCM USA Inc., Houston, TX (United States); Jahn, S. [Kudu Industries, Calgary, AB (Canada)

    2008-10-15

    ConocoPhillips has been searching for a high volume artificial lift system that will reliably operate in a 250 degree Celsius downhole environment to meet the needs of steam assisted gravity drainage (SAGD) operations. This paper described the complexity of building and operating a high temperature flow loop rated for 250 degrees Celsius. It also described the lessons learned while upgrading an existing flow loop, from the initial design, procurement and construction through to the final commissioning phases. The paper described the issues encountered with the first artificial lit system tested at 250 degrees Celsius. The system consisted of a metallic progressing cavity pump system rated for 6919 barrels per day at 500 rotations per minute. The final upgraded capabilities of the flow loop were also listed. Images of the upgraded flow loop were also provided. It was concluded that the test program not only served to validate and define the pump's performance, but also provided valuable lessons on the completion configuration and operational procedures. Testing new artificial lift technology in a controlled flow loop, rather than in field installation, provided the opportunity to test these pumping systems under a large variety of conditions to truly understand the performance and limitations of each pump. 3 refs., 1 tab., 5 figs.

  13. Strongly coupled semidirect mediation of supersymmetry breaking

    International Nuclear Information System (INIS)

    Ibe, M.; Izawa, K.-I.; Nakai, Y.

    2009-01-01

    Strongly coupled semidirect gauge mediation models of supersymmetry breaking through massive mediators with standard-model charges are investigated by means of composite degrees of freedom. Sizable mediation is realized to generate the standard-model gaugino masses for a small mediator mass without breaking the standard-model symmetries.

  14. Influence of coupling parameter on current-voltage characteristics of intrinsic Josephson junctions in high-T c superconductors

    International Nuclear Information System (INIS)

    Shukrinov, Yu.M.; Mahfouzi, F.

    2006-01-01

    We study the current-voltage characteristics of intrinsic Josephson junctions in high-T c superconductors by numerical calculations and in framework of capacitively coupled Josephson junctions model we obtain the total number of branches. The influence of the coupling parameter α on the current-voltage characteristics at fixed parameter β (β 2 1/β c , where β c is McCumber parameter) and the influence of α on β-dependence of the current-voltage characteristics are investigated. We obtain the α-dependence of the branch's slopes and branch's endpoints. The presented results show new features of the coupling effect on the scheme of hysteresis jumps in current-voltage characteristics of intrinsic Josephson junctions in high-T c superconductors

  15. The construction of a model of the process of couples' forgiveness in emotion-focused therapy for couples.

    Science.gov (United States)

    Meneses, Catalina Woldarsky; Greenberg, Leslie S

    2011-10-01

    This study explored how forgiveness unfolds in the context of emotion-focused couples therapy (EFT-C) in eight cases of women betrayed by their partners. Forgiveness was defined as a process involving the reduction in negative feelings and the giving out of undeserved compassion. This was measured by changes in the pre- and posttreatment scores on the Enright Forgiveness Inventory, the Unfinished Business Resolution Scale, and a single item directly asking respondents to indicate their degree of forgiveness. A task analysis was performed to rigorously track the steps leading to forgiveness using videotapes of therapy sessions for eight couples. The performance of the four couples who forgave were compared with each other and then contrasted with the performance of another four couples who did not reach forgiveness at the end of therapy. Based on these observations, a model of the process of forgiveness in EFT-C and a process rating system were developed. © 2011 American Association for Marriage and Family Therapy.

  16. A new soft-switched high step-up DC-DC converter with dual coupled inductors

    DEFF Research Database (Denmark)

    Forouzesh, Mojtaba; Shen, Yanfeng; Yari, Keyvan

    2017-01-01

    This paper introduces a new efficient high step-up dc-dc converter with a shared input path and dual series coupled inductors at the output. This converter is suitable for high power applications due to its shared input current that puts low current stresses on the low voltage side switches...

  17. Modeling interacting dynamic networks: I. Preferred degree networks and their characteristics

    International Nuclear Information System (INIS)

    Liu, Wenjia; Schmittmann, Beate; Zia, R K P; Jolad, Shivakumar

    2013-01-01

    We study a simple model of dynamic networks, characterized by a set preferred degree, κ. Each node with degree k attempts to maintain its κ and will add (cut) a link with probability w(k;κ) (1 − w(k;κ)). As a starting point, we consider a homogeneous population, where each node has the same κ, and examine several forms of w(k;κ), inspired by Fermi–Dirac functions. Using Monte Carlo simulations, we find the degree distribution in the steady state. In contrast to the well known Erdős–Rényi network, our degree distribution is not a Poisson distribution; yet its behavior can be understood by an approximate theory. Next, we introduce a second preferred degree network and couple it to the first by establishing a controllable fraction of inter-group links. For this model, we find both understandable and puzzling features. Generalizing the prediction for the homogeneous population, we are able to explain the total degree distributions well, but not the intra- or inter-group degree distributions. When monitoring the total number of inter-group links, X, we find very surprising behavior. X explores almost the full range between its maximum and minimum allowed values, resulting in a flat steady-state distribution, reminiscent of a simple random walk confined between two walls. Both simulation results and analytic approaches will be discussed. (paper)

  18. Behaviour of coupling constants at high temperature in supersymmetric theories

    International Nuclear Information System (INIS)

    Swee Ping Chia.

    1986-04-01

    An analysis is presented of the temperature dependence of the coupling constants using the improved one-loop approximation in the Wess-Zumino model and the supersymmetric O(N) model. It is found that all the coupling constants, both bosonic (Φ 4 type) and Yukawa, approach constant nonzero values as T→∞. The asymptotic values of the bosonic couplings are slightly smaller than the corresponding zero-temperature values, and those of the Yukawa couplings are the same as the zero-temperature values. (author)

  19. High-Performance Modeling of Carbon Dioxide Sequestration by Coupling Reservoir Simulation and Molecular Dynamics

    KAUST Repository

    Bao, Kai; Yan, Mi; Allen, Rebecca; Salama, Amgad; Lu, Ligang; Jordan, Kirk E.; Sun, Shuyu; Keyes, David E.

    2015-01-01

    The present work describes a parallel computational framework for carbon dioxide (CO2) sequestration simulation by coupling reservoir simulation and molecular dynamics (MD) on massively parallel high-performance-computing (HPC) systems

  20. Nanocellulose coupled flexible polypyrrole@graphene oxide composite paper electrodes with high volumetric capacitance

    Science.gov (United States)

    Wang, Zhaohui; Tammela, Petter; Strømme, Maria; Nyholm, Leif

    2015-02-01

    A robust and compact freestanding conducting polymer-based electrode material based on nanocellulose coupled polypyrrole@graphene oxide paper is straightforwardly prepared via in situ polymerization for use in high-performance paper-based charge storage devices, exhibiting stable cycling over 16 000 cycles at 5 A g-1 as well as the largest specific volumetric capacitance (198 F cm-3) so far reported for flexible polymer-based electrodes.A robust and compact freestanding conducting polymer-based electrode material based on nanocellulose coupled polypyrrole@graphene oxide paper is straightforwardly prepared via in situ polymerization for use in high-performance paper-based charge storage devices, exhibiting stable cycling over 16 000 cycles at 5 A g-1 as well as the largest specific volumetric capacitance (198 F cm-3) so far reported for flexible polymer-based electrodes. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr07251k

  1. Scalable production of Cu@C composites for cross-coupling catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Lijuan [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081 (China); Ming, Hai, E-mail: lunaticmh@163.com [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China)

    2015-10-15

    Highlights: • Cu@C core–shell composite was prepared by reduction of [Cu(NH{sub 3}){sub 4}]{sup 2+} with glucose. • The carbon shell in Cu@C can be tuned to the different degree of carbonization. • The Cu@C composites were utilized to catalyze the C−N cross coupling reaction. • The catalytic ability of Cu@C depends on the degree of shell-carbonization. - Abstract: A novel Cu@C core–shell microstructure was prepared by reduction of [Cu(NH{sub 3}){sub 4}]{sup 2+} with glucose using a mild hydrothermal process. The carbon shell of such Cu@C composite can be tuned to different carbonization degrees just through varying the calcination conditions. The structural properties of as-prepared Cu@C were investigated in detail by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron micrographs (TEM) and Raman spectra. In addition, these Cu@C composites were firstly used to catalyze the C−N cross coupling of amines with iodobenzene. Among them, the catalytic ability of Cu@C composites increased as their surface carbon’s carburization degree improved.

  2. Coherent regimes of globally coupled dynamical systems

    DEFF Research Database (Denmark)

    de Monte, Silvia; D'ovidio, Francesco; Mosekilde, Erik

    2003-01-01

    This Letter presents a method by which the mean field dynamics of a population of dynamical systems with parameter diversity and global coupling can be described in terms of a few macroscopic degrees of freedom. The method applies to populations of any size and functional form in the region...

  3. Simultaneous determination of 13 carbohydrates using high-performance anion-exchange chromatography coupled with pulsed amperometric detection and mass spectrometry.

    Science.gov (United States)

    Zhao, Dan; Feng, Feng; Yuan, Fei; Su, Jin; Cheng, Yan; Wu, Hanqiu; Song, Kun; Nie, Bo; Yu, Lian; Zhang, Feng

    2017-04-01

    A simple, accurate, and highly sensitive method was developed for the determination of 13 carbohydrates in polysaccharide of Spirulina platensis based on high-performance anion-exchange chromatography coupled with pulsed amperometric detection and mass spectrometry. Samples were extracted with deionized water using ultrasonic-assisted extraction, and the ultrasound-assisted extraction conditions were optimized by Box-Behnken design. Then the extracted polysaccharide was hydrolyzed by adding 1 mol/L trifluoroacetic acid before determination by high-performance anion-exchange chromatography coupled with pulsed amperometric detection and confirmed by high-performance anion-exchange chromatography coupled with mass spectrometry. The high-performance anion-exchange chromatography coupled with pulsed amperometric detection method was performed on a CarboPac PA20 column by gradient elution using deionized water, 0.1 mol/L sodium hydroxide solution, and 0.4 mol/L sodium acetate solution. Excellent linearity was observed in the range of 0.05-10 mg/L. The average recoveries ranged from 80.7 to 121.7%. The limits of detection and limits of quantification for 13 carbohydrates were 0.02-0.10 and 0.2-1.2  μg/kg, respectively. The developed method has been successfully applied to ambient samples, and the results indicated that high-performance anion-exchange chromatography coupled with pulsed amperometric detection and mass spectrometry could provide a rapid and accurate method for the simultaneous determination of carbohydrates. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Evaluation and analysis on the coupling performance of a high-speed turboexpander compressor

    Science.gov (United States)

    Chen, Shuangtao; Fan, Yufeng; Yang, Shanju; Chen, Xingya; Hou, Yu

    2017-12-01

    A high-speed turboexpander compressor (TEC) for small reverse Brayton air refrigerator is tested and analyzed in the present work. A TEC consists of an expander and a compressor, which are coupled together and interact with each other directly. Meanwhile, the expander and compressor have different effects on the refrigerator. The TEC overall efficiency, which contains effects of the expander's expansion, the compressor's pre-compression, and the pressure drop between them, was proved. It unifies influences of both compression and expansion processes on the COP of refrigerator and could be used to evaluate the TEC overall performance. Then, the coupling parameters were analyzed, which shows that for a TEC, the expander efficiency should be fully utilized first, followed by the compressor pressure ratio. Experiments were carried out to test the TEC coupling performances. The results indicated that, the TEC overall efficiency could reach 67.2%, and meanwhile 22.3% of the energy output was recycled.

  5. Artificial dispersion via high-order homogenization: magnetoelectric coupling and magnetism from dielectric layers

    Science.gov (United States)

    Liu, Yan; Guenneau, Sébastien; Gralak, Boris

    2013-01-01

    We investigate a high-order homogenization (HOH) algorithm for periodic multi-layered stacks. The mathematical tool of choice is a transfer matrix method. Expressions for effective permeability, permittivity and magnetoelectric coupling are explored by frequency power expansions. On the physical side, this HOH uncovers a magnetoelectric coupling effect (odd-order approximation) and artificial magnetism (even-order approximation) in moderate contrast photonic crystals. Comparing the effective parameters' expressions of a stack with three layers against that of a stack with two layers, we note that the magnetoelectric coupling effect vanishes while the artificial magnetism can still be achieved in a centre-symmetric periodic structure. Furthermore, we numerically check the effective parameters through the dispersion law and transmission property of a stack with two dielectric layers against that of an effective bianisotropic medium: they are in good agreement throughout the low-frequency (acoustic) band until the first stop band, where the analyticity of the logarithm function of the transfer matrix () breaks down. PMID:24101891

  6. Large spin relaxation anisotropy and valley-Zeeman spin-orbit coupling in WSe2/graphene/h -BN heterostructures

    Science.gov (United States)

    Zihlmann, Simon; Cummings, Aron W.; Garcia, Jose H.; Kedves, Máté; Watanabe, Kenji; Taniguchi, Takashi; Schönenberger, Christian; Makk, Péter

    2018-02-01

    Large spin-orbital proximity effects have been predicted in graphene interfaced with a transition-metal dichalcogenide layer. Whereas clear evidence for an enhanced spin-orbit coupling has been found at large carrier densities, the type of spin-orbit coupling and its relaxation mechanism remained unknown. We show an increased spin-orbit coupling close to the charge neutrality point in graphene, where topological states are expected to appear. Single-layer graphene encapsulated between the transition-metal dichalcogenide WSe2 and h -BN is found to exhibit exceptional quality with mobilities as high as 1 ×105 cm2 V-1 s-1. At the same time clear weak antilocalization indicates strong spin-orbit coupling, and a large spin relaxation anisotropy due to the presence of a dominating symmetric spin-orbit coupling is found. Doping-dependent measurements show that the spin relaxation of the in-plane spins is largely dominated by a valley-Zeeman spin-orbit coupling and that the intrinsic spin-orbit coupling plays a minor role in spin relaxation. The strong spin-valley coupling opens new possibilities in exploring spin and valley degree of freedom in graphene with the realization of new concepts in spin manipulation.

  7. Multiscality in the Dynamics of Coupled Chaotic Systems

    DEFF Research Database (Denmark)

    Pavlov, A.N.; Sosnovtseva, Olga; Ziganshin, A.R.

    2002-01-01

    We investigate the scaling features of complex motions in systems of two coupled chaotic oscillators by means of the wavelet-transform modulus maxima method and the detrended fluctuation analysis. We show that the transition from asynchronous to synchronous dynamics typically reduces the degree...

  8. High-Tc superconducting antenna-coupled microbolometer on silicon

    Science.gov (United States)

    Rice, Joseph P.; Grossman, Erich N.; Borcherdt, L. J.; Rudman, D. A.

    1994-05-01

    A process is described for fabricating antenna-coupled resistive-edge microbolometers based on the high-Tc superconductor YBa2Cu3O7 (YBCO) on silicon. The YBCO and a buffer layer of yttria-stabilized zirconia (YSZ) were grown epitaxially on silicon to minimize excess electrical noise. A silicon-micromachined YBCO/YSZ air-bridge was incorporated to minimize the thermal conductance and the heat capacity. The thermal conductance of the air-bridge was measured to be 3 X 10-6 W/K at a temperature of 100 K. At an operating temperature of 89 K, the detector is estimated to have a response time of 2 microsecond(s) , a responsivity of the 1000 V/W range, and a noise-equivalent power in the 10-12 W/Hz1/2 range at 1000 Hz.

  9. ICRF [Ion Cyclotron Range of Frequencies] heating and antenna coupling in a high beta tokamak

    International Nuclear Information System (INIS)

    Elet, R.S.

    1988-01-01

    Maxwell's Equations are solved in two-dimensions for the electromagnetic fields in a toroidal cavity using the cold plasma fluid dielectric tensor in the Ion Cyclotron Range of Frequencies (ICRF). The Vector Wave Equation is transformed to a set of two, coupled second-order partial differential equations with inhomogeneous forcing functions which model a wave launcher. The resulting equations are finite differenced and solved numerically with a complex banded matrix algorithm on a Cray-2 computer using a code described in this report. This code is used to study power coupling characteristics of a wave launcher for low and high beta tokamaks. The low and high beta equilibrium tokamak magnetic fields applied in this model are determined from analytic solutions to the Grad-Shafranov equation. The code shows good correspondence with the results of low field side ICRF heating experiments performed on the Tokamak of Fontenay-Aux-Roses (TFR). Low field side and high field side antenna coupling properties for ICRF heating in the Columbia High Beta Tokamak (HBT) experiment are calculated with this code. Variations of antenna position in the tokamak, ionic concentration and plasma density, and volume-averaged beta have been analyzed for HBT. It is found that the location of the antenna with respect to the plasma has the dominant role in the design of an ICRF heating experiment in HBT. 10 refs., 52 figs., 13 tabs

  10. [Production of sugar syrup containing rare sugar using dual-enzyme coupled reaction system].

    Science.gov (United States)

    Han, Wenjia; Zhu, Yueming; Bai, Wei; Izumori, Ken; Zhang, Tongcun; Sun, Yuanxia

    2014-01-01

    Enzymatic conversion is very important to produce functional rare sugars, but the conversion rate of single enzymes is generally low. To increase the conversion rate, a dual-enzyme coupled reaction system was developed. Dual-enzyme coupled reaction system was constructed using D-psicose-3-epimerase (DPE) and L-rhamnose isomerase (L-RhI), and used to convert D-fructose to D-psicose and D-allose. The ratio of DPE and L-RhI was 1:10 (W/W), and the concentration of DPE was 0.05 mg/mL. The optimum temperature was 60 degrees C and pH was 9.0. When the concentration of D-fructose was 2%, the reaction reached its equilibrium after 10 h, and the yield of D-psicose and D-allose was 5.12 and 2.04 g/L, respectively. Using the dual-enzymes coupled system developed in the current study, we could obtain sugar syrup containing functional rare sugar from fructose-rich raw material, such as high fructose corn syrup.

  11. Low-to-high refractive index contrast transition (RICT) device for low loss polymer-based optical coupling

    Science.gov (United States)

    Calabretta, N.; Cooman, I. A.; Stabile, R.

    2018-04-01

    We propose for the first time a coupling device concept for passive low-loss optical coupling, which is compatible with the ‘generic’ indium phosphide (InP) multi-project-wafer manufacturing. A low-to-high vertical refractive index contrast transition InP waveguide is designed and tapered down to adiabatically couple light into a top polymer waveguide. The on-chip embedded polymer waveguide is engineered at the chip facets for offering refractive-index and spot-size-matching to silica fiber-arrays. Numerical analysis shows that coupling losses lower than 1.5 dB can be achieved for a TE-polarized light between the InP waveguide and the on-chip embedded polymer waveguide at 1550 nm wavelength. The performance is mainly limited by the difficulty to control single-mode operation. However, coupling losses lower than 1.9 dB can be achieved for a bandwidth as large as 200 nm. Moreover, the foreseen fabrication process steps are indicated, which are compatible with the ‘generic’ InP multi-project-wafer manufacturing. A fabrication error tolerance study is performed, indicating that fabrication errors occur only in 0.25 dB worst case excess losses, as long as high precision lithography is used. The obtained results are promising and may open the route to large port counts and cheap packaging of InP-based photonic integrated chips.

  12. Disrupted pregnancies? How doctors, sonographers and pregnant couples negotiate high risk for Down’s syndrome – a qualitative study

    DEFF Research Database (Denmark)

    Lou, Stina; Hvidman, Lone; Petersen, Olav Bjørn

    2012-01-01

    that 90–95% of the high-risk couples carry a foetus with normal chromosomes. How do these couples frame the disruption caused by the high risk category? Are they able to return to a ‘normal’ pregnancy or does the disruption cause subsequent worry? In the presentation, we will reflect on this important...

  13. Magnetic field control of 90 Degree-Sign , 180 Degree-Sign , and 360 Degree-Sign domain wall resistance

    Energy Technology Data Exchange (ETDEWEB)

    Majidi, Roya, E-mail: royamajidi@gmail.com [Department of Physics, Shahid Rajaee Teacher Training University, Lavizan, 16788-15811 Tehran (Iran, Islamic Republic of)

    2012-10-01

    In the present work, we have compared the resistance of the 90 Degree-Sign , 180 Degree-Sign , and 360 Degree-Sign domain walls in the presence of external magnetic field. The calculations are based on the Boltzmann transport equation within the relaxation time approximation. One-dimensional Neel-type domain walls between two domains whose magnetization differs by angle of 90 Degree-Sign , 180 Degree-Sign , and 360 Degree-Sign are considered. The results indicate that the resistance of the 360 Degree-Sign DW is more considerable than that of the 90 Degree-Sign and 180 Degree-Sign DWs. It is also found that the domain wall resistance can be controlled by applying transverse magnetic field. Increasing the strength of the external magnetic field enhances the domain wall resistance. In providing spintronic devices based on magnetic nanomaterials, considering and controlling the effect of domain wall on resistivity are essential.

  14. Modeling real shim fields for very high degree (and order) B0 shimming of the human brain at 9.4 T.

    Science.gov (United States)

    Chang, Paul; Nassirpour, Sahar; Henning, Anke

    2018-01-01

    To describe the process of calibrating a B 0 shim system using high-degree (or high order) spherical harmonic models of the measured shim fields, to provide a method that considers amplitude dependency of these models, and to show the advantage of very high-degree B 0 shimming for whole-brain and single-slice applications at 9.4 Tesla (T). An insert shim with up to fourth and partial fifth/sixth degree (order) spherical harmonics was used with a Siemens 9.4T scanner. Each shim field was measured and modeled as input for the shimming algorithm. Optimal shim currents can therefore be calculated in a single iteration. A range of shim currents was used in the modeling to account for possible amplitude nonlinearities. The modeled shim fields were used to compare different degrees of whole-brain B 0 shimming on healthy subjects. The ideal shim fields did not correctly shim the subject brains. However, using the modeled shim fields improved the B 0 homogeneity from 55.1 (second degree) to 44.68 Hz (partial fifth/sixth degree) on the whole brains of 9 healthy volunteers, with a total applied current of 0.77 and 6.8 A, respectively. The necessity of calibrating the shim system was shown. Better B 0 homogeneity drastically reduces signal dropout and distortions for echo-planar imaging, and significantly improves the linewidths of MR spectroscopy imaging. Magn Reson Med 79:529-540, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  15. Mixed-Degree Spherical Simplex-Radial Cubature Kalman Filter

    Directory of Open Access Journals (Sweden)

    Shiyuan Wang

    2017-01-01

    Full Text Available Conventional low degree spherical simplex-radial cubature Kalman filters often generate low filtering accuracy or even diverge for handling highly nonlinear systems. The high-degree Kalman filters can improve filtering accuracy at the cost of increasing computational complexity; nevertheless their stability will be influenced by the negative weights existing in the high-dimensional systems. To efficiently improve filtering accuracy and stability, a novel mixed-degree spherical simplex-radial cubature Kalman filter (MSSRCKF is proposed in this paper. The accuracy analysis shows that the true posterior mean and covariance calculated by the proposed MSSRCKF can agree accurately with the third-order moment and the second-order moment, respectively. Simulation results show that, in comparison with the conventional spherical simplex-radial cubature Kalman filters that are based on the same degrees, the proposed MSSRCKF can perform superior results from the aspects of filtering accuracy and computational complexity.

  16. Microscopic theory for coupled atomistic magnetization and lattice dynamics

    Science.gov (United States)

    Fransson, J.; Thonig, D.; Bessarab, P. F.; Bhattacharjee, S.; Hellsvik, J.; Nordström, L.

    2017-12-01

    A coupled atomistic spin and lattice dynamics approach is developed which merges the dynamics of these two degrees of freedom into a single set of coupled equations of motion. The underlying microscopic model comprises local exchange interactions between the electron spin and magnetic moment and the local couplings between the electronic charge and lattice displacements. An effective action for the spin and lattice variables is constructed in which the interactions among the spin and lattice components are determined by the underlying electronic structure. In this way, expressions are obtained for the electronically mediated couplings between the spin and lattice degrees of freedom, besides the well known interatomic force constants and spin-spin interactions. These former susceptibilities provide an atomistic ab initio description for the coupled spin and lattice dynamics. It is important to notice that this theory is strictly bilinear in the spin and lattice variables and provides a minimal model for the coupled dynamics of these subsystems and that the two subsystems are treated on the same footing. Questions concerning time-reversal and inversion symmetry are rigorously addressed and it is shown how these aspects are absorbed in the tensor structure of the interaction fields. By means of these results regarding the spin-lattice coupling, simple explanations of ionic dimerization in double-antiferromagnetic materials, as well as charge density waves induced by a nonuniform spin structure, are given. In the final parts, coupled equations of motion for the combined spin and lattice dynamics are constructed, which subsequently can be reduced to a form which is analogous to the Landau-Lifshitz-Gilbert equations for spin dynamics and a damped driven mechanical oscillator for the ionic motion. It is important to notice, however, that these equations comprise contributions that couple these descriptions into one unified formulation. Finally, Kubo-like expressions for

  17. The Desire of Parenthood: Intuitive Co-parental Behaviors and Quality of Couple Relationship among Italian and Belgian Same-Sex and Opposite-Sex Couples

    Science.gov (United States)

    Miscioscia, Marina; Blavier, Adelaide; Pagone, Paolo R.; Simonelli, Alessandra

    2017-01-01

    Studies that focused on family issues have allowed a great understanding of the aspects related to its subsystems, such as parenting desire and its expectations, couples’ satisfaction and quality of child’s outcomes. All these aspects are greatly interconnected and contribute to the creation of specific family dynamics, such as the quality of family interactions. The present study focuses on intuitive co-parental behaviors and the quality of couple relationship observed during the decision process (intention and desire) to be (or become) parents. Our first goal was to explore these aspects in a cross-national sample made of Italian and Belgian heterosexual, lesbian and gay couples. We then aimed to evaluate if the degree of internalized homophobia affects co-parental alliance. The quality of couple relationship and co-parental behaviors have been evaluated through the recruitment of a group of 115 stable heterosexual, gay and lesbian couples (230 individuals, 20–50 years of age) without children, who wanted to become parents. We used the Prenatal Lausanne Trilogue Play to evaluate the Co-parental Alliance; the couple’s satisfaction was assessed with the Dyadic Adjustment Scale and the Internalized Homophobia with the MISS-LG. In line with the existent literature, the analysis did not find any difference between lesbian, gay and heterosexual couples in terms of co-parental alliance. High levels of couple adjustment lead to better parental performances among both Italian and Belgian couples. The results suggest also that sexual stigma differs from one country to another, and it has an impact on the capability of managing co-parenting. Clinical implications should be verified in further longitudinal studies in order to observe the impact on the inter-generational transmission of psychopathology. PMID:28261120

  18. Modification of aniline containing proteins using an oxidative coupling strategy.

    Science.gov (United States)

    Hooker, Jacob M; Esser-Kahn, Aaron P; Francis, Matthew B

    2006-12-13

    A new bioconjugation reaction has been developed based on the chemoselective modification of anilines through an oxidative coupling pathway. Aryl amines were installed on the surface of protein substrates through lysine acylation reactions or through the use of native chemical ligation techniques. Upon exposure to NaIO4 in aqueous buffer, the anilines coupled rapidly to the aromatic rings of N,N-dialkyl-N'-acyl-p-phenylenediamines. The identities of the reaction products were confirmed using ESI-MS and through comparison to small molecule analogs. Control experiments indicated that none of the native amino acids participated in the reaction. The resulting bioconjugates were found to be stable toward hydrolysis from pH 4 to pH 11 and in the presence of many commonly used oxidants, reductants, and nucleophiles. A fluorescent phenylenediamine reagent was synthesized for the selective detection of aniline labeled proteins in mixtures, and the reaction was used to append the C-terminus of the green fluorescent protein with a single PEG chain. When combined with techniques for the incorporation of unnatural amino acids into proteins, this bioorthogonal coupling method should prove useful for a number of applications requiring a high degree of labeling specificity.

  19. Calculating luminosity for a coupled Tevatron lattice

    International Nuclear Information System (INIS)

    Holt, J.A.; Martens, M.A.; Michelotti, L.; Goderre, G.

    1995-05-01

    The traditional formula for calculating luminosity assumes an uncoupled lattice and makes use of one-degree-of-freedom lattice functions, β H and β v , for relating transverse beam widths to emittances. Strong coupling requires changing this approach. It is simplest to employ directly the linear normal form coordinates of the one turn map. An equilibrium distribution in phase space is expressed as a function of the Jacobian's eigenvectors and beam size parameters or emittances. Using the equilibrium distributions an expression for the luminosity was derived and applied to the Tevatron lattice, which was coupled due to a quadrupole roll

  20. Generalized Kapchinskij-Vladimirskij Distribution and Envelope Equation for High-intensity Beams in a Coupled Transverse Focusing Lattice

    International Nuclear Information System (INIS)

    Qin, Hong; Chung, Moses; Davidson, Ronald C.

    2009-01-01

    In an uncoupled lattice, the Kapchinskij-Vladimirskij (KV) distribution function first analyzed in 1959 is the only known exact solution of the nonlinear Vlasov-Maxwell equations for high- intensity beams including self-fields in a self-consistent manner. The KV solution is generalized here to high-intensity beams in a coupled transverse lattice using the recently developed generalized Courant-Snyder invariant for coupled transverse dynamics. This solution projects to a rotating, pulsating elliptical beam in transverse configuration space, determined by the generalized matrix envelope equation.

  1. High-Frequency Antenna Arrays and Coupling Structures

    Data.gov (United States)

    National Aeronautics and Space Administration — We are fabricating antenna arrays and coupling structure for frequencies in the 200-300 GHz frequency bands. The primary motivation of this work is to develop...

  2. High-efficiency resonant coupled wireless power transfer via tunable impedance matching

    Science.gov (United States)

    Anowar, Tanbir Ibne; Barman, Surajit Das; Wasif Reza, Ahmed; Kumar, Narendra

    2017-10-01

    For magnetic resonant coupled wireless power transfer (WPT), the axial movement of near-field coupled coils adversely degrades the power transfer efficiency (PTE) of the system and often creates sub-resonance. This paper presents a tunable impedance matching technique based on optimum coupling tuning to enhance the efficiency of resonant coupled WPT system. The optimum power transfer model is analysed from equivalent circuit model via reflected load principle, and the adequate matching are achieved through the optimum tuning of coupling coefficients at both the transmitting and receiving end of the system. Both simulations and experiments are performed to evaluate the theoretical model of the proposed matching technique, and results in a PTE over 80% at close coil proximity without shifting the original resonant frequency. Compared to the fixed coupled WPT, the extracted efficiency shows 15.1% and 19.9% improvements at the centre-to-centre misalignment of 10 and 70 cm, respectively. Applying this technique, the extracted S21 parameter shows more than 10 dB improvements at both strong and weak couplings. Through the developed model, the optimum coupling tuning also significantly improves the performance over matching techniques using frequency tracking and tunable matching circuits.

  3. Holographic gauge mediation via strongly coupled messengers

    International Nuclear Information System (INIS)

    McGuirk, Paul; Shiu, Gary; Sumitomo, Yoske

    2010-01-01

    We consider a relative of semidirect gauge mediation where the hidden sector exists at large 't Hooft coupling. Such scenarios can be difficult to describe using perturbative field theory methods but may fall into the class of holographic gauge mediation scenarios, meaning that they are amenable to the techniques of gauge/gravity duality. We use a recently found gravity solution to examine one such case, where the hidden sector is a cascading gauge theory resulting in a confinement scale not much smaller than the messenger mass. In the original construction of holographic gauge mediation, as in other examples of semidirect gauge mediation at strong coupling, the primary contributions to visible sector soft terms come from weakly coupled messenger mesons. In contrast to these examples, we describe the dual of a gauge theory where there are significant contributions from scales in which the strongly coupled messenger quarks are the effective degrees of freedom. In this regime, the visible sector gaugino mass can be calculated entirely from holography.

  4. Induced alignment and measurement of dipolar couplings of an SH2 domain through direct binding with filamentous phage

    International Nuclear Information System (INIS)

    Dahlke Ojennus, Deanna; Mitton-Fry, Rachel M.; Wuttke, Deborah S.

    1999-01-01

    Large residual 15 N- 1 H dipolar couplings have been measured in a Src homology II domain aligned at Pf1 bacteriophage concentrations an order of magnitude lower than used for induction of a similar degree of alignment of nucleic acids and highly acidic proteins. An increase in 1 H and 15 N protein linewidths and a decrease in T 2 and T 1 ρ relaxation time constants implicates a binding interaction between the protein and phage as the mechanism of alignment. However, the associated increased linewidth does not preclude the accurate measurement of large dipolar couplings in the aligned protein. A good correlation is observed between measured dipolar couplings and predicted values based on the high resolution NMR structure of the SH2 domain. The observation of binding-induced protein alignment promises to broaden the scope of alignment techniques by extending their applicability to proteins that are able to interact weakly with the alignment medium

  5. A comparison of light-coupling into high and low index nanostructured photovoltaic thin films

    Directory of Open Access Journals (Sweden)

    T. Pfadler

    2015-06-01

    Full Text Available Periodically structured electrodes are typically introduced to thin-film photovoltaics for the purpose of light management. Highly effective light-trapping and optimal in-coupling of light is crucial to enhance the overall device performance in such thin-film systems. Here, wavelength-scale structures are transferred via direct laser interference patterning to electron-selective TiO2 electrodes. Two representative thin-film solar cell architectures are deposited on top: an organic solar cell featuring blended P3HT:PCBM as active material, and a hybrid solar cell with Sb2S3 as inorganic active material. A direct correlation in the asymmetry in total absorption enhancement and in structure-induced light in-coupling is spectroscopically observed for the two systems. The structuring is shown to be beneficial for the total absorption enhancement if a high n active material is deposited on TiO2, but detrimental for a low n material. The refractive indices of the employed materials are determined via spectroscopic ellipsometry. The study outlines that the macroscopic Fresnel equations can be used to investigate the spectroscopically observed asymmetry in light in-coupling at the nanostructured TiO2 active material interfaces by visualizing the difference in reflectivity caused by the asymmetry in refractive indices.

  6. Simulation Study of Near-Surface Coupling of Nuclear Devices vs. Equivalent High-Explosive Charges

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, Kevin B [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Walton, Otis R [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Benjamin, Russ [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dunlop, William H [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-09-29

    A computational study was performed to examine the differences in near-surface ground-waves and air-blast waves generated by high-explosive energy sources and those generated by much higher energy - density low - yield nuclear sources. The study examined the effect of explosive-source emplacement (i.e., height-of-burst, HOB, or depth-of-burial, DOB) over a range from depths of -35m to heights of 20m, for explosions with an explosive yield of 1-kt . The chemical explosive was modeled by a JWL equation-of-state model for a ~14m diameter sphere of ANFO (~1,200,000kg – 1 k t equivalent yield ), and the high-energy-density source was modeled as a one tonne (1000 kg) plasma of ‘Iron-gas’ (utilizing LLNL’s tabular equation-of-state database, LEOS) in a 2m diameter sphere, with a total internal-energy content equivalent to 1 k t . A consistent equivalent-yield coupling-factor approach was developed to compare the behavior of the two sources. The results indicate that the equivalent-yield coupling-factor for air-blasts from 1 k t ANFO explosions varies monotonically and continuously from a nearly perfec t reflected wave off of the ground surface for a HOB ≈ 20m, to a coupling factor of nearly zero at DOB ≈ -25m. The nuclear air - blast coupling curve, on the other hand, remained nearly equal to a perfectly reflected wave all the way down to HOB’s very near zero, and then quickly dropped to a value near zero for explosions with a DOB ≈ -10m. The near - surface ground - wave traveling horizontally out from the explosive source region to distances of 100’s of meters exhibited equivalent - yield coupling - factors t hat varied nearly linearly with HOB/DOB for the simulated ANFO explosive source, going from a value near zero at HOB ≈ 5m to nearly one at DOB ≈ -25m. The nuclear-source generated near-surface ground wave coupling-factor remained near zero for almost all HOB’s greater than zero, and then appeared to vary nearly - linearly with depth

  7. Piezoelectricity above the Curie temperature? Combining flexoelectricity and functional grading to enable high-temperature electromechanical coupling

    Energy Technology Data Exchange (ETDEWEB)

    Mbarki, R. [Department of Mechanical Engineering, University of Houston, Houston, Texas 77204 (United States); Baccam, N. [Department of Mathematics, Southwestern University, Georgetown, Texas 78626 (United States); Dayal, Kaushik [Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Sharma, P. [Department of Mechanical Engineering and Department of Physics, University of Houston, Houston, Texas 77204 (United States)

    2014-03-24

    Most technologically relevant ferroelectrics typically lose piezoelectricity above the Curie temperature. This limits their use to relatively low temperatures. In this Letter, exploiting a combination of flexoelectricity and simple functional grading, we propose a strategy for high-temperature electromechanical coupling in a standard thin film configuration. We use continuum modeling to quantitatively demonstrate the possibility of achieving apparent piezoelectric materials with large and temperature-stable electromechanical coupling across a wide temperature range that extends significantly above the Curie temperature. With Barium and Strontium Titanate, as example materials, a significant electromechanical coupling that is potentially temperature-stable up to 900 °C is possible.

  8. Scaling analysis of the coupled heat transfer process in the high-temperature gas-cooled reactor core

    International Nuclear Information System (INIS)

    Conklin, J.C.

    1986-08-01

    The differential equations representing the coupled heat transfer from the solid nuclear core components to the helium in the coolant channels are scaled in terms of representative quantities. This scaling process identifies the relative importance of the various terms of the coupled differential equations. The relative importance of these terms is then used to simplify the numerical solution of the coupled heat transfer for two bounding cases of full-power operation and depressurization from full-system operating pressure for the Fort St. Vrain High-Temperature Gas-Cooled Reactor. This analysis rigorously justifies the simplified system of equations used in the nuclear safety analysis effort at Oak Ridge National Laboratory

  9. The system Cu-Rh-S at 900 degrees, 700 degrees, 540 degrees and 500 degrees C

    DEFF Research Database (Denmark)

    Karup-Møller, Sven; Makovicky, E.

    2007-01-01

    Phase relations in the dry condensed system Cu-Rh-S were determined at 900, 700, 540 and 500 degrees C. At 900 degrees C, the system contains digenite, four rhodium sulfides (Rh17S15, Rh3S4, Rh2S3 and RhS similar to 3), three ternary sulfides (CuRh2S4, CuxRhS3+x and a fibrous sulfide in the range...

  10. Air-Coupled Ultrasonic Receivers with High Electromechanical Coupling PMN-32%PT Strip-Like Piezoelectric Elements

    Directory of Open Access Journals (Sweden)

    Rymantas J. Kazys

    2017-10-01

    Full Text Available For improvement of the efficiency of air-coupled ultrasonic transducers PMN-32%PT piezoelectric crystals which possess very high piezoelectric properties may be used. The electromechanical coupling factor of such crystals for all main vibration modes such as the thickness extension and transverse extension modes is more than 0.9. Operation of ultrasonic transducers with such piezoelectric elements in transmitting and receiving modes is rather different. Therefore, for transmission and reception of ultrasonic signals, separate piezoelectric elements with different dimensions must be used. The objective of this research was development of novel air-coupled ultrasonic receivers with PMN-32%PT strip-like piezoelectric elements vibrating in a transverse-extension mode with electromechanically controlled operation and suitable for applications in ultrasonic arrays. Performance of piezoelectric receivers made of the PMN-32%PT strip-like elements vibrating in this mode may be efficiently controlled by selecting geometry of the electrodes covering side surfaces of the piezoelectric element. It is equivalent to introduction of electromechanical damping which does not require any additional backing element. For this purpose; we have proposed the continuous electrodes to divide into two pairs of electrodes. The one pair is used to pick up the electric signal; another one is exploited for electromechanical damping. Two types of electrodes may be used—rectangular or non-rectangular—with a gap between them directed at some angle, usually 45°. The frequency bandwidth is wider (up to 9 kHz in the case of non-rectangular electrodes. The strip-like acoustic matching element bonded to the tip of the PMN-32%PT crystal may significantly enhance the performance of the ultrasonic receiver. It was proposed to use for this purpose AIREX T10.110 rigid polymer foam, the acoustic impedance of which is close to the optimal value necessary for matching with air. It was

  11. A tri-junction diffusion couple analysis of the Nb-Cr-Ti system at 950{degrees}C

    Energy Technology Data Exchange (ETDEWEB)

    Thoma, D.J. [Los Alamos National Lab., NM (United States); Perepezko, J.H. [Wisconsin Univ., Madison, WI (United States). Dept. of Materials Science and Engineering

    1993-11-01

    With a three-way diffusion couple consisting of a tri-junction between three elements, a whole spectrum of phase development and ternary equilibria is available within a single isothermal sample. Binary equilibria (for the three binary systems) are also available in single sample by analyzing diffusion zones at composition limits outside the field of ternary interaction. The tri-junction approach was employed to evaluate ternary phase formation, ternary solubility limits of binary phases, and diffusion paths in a candidate high-temperature structural system (Nb-Cr-Ti). Ternary phase equilibria and tie lines have been defined at 950C and results confirmed with isothermal anneals of two-phase ternary alloys. The continuous solubility in TiCr{sub 2}-NbCr{sub 2} region is broadened by at least 5 at. % from binary intermetallic phase fields. No new ternary phases were detected in the Nb-CrTi system at 950C. By examining the relative shifts in the diffusion interfaces, a qualitative ranking of interdiffusion suggests that addition of Nb restricts diffusion of Cr into Ti compared to binary (Cr/Ti) behavior.

  12. Purinergic signaling triggers endfoot high-amplitude Ca2+ signals and causes inversion of neurovascular coupling after subarachnoid hemorrhage.

    Science.gov (United States)

    Pappas, Anthony C; Koide, Masayo; Wellman, George C

    2016-11-01

    Neurovascular coupling supports brain metabolism by matching focal increases in neuronal activity with local arteriolar dilation. Previously, we demonstrated that an emergence of spontaneous endfoot high-amplitude Ca 2+ signals (eHACSs) caused a pathologic shift in neurovascular coupling from vasodilation to vasoconstriction in brain slices obtained from subarachnoid hemorrhage model animals. Extracellular purine nucleotides (e.g., ATP) can trigger astrocyte Ca 2+ oscillations and may be elevated following subarachnoid hemorrhage. Here, the role of purinergic signaling in subarachnoid hemorrhage-induced eHACSs and inversion of neurovascular coupling was examined by imaging parenchymal arteriolar diameter and astrocyte Ca 2+ signals in rat brain slices using two-photon fluorescent and infrared-differential interference contrast microscopy. We report that broad-spectrum inhibition of purinergic (P2) receptors using suramin blocked eHACSs and restored vasodilatory neurovascular coupling after subarachnoid hemorrhage. Importantly, eHACSs were also abolished using a cocktail of inhibitors targeting G q -coupled P2Y receptors. Further, activation of P2Y receptors in brain slices from un-operated animals triggered high-amplitude Ca 2+ events resembling eHACSs and disrupted neurovascular coupling. Neither tetrodotoxin nor bafilomycin A1 affected eHACSs suggesting that purine nucleotides are not released by ongoing neurotransmission and/or vesicular release after subarachnoid hemorrhage. These results indicate that purinergic signaling via P2Y receptors contributes to subarachnoid hemorrhage-induced eHACSs and inversion of neurovascular coupling. © The Author(s) 2016.

  13. Protograph LDPC Codes with Node Degrees at Least 3

    Science.gov (United States)

    Divsalar, Dariush; Jones, Christopher

    2006-01-01

    In this paper we present protograph codes with a small number of degree-3 nodes and one high degree node. The iterative decoding threshold for proposed rate 1/2 codes are lower, by about 0.2 dB, than the best known irregular LDPC codes with degree at least 3. The main motivation is to gain linear minimum distance to achieve low error floor. Also to construct rate-compatible protograph-based LDPC codes for fixed block length that simultaneously achieves low iterative decoding threshold and linear minimum distance. We start with a rate 1/2 protograph LDPC code with degree-3 nodes and one high degree node. Higher rate codes are obtained by connecting check nodes with degree-2 non-transmitted nodes. This is equivalent to constraint combining in the protograph. The condition where all constraints are combined corresponds to the highest rate code. This constraint must be connected to nodes of degree at least three for the graph to have linear minimum distance. Thus having node degree at least 3 for rate 1/2 guarantees linear minimum distance property to be preserved for higher rates. Through examples we show that the iterative decoding threshold as low as 0.544 dB can be achieved for small protographs with node degrees at least three. A family of low- to high-rate codes with minimum distance linearly increasing in block size and with capacity-approaching performance thresholds is presented. FPGA simulation results for a few example codes show that the proposed codes perform as predicted.

  14. Effect of various pre-treatments on the ultrafiltration of sweet cheese whey at about 55 degrees C

    Energy Technology Data Exchange (ETDEWEB)

    Hiddink, J; De Boer, R; Nooy, P F.C.

    1981-11-01

    The permeate flux at 55 degrees C during ultrafiltration of Gouda cheese whey (5.5% TS and 11% TS) can be readily manipulated by applying pre-treatments based on inactivation or removal of calcium. The following pre-treatments were carried out: clarification, decalcificication, desalting, pre-heating at 45, 55, and 60 degrees C for 30 minutes, pre-heating at 55 degrees C for 30 minutes combined with pH adjustment to pH 7.5, 4.5 and 3.0 and preheating at 55 degrees C for 30 minutes (coupled with addition of sodum hexametaphosphate. In particular decalification, clarification and pH adjustment to 7.5 or 3.0 gave high permeate fluxes, while pre- heating for 30 minutes resulted in a moderate flux. The pretreatment not only affects the permeate flux but also the composition and properties of the whey protein concentrate. A high ash content, which also reflects a high calcium and phosphorous content, was obtained with a pretreatment based on pH 7 5, while low ash contents were achieved by desalting and clarification. The solubility of the protein was reduced to some 60-70% if the pH of the pre-treated whey was brought to 3.0 or 7.5. Furthermore, it appeared that the influence of the type of membrane - a tubular and a plate-and-frame module were used - was of minor importance as far as the retention or the composition of the whey protein concentrate was concerned. However, the permeate flux of the two types of equipment was different. Under the applied process conditions the tubular system tended to give a higher permeate flux than did the plate-and-frame system, but the energy consumption of the former was considerably higher. (Refs. 25).

  15. [Dynamic coupling and spatial disparity of economic development and water environmental quality in Songhua River Basin of Jilin Province, Northeast China].

    Science.gov (United States)

    Yang, Li-Hua; Tong, Lian-Jun

    2013-02-01

    By using coupling model, this paper analyzed the relationships between the economic development and water environment quality in Songhua River Basin of Jilin Province from 1991 to 2010. During the study period, both the economic development index and the water environment index in the Basin showed an uptrend, basically in a coordination state. From the perspective of coupling coordination degree, the economic development and the water environment system were in interactive coupling, with the features of complexity, nonlinearity, and time-variation. As a whole, the coupling experienced three stages, i.e., low level stage, antagonistic stage, and breaking-in stage. As for the coupling degree, the coupling of the economic development and the water environment system was in the first quadrant, i.e., at a development stage of basic coordination. From the perspective of spatial disparity, the coupling degree of the economic development and the water environment system was higher in the upper reaches of the Songhua River Basin, including Changchun and Jilin, than in the lower reaches, including Songyuan and Baicheng. The coupling degree was not only significantly positively correlated with regional economic development, but also affected by the links between the regions as well as the industrial structure within the regions. The economic development of the cities in the upper reaches of the Songhua River Basin was obviously higher than that in the lower reaches, and, due to the adopting of more strict and effective measures for environmental protection and pollution emissions reduction, the water environment quality in the upper reaches of the Songhua River Basin was better.

  16. When Graduate Degrees Prostitute the Educational Process: Degrees Gone Wild

    Science.gov (United States)

    Lumadue, Richard T.

    2006-01-01

    Graduate degrees prostitute the educational process when they are sold to consumers by unaccredited degree/diploma mills as being equivalent to legitimate, bona-fide degrees awarded by accredited graduate schools. This article carefully analyzes the serious problems of bogus degrees and their association with the religious higher education…

  17. Printed freeform lens arrays on multi-core fibers for highly efficient coupling in astrophotonic systems.

    Science.gov (United States)

    Dietrich, Philipp-Immanuel; Harris, Robert J; Blaicher, Matthias; Corrigan, Mark K; Morris, Tim M; Freude, Wolfgang; Quirrenbach, Andreas; Koos, Christian

    2017-07-24

    Coupling of light into multi-core fibers (MCF) for spatially resolved spectroscopy is of great importance to astronomical instrumentation. To achieve high coupling efficiencies along with fill-fractions close to unity, micro-optical elements are required to concentrate the incoming light to the individual cores of the MCF. In this paper we demonstrate facet-attached lens arrays (LA) fabricated by two-photon polymerization. The LA provide close to 100% fill-fraction along with efficiencies of up to 73% (down to 1.4 dB loss) for coupling of light from free space into an MCF core. We show the viability of the concept for astrophotonic applications by integrating an MCF-LA assembly in an adaptive-optics test bed and by assessing its performance as a tip/tilt sensor.

  18. An investigation of tropical Atlantic bias in a high-resolution coupled regional climate model

    Energy Technology Data Exchange (ETDEWEB)

    Patricola, Christina M.; Saravanan, R.; Hsieh, Jen-Shan [Texas A and M University, Department of Atmospheric Sciences, College Station, TX (United States); Li, Mingkui; Xu, Zhao [Texas A and M University, Department of Oceanography, College Station, TX (United States); Ocean University of China, Key Laboratory of Physical Oceanography of Ministry of Education, Qingdao (China); Chang, Ping [Texas A and M University, Department of Oceanography, College Station, TX (United States); Ocean University of China, Key Laboratory of Physical Oceanography of Ministry of Education, Qingdao (China); Second Institute of Oceanography, State Key Laboratory of Satellite Ocean Environment Dynamics, Hangzhou, Zhejiang (China)

    2012-11-15

    Coupled atmosphere-ocean general circulation models (AOGCMs) commonly fail to simulate the eastern equatorial Atlantic boreal summer cold tongue and produce a westerly equatorial trade wind bias. This tropical Atlantic bias problem is investigated with a high-resolution (27-km atmosphere represented by the Weather Research and Forecasting Model, 9-km ocean represented by the Regional Ocean Modeling System) coupled regional climate model. Uncoupled atmospheric simulations test climate sensitivity to cumulus, land-surface, planetary boundary layer, microphysics, and radiation parameterizations and reveal that the radiation scheme has a pronounced impact in the tropical Atlantic. The CAM radiation simulates a dry precipitation (up to -90%) and cold land-surface temperature (up to -8 K) bias over the Amazon related to an over-representation of low-level clouds and almost basin-wide westerly trade wind bias. The Rapid Radiative Transfer Model and Goddard radiation simulates doubled Amazon and Congo Basin precipitation rates and a weak eastern Atlantic trade wind bias. Season-long high-resolution coupled regional model experiments indicate that the initiation of the warm eastern equatorial Atlantic sea surface temperature (SST) bias is more sensitive to the local rather than basin-wide trade wind bias and to a wet Congo Basin instead of dry Amazon - which differs from AOGCM simulations. Comparisons between coupled and uncoupled simulations suggest a regional Bjerknes feedback confined to the eastern equatorial Atlantic amplifies the initial SST, wind, and deepened thermocline bias, while barrier layer feedbacks are relatively unimportant. The SST bias in some CRCM simulations resembles the typical AOGCM bias indicating that increasing resolution is unlikely a simple solution to this problem. (orig.)

  19. High-{Tc} superconducting antenna-coupled microbolometer on silicon

    Energy Technology Data Exchange (ETDEWEB)

    Rice, J.P.; Grossman, E.N.; Borcherdt, L.J.; Rudman, D.A. [National Inst. of Standards and Technology, Boulder, CO (United States). Cryoelectronic Metrology Group

    1994-12-31

    A process is described for fabricating antenna-coupled resistive-edge microbolometers based on the high-{Tc} superconductor YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO) on silicon. The YBCO and a buffer layer of yttria-stabilized zirconia (YSZ) were grown epitaxially on silicon to minimize excess electrical noise. A silicon-micromachined YBCO/YSZ air-bridge was incorporated to minimize the thermal conductance and the heat capacity. The thermal conductance of the air-bridge was measured to be 3 {times} 10{sup {minus}6} W/K at a temperature of 100 K. At an operating temperature of 89 K, the detector is estimated to have a response time of 2 {micro}s, a responsivity in the 1,000 V/W range, and a noise-equivalent power (NEP) in the 10{sup {minus}12} W/Hz{sup 1/2} range at 1,000 Hz.

  20. Obtaining high-resolution stage forecasts by coupling large-scale hydrologic models with sensor data

    Science.gov (United States)

    Fries, K. J.; Kerkez, B.

    2017-12-01

    We investigate how "big" quantities of distributed sensor data can be coupled with a large-scale hydrologic model, in particular the National Water Model (NWM), to obtain hyper-resolution forecasts. The recent launch of the NWM provides a great example of how growing computational capacity is enabling a new generation of massive hydrologic models. While the NWM spans an unprecedented spatial extent, there remain many questions about how to improve forecast at the street-level, the resolution at which many stakeholders make critical decisions. Further, the NWM runs on supercomputers, so water managers who may have access to their own high-resolution measurements may not readily be able to assimilate them into the model. To that end, we ask the question: how can the advances of the large-scale NWM be coupled with new local observations to enable hyper-resolution hydrologic forecasts? A methodology is proposed whereby the flow forecasts of the NWM are directly mapped to high-resolution stream levels using Dynamical System Identification. We apply the methodology across a sensor network of 182 gages in Iowa. Of these sites, approximately one third have shown to perform well in high-resolution flood forecasting when coupled with the outputs of the NWM. The quality of these forecasts is characterized using Principal Component Analysis and Random Forests to identify where the NWM may benefit from new sources of local observations. We also discuss how this approach can help municipalities identify where they should place low-cost sensors to most benefit from flood forecasts of the NWM.

  1. Interaction of chimera states in a multilayered network of nonlocally coupled oscillators

    Science.gov (United States)

    Goremyko, M. V.; Maksimenko, V. A.; Makarov, V. V.; Ghosh, D.; Bera, B.; Dana, S. K.; Hramov, A. E.

    2017-08-01

    The processes of formation and evolution of chimera states in the model of a multilayered network of nonlinear elements with complex coupling topology are studied. A two-layered network of nonlocally intralayer-coupled Kuramoto-Sakaguchi phase oscillators is taken as the object of investigation. Different modes implemented in this system upon variation of the degree of interlayer interaction are demonstrated.

  2. Plasmonic reflectors and high-Q nano-cavities based on coupled metal-insulator-metal waveguides

    Directory of Open Access Journals (Sweden)

    Jing Chen

    2012-03-01

    Full Text Available Based on the contra-directional coupling, a composite structure consisting of two coupled metal-insulator-metal (MIM waveguides is proposed to act as an attractive plasmonic reflector. By introducing a defect into one of the MIM waveguides, we show that such a composite structure can be operated as a plasmonic nanocavity with a high quality factor. Both symmetric and anti-symmetric cavity modes are supported in the plasmonic cavity, and their resonance frequencies can be tuned by controlling the defect width. The present structures could have a significant impact for potential applications such as surface plasmon mirrors, filters and solid-state cavity quantum electrodynamics.

  3. Two-degrees-of-freedom piezo-driven fast steering mirror with cross-axis decoupling capability

    Science.gov (United States)

    Shao, Shubao; Tian, Zheng; Song, Siyang; Xu, Minglong

    2018-05-01

    Because mechanical cross coupling between its axes would lead to degradation of the scanning precision of a piezo-driven fast steering mirror (PFSM), a two-degrees-of-freedom (2-DoF) PFSM with a cross-axis decoupling capability, in which 2-DoF flexure hinges are used, is proposed in this work. The overall structure of the proposed PFSM is first introduced and then both static and dynamic models are established analytically; in addition, the decoupling mechanism is described in detail and the low dynamic cross coupling ratios that occur between the two DoFs are shown. Because of the decoupling property of the PFSM, the 2-DoF motion is treated as a combination of two independent one-degree-of-freedom (1-DoF) motions and two independent proportional-integral-derivative controllers are thus used separately in the control of the two DoFs. Based on this control strategy, experiments involving both 1-DoF trajectory tracking and 2-DoF trajectory tracking are implemented. The test results show that the proposed PFSM can achieve the tilt range of ±7 mrad for both axes with the low coupling ratios that are less than 2% (-34 dB), and the bandwidths of both axes are higher than 810 Hz; in addition, the maximal tracking full scale range errors for 1-DoF trajectory tracking and 2-DoF trajectory tracking are less than 0.2% and 1%, respectively, where the larger error of 2-DoF trajectory tracking is mainly caused by the remaining cross coupling between axes.

  4. a Study of Vibrational Mode Coupling in 2-FLUOROETHANOL and 1,2-DIFLUOROETHANE Using High-Resolution Infrared Spectroscopy.

    Science.gov (United States)

    Mork, Steven Wayne

    High resolution infrared spectroscopy was used to examine intramolecular vibrational interactions in 2 -fluoroethanol (2FE) and 1,2-difluoroethane (DFE). A high resolution infrared spectrophotometer capable of better than 10 MHz spectral resolution was designed and constructed. The excitation source consists of three lasers: an argon-ion pumped dye laser which pumps a color -center laser. The infrared beam from the color-center laser is used to excite sample molecules which are rotationally and vibrationally cooled in a supersonic molecular beam. Rovibrational excitation of the sample molecules is detected by monitoring the kinetic energy of the molecular beam with a bolometer. The high resolution infrared spectrum of 2FE was collected and analyzed over the 2977-2990 cm^ {-1}^ectral region. This region contains the asymmetric CH stretch on the fluorinated carbon. The spectrum revealed extensive perturbations in the rotational fine structure. Analysis of these perturbations has provided a quantitative measure of selective vibrational mode coupling between the C-H stretch and its many neighboring dark vibrational modes. Interestingly, excitation of the C-H stretch is known to induce a photoisomerization reaction between 2FE's Gg^' and Tt conformers. Implications of the role of mode coupling in the reaction mechanism are also addressed. Similarly, the high resolution infrared spectrum of DFE was collected and analyzed over the 2978-2996 cm ^{-1}^ectral region. This region contains the symmetric combination of asymmetric C-H stretches in DFE. Perturbations in the rotational fine structure indicate vibrational mode coupling to a single dark vibrational state. The dark state is split by approximately 19 cm^{-1} due to tunneling between two identical gauche conformers. The coupling mechanism is largely anharmonic with a minor component of B/C-plane Coriolis coupling. Effects of centrifugal distortion along the molecular A-axis are also observed. The coupled vibrational

  5. The influence of single neuron dynamics and network topology on time delay-induced multiple synchronous behaviors in inhibitory coupled network

    International Nuclear Information System (INIS)

    Zhao, Zhiguo; Gu, Huaguang

    2015-01-01

    Highlights: • Time delay-induced multiple synchronous behaviors was simulated in neuronal networks. • Multiple behaviors appear at time delays shorter than a bursting period of neurons. • The more spikes per burst of bursting, the more synchronous regions of time delay. • From regular to random via small-world networks, synchronous degree becomes weak. • An interpretation of the multiple behaviors and the influence of network are provided. - Abstract: Time delay induced-multiple synchronous behaviors are simulated in neuronal network composed of many inhibitory neurons and appear at different time delays shorter than a period of endogenous bursting of individual neurons. It is different from previous investigations wherein only one of multiple synchronous behaviors appears at time delay shorter than a period of endogenous firing and others appear at time delay longer than the period duration. The bursting patterns of the synchronous behaviors are identified based on the dynamics of an individual neuron stimulated by a signal similar to the inhibitory coupling current, which is applied at the decaying branch of a spike and suitable phase within the quiescent state of the endogenous bursting. If a burst of endogenous bursting contains more spikes, the synchronous behaviors appear at more regions of time delay. As the coupling strength increases, the multiple synchronous behaviors appear in a sequence because the different threshold of coupling current or strength is needed to achieve synchronous behaviors. From regular, to small-world, and to random networks, synchronous degree of the multiple synchronous behaviors becomes weak, and synchronous bursting patterns with lower spikes per burst disappear, which is properly interpreted by the difference of coupling current between neurons induced by different degree and the high threshold of coupling current to achieve synchronization for the absent synchronous bursting patterns. The results of the influence of

  6. Electromagnetic clutches and couplings

    CERN Document Server

    Vorob'Yeva, T M; Fry, D W; Higinbotham, W

    2013-01-01

    Electromagnetic Clutches and Couplings contains a detailed description of U.S.S.R. electromagnetic friction clutches, magnetic couplings, and magnetic particle couplings. This book is divided into four chapters. The first chapter discusses the design and construction of magnetic (solenoid-operated) couplings, which are very quick-acting devices and used in low power high-speed servo-systems. Chapter 2 describes the possible fields of application, design, construction, and utilization of magnetic particle couplings. The aspects of construction, design, and utilization of induction clutches (sli

  7. Determination of trimethyllead reference material using high performance liquid chromatography-inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Lu Hai; Wei Chao; Wang Jun; Chao Jingbo; Zhou Tao; Chen Dazhou

    2005-01-01

    A high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) was combined, and the chromatography conditions were optimized. The stability and homogeneity of a trimethyllead reference material were determined using this method. (authors)

  8. Fano resonances in a high-Q terahertz whispering-gallery mode resonator coupled to a multi-mode waveguide.

    Science.gov (United States)

    Vogt, Dominik Walter; Leonhardt, Rainer

    2017-11-01

    We report on Fano resonances in a high-quality (Q) whispering-gallery mode (WGM) spherical resonator coupled to a multi-mode waveguide in the terahertz (THz) frequency range. The asymmetric line shape and phase of the Fano resonances detected with coherent continuous-wave (CW) THz spectroscopy measurements are in excellent agreement with the analytical model. A very high Q factor of 1600, and a finesse of 22 at critical coupling is observed around 0.35 THz. To the best of our knowledge this is the highest Q factor ever reported for a THz WGM resonator.

  9. Dual frequency parametric excitation of a nonlinear, multi degree of freedom mechanical amplifier with electronically modified topology

    Science.gov (United States)

    Dolev, A.; Bucher, I.

    2018-04-01

    Mechanical or electromechanical amplifiers can exploit the high-Q and low noise features of mechanical resonance, in particular when parametric excitation is employed. Multi-frequency parametric excitation introduces tunability and is able to project weak input signals on a selected resonance. The present paper addresses multi degree of freedom mechanical amplifiers or resonators whose analysis and features require treatment of the spatial as well as temporal behavior. In some cases, virtual electronic coupling can alter the given topology of the resonator to better amplify specific inputs. An analytical development is followed by a numerical and experimental sensitivity and performance verifications, illustrating the advantages and disadvantages of such topologies.

  10. Triple degree-of-freedom piezoelectric ultrasonic micromotor via flexural-axial coupled vibration.

    Science.gov (United States)

    Khoo, Ter Fong; Dang, Dinh Huy; Friend, James; Oetomo, Denny; Yeo, Leslie

    2009-08-01

    Actuators remain a limiting factor in robotics, especially in microrobotics where the power density of actuators is a problem. A 3 x 3 x 8.7 mm 3-axis piezoelectric ultrasonic micromotor system is described here in an effort to help solve this problem. Formed from 4 bulk lead zirconate titanate (PZT) thickness-polarized elements placed around the periphery of a rectangular rod, the stator is designed to combine axial and flexural vibrations in a way that permits rotation of a hardened steel ball as a rotor about an arbitrary axis. A simple prototype of the micromotor was found to produce at least a rotation speed of 10.4 rad/s with 4 microN-m torque about all 3 orthogonal directions at an excitation frequency of about 221 kHz, demonstrating the feasibility of a 3 degree-of-freedom millimeter-scale piezoelectric motor.

  11. Second-degree discrete Painleve equations conceal first-degree ones

    International Nuclear Information System (INIS)

    Ramani, A; Grammaticos, B; Joshi, N

    2010-01-01

    We examine various second-degree difference equations which have been proposed over the years and according to their authors' claims should be integrable. This study is motivated by the fact that we consider that second-degree discrete systems cannot be integrable due to the proliferation of the images (and pre-images) of the initial point. We show that in the present cases no contradiction exists. In all cases examined, we show that there exists an underlying integrable first-degree mapping which allows us to obtain an appropriate solution of the second-degree one.

  12. Cervical Coupling Motion Characteristics in Healthy People Using a Wireless Inertial Measurement Unit

    Directory of Open Access Journals (Sweden)

    Hyunho Kim

    2013-01-01

    Full Text Available Objective. The objectives were to show the feasibility of a wireless microelectromechanical system inertial measurement unit (MEMS-IMU to assess the time-domain characteristics of cervical motion that are clinically useful to evaluate cervical spine movement. Methods. Cervical spine movements were measured in 18 subjects with wireless IMUs. All rotation data are presented in the Euler angle system. Amount of coupling motions was evaluated by calculating the average angle ratio and the maximum angle ratio of the coupling motion to the primary motion. Reliability is presented with intraclass correlation coefficients (ICC. Results. Entire time-domain characteristics of cervical motion were measured with developed MEMS-IMU system. Cervical range of motion (CROM and coupling motion range were measured with high ICCs. The acquired data and calculated parameters had similar tendency with the previous studies. Conclusions. We evaluated cervical motion with economic system using a wireless IMU of high reliability. We could directly measure the three-dimensional cervical motion in degrees in realtime. The characteristics measured by this system may provide a diagnostic basis for structural or functional dysfunction of cervical spine. This system is also useful to demonstrate the effectiveness of any intervention such as conventional medical treatment, and Korean medical treatment, exercise therapy.

  13. Degree of synchronization modulated by inhibitory neurons in clustered excitatory-inhibitory recurrent networks

    Science.gov (United States)

    Li, Huiyan; Sun, Xiaojuan; Xiao, Jinghua

    2018-01-01

    An excitatory-inhibitory recurrent neuronal network is established to numerically study the effect of inhibitory neurons on the synchronization degree of neuronal systems. The obtained results show that, with the number of inhibitory neurons and the coupling strength from an inhibitory neuron to an excitatory neuron increasing, inhibitory neurons can not only reduce the synchronization degree when the synchronization degree of the excitatory population is initially higher, but also enhance it when it is initially lower. Meanwhile, inhibitory neurons could also help the neuronal networks to maintain moderate synchronized states. In this paper, we call this effect as modulation effect of inhibitory neurons. With the obtained results, it is further revealed that the ratio of excitatory neurons to inhibitory neurons being nearly 4 : 1 is an economic and affordable choice for inhibitory neurons to realize this modulation effect.

  14. Dynamics and manipulation of entanglement in coupled harmonic systems with many degrees of freedom

    Science.gov (United States)

    Plenio, M. B.; Hartley, J.; Eisert, J.

    2004-03-01

    We study the entanglement dynamics of a system consisting of a large number of coupled harmonic oscillators in various configurations and for different types of nearest-neighbour interactions. For a one-dimensional chain, we provide compact analytical solutions and approximations to the dynamical evolution of the entanglement between spatially separated oscillators. Key properties such as the speed of entanglement propagation, the maximum amount of transferred entanglement and the efficiency for the entanglement transfer are computed. For harmonic oscillators coupled by springs, corresponding to a phonon model, we observe a non-monotonic transfer efficiency in the initially prepared amount of entanglement, i.e. an intermediate amount of initial entanglement is transferred with the highest efficiency. In contrast, within the framework of the rotating-wave approximation (as appropriate, e.g. in quantum optical settings) one finds a monotonic behaviour. We also study geometrical configurations that are analogous to quantum optical devices (such as beamsplitters and interferometers) and observe characteristic differences when initially thermal or squeezed states are entering these devices. We show that these devices may be switched on and off by changing the properties of an individual oscillator. They may therefore be used as building blocks of large fixed and pre-fabricated but programmable structures in which quantum information is manipulated through propagation. We discuss briefly possible experimental realizations of systems of interacting harmonic oscillators in which these effects may be confirmed experimentally.

  15. The networks scale and coupling parameter in synchronization of neural networks with diluted synapses

    International Nuclear Information System (INIS)

    Li Yanlong; Ma Jun; Chen Yuhong; Xu Wenke; Wang Yinghai

    2008-01-01

    In this paper the influence of the networks scale on the coupling parameter in the synchronization of neural networks with diluted synapses is investigated. Using numerical simulations, an exponential decay form is observed in the extreme case of global coupling among networks and full connection in each network; the larger linked degree becomes, the larger critical coupling intensity becomes; and the oscillation phenomena in the relationship of critical coupling intensity and the number of neural networks layers in the case of small-scale networks are found

  16. Synchronization and chaos in spin-transfer-torque nano-oscillators coupled via a high-speed operational amplifier

    International Nuclear Information System (INIS)

    Sanid, C; Murugesh, S

    2014-01-01

    We propose a system of two coupled spin-torque nano-oscillators (STNOs), one driver and another response, and demonstrate using numerical studies the synchronization of the response system to the frequency of the driver system. To this end we use a high-speed operational amplifier in the form of a voltage follower, which essentially isolates the drive system from the response system. We find the occurrence of 1 : 1 as well as 2 : 1 synchronization in the system, wherein the oscillators show limit cycle dynamics. An increase in power output is noticed when the two oscillators are locked in 1 : 1 synchronization. Moreover in the crossover region between these two synchronization dynamics we show the existence of chaotic dynamics in the slave system. The coupled dynamics under periodic forcing, using a small ac input current in addition to that of the dc part, is also studied. The slave oscillator is seen to retain its qualitative identity in the parameter space in spite of being fed in, at times, a chaotic signal. Such electrically coupled STNOs will be highly useful in fabricating commercial spin-valve oscillators with high power output, when integrated with other spintronic devices. (paper)

  17. Exact sampling of graphs with prescribed degree correlations

    Science.gov (United States)

    Bassler, Kevin E.; Del Genio, Charo I.; Erdős, Péter L.; Miklós, István; Toroczkai, Zoltán

    2015-08-01

    Many real-world networks exhibit correlations between the node degrees. For instance, in social networks nodes tend to connect to nodes of similar degree and conversely, in biological and technological networks, high-degree nodes tend to be linked with low-degree nodes. Degree correlations also affect the dynamics of processes supported by a network structure, such as the spread of opinions or epidemics. The proper modelling of these systems, i.e., without uncontrolled biases, requires the sampling of networks with a specified set of constraints. We present a solution to the sampling problem when the constraints imposed are the degree correlations. In particular, we develop an exact method to construct and sample graphs with a specified joint-degree matrix, which is a matrix providing the number of edges between all the sets of nodes of a given degree, for all degrees, thus completely specifying all pairwise degree correlations, and additionally, the degree sequence itself. Our algorithm always produces independent samples without backtracking. The complexity of the graph construction algorithm is {O}({NM}) where N is the number of nodes and M is the number of edges.

  18. Study on Earthquake Response of High Voltage Electrical Equipment Coupling System with Flexible Busbar

    Science.gov (United States)

    Liu, Chuncheng; Qu, Da; Wang, Chongyang; Lv, Chunlei; Li, Guoqiang

    2017-12-01

    With the rapid development of technology and society, all walks of life in China are becoming more and more dependent on power systems. When earthquake occurs, the electrical equipment of substation is prone to damage because of its own structural features, top-heavy, and brittleness of main body. At the same time, due to the complex coupling of the soft electrical connection of substation electrical equipment, the negative impact can not be estimated. In this paper, the finite element model of the coupling system of the single unit of high voltage electrical equipment with the connecting soft bus is established and the seismic response is analysed. The results showed that there is a significant difference between the simple analysis for the seismic response of electrical equipment monomer and the analytical results of electrical equipment systems, and the impact on different electrical equipment is different. It lays a foundation for the future development of seismic performance analysis of extra high voltage electrical equipment.

  19. Analysis method of high-order collective-flow correlations based on the concept of correlative degree

    International Nuclear Information System (INIS)

    Zhang Weigang

    2000-01-01

    Based on the concept of correlative degree, a new method of high-order collective-flow measurement is constructed, with which azimuthal correlations, correlations of final state transverse momentum magnitude and transverse correlations can be inspected respectively. Using the new method the contributions of the azimuthal correlations of particles distribution and the correlations of transverse momentum magnitude of final state particles to high-order collective-flow correlations are analyzed respectively with 4π experimental events for 1.2 A GeV Ar + BaI 2 collisions at the Bevalac stream chamber. Comparing with the correlations of transverse momentum magnitude, the azimuthal correlations of final state particles distribution dominate high-order collective-flow correlations in experimental samples. The contributions of correlations of transverse momentum magnitude of final state particles not only enhance the strength of the high-order correlations of particle group, but also provide important information for the measurement of the collectivity of collective flow within the more constraint district

  20. {sup 252}Cf spontaneous prompt fission neutron spectrum measured at 0 degree and 180 degree relative to the fragment motion

    Energy Technology Data Exchange (ETDEWEB)

    Shanglian, Bao; Jinquan, Liu [Beijing Univ., BJ (China); Batenkov, O I; Blinov, M V; Smirnov, S N [V.G. Khlopin Radium Institute, ST. Petersburg (Russian Federation)

    1994-09-01

    The {sup 252}Cf spontaneous prompt fission neutron spectrum at 0 degree and 180 degree relative to the motion direction of corresponding fission fragments was measured. High angular resolution for fragment measurements and high energy resolution for neutron measurements were obtained using multi-parameter TOF spectrometer. The results showed that there is a symmetric distribution of `forward` and `backward` for low energy in C.M.S. neutrons, which was an evidence of nonequilibrium neutrons existed in fission process.

  1. Modeling Coupled THMC Processes and Brine Migration in Salt at High Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, Jonny; Blanco Martin, Laura; Mukhopadhyay, Sumit; Houseworth, Jim; Birkholzer, Jens

    2014-08-14

    In this report, we present FY2014 progress by Lawrence Berkeley National Laboratory (LBNL) related to modeling of coupled thermal-hydrological-mechanical-chemical (THMC) processes in salt and their effect on brine migration at high temperatures. LBNL’s work on the modeling of coupled THMC processes in salt was initiated in FY2012, focusing on exploring and demonstrating the capabilities of an existing LBNL modeling tool (TOUGH-FLAC) for simulating temperature-driven coupled flow and geomechanical processes in salt. This work includes development related to, and implementation of, essential capabilities, as well as testing the model against relevant information and published experimental data related to the fate and transport of water. we provide more details on the FY2014 work, first presenting updated tools and improvements made to the TOUGH-FLAC simulator, and the use of this updated tool in a new model simulation of long-term THM behavior within a generic repository in a salt formation. This is followed by the description of current benchmarking and validations efforts, including the TSDE experiment. We then present the current status in the development of constitutive relationships and the dual-continuum model for brine migration. We conclude with an outlook for FY2015, which will be much focused on model validation against field experiments and on the use of the model for the design studies related to a proposed heater experiment.

  2. Research and analysis on response characteristics of bracket-line coupling system under wind load

    Science.gov (United States)

    Jiayu, Zhao; Qing, Sun

    2018-01-01

    In this paper, a three-dimensional finite element model of bracket-line coupling system is established based on ANSYS software. Using the wind velocity time series which is generated by MATLAB as a power input, by comparing and analyzing the influence of different wind speeds and different wind attack angles, it is found that when 0 degree wind acts on the structure, wires have a certain damping effect in the bracket-line coupling system and at the same wind speed, the 90 degree direction is the most unfavorable wind direction for the whole structure according to the three kinds of angle wind calculated at present. In the bracket-line coupling system, the bracket structure is more sensitive to the increase of wind speed while the conductors are more sensitive to the change of wind attack angle.

  3. Contagion processes on the static and activity-driven coupling networks

    Science.gov (United States)

    Lei, Yanjun; Jiang, Xin; Guo, Quantong; Ma, Yifang; Li, Meng; Zheng, Zhiming

    2016-03-01

    The evolution of network structure and the spreading of epidemic are common coexistent dynamical processes. In most cases, network structure is treated as either static or time-varying, supposing the whole network is observed in the same time window. In this paper, we consider the epidemics spreading on a network which has both static and time-varying structures. Meanwhile, the time-varying part and the epidemic spreading are supposed to be of the same time scale. We introduce a static and activity-driven coupling (SADC) network model to characterize the coupling between the static ("strong") structure and the dynamic ("weak") structure. Epidemic thresholds of the SIS and SIR models are studied using the SADC model both analytically and numerically under various coupling strategies, where the strong structure is of homogeneous or heterogeneous degree distribution. Theoretical thresholds obtained from the SADC model can both recover and generalize the classical results in static and time-varying networks. It is demonstrated that a weak structure might make the epidemic threshold low in homogeneous networks but high in heterogeneous cases. Furthermore, we show that the weak structure has a substantive effect on the outbreak of the epidemics. This result might be useful in designing some efficient control strategies for epidemics spreading in networks.

  4. High speed gain coupled DFB laser diode integrated with MQW electroabsorption modulator

    International Nuclear Information System (INIS)

    Kim, Myung Gyoo; Lee, Seung Won; Park, Seong Su; Oh, Dae Kon; Lee, Hee Tae; Kim, Hong man; Pyun, Kwang Eui

    1998-01-01

    We have demonstrated stable modulation characteristics of the gain coupled distributed feedback(GC-DFB) laser diode integrated with butt-coupled InGaAsP/InGaAsP strain compensated MQW(multiple-Quantum-well) modulator for high speed optical transmission. For this purpose, we have adopted the InGaAsP/InGaAsP strain compensated MQW structure for the EA modulator and n-doped InGaAs absorptive grating for DFB laser. The typical threshold current and slope efficiency were about 15 mA and 0.1 mW/mA, respectively. The extinction ratio of fabricated integrated device was about 15 dB at -2 V, and the small signal bandwidth was shown to be around 17GHz. We also found that the α parameter becomes negative at below a -0.6 V bias voltage. We transmitted 10 Gbps NRZ electrical signal over 90 km of standard single mode optical fiber (SMF). A clearly opened eye diagram was observed in the modulated output

  5. High speed gain coupled DFB laser diode integrated with MQW electroabsorption modulator

    CERN Document Server

    Kim, M G; Park, S S; Oh, D K; Lee, H T; Kim, H M; Pyun, K E

    1998-01-01

    We have demonstrated stable modulation characteristics of the gain coupled distributed feedback(GC-DFB) laser diode integrated with butt-coupled InGaAsP/InGaAsP strain compensated MQW(multiple-Quantum-well) modulator for high speed optical transmission. For this purpose, we have adopted the InGaAsP/InGaAsP strain compensated MQW structure for the EA modulator and n-doped InGaAs absorptive grating for DFB laser. The typical threshold current and slope efficiency were about 15 mA and 0.1 mW/mA, respectively. The extinction ratio of fabricated integrated device was about 15 dB at -2 V, and the small signal bandwidth was shown to be around 17GHz. We also found that the alpha parameter becomes negative at below a -0.6 V bias voltage. We transmitted 10 Gbps NRZ electrical signal over 90 km of standard single mode optical fiber (SMF). A clearly opened eye diagram was observed in the modulated output.

  6. High coupling performance of JT-60U ICRF antennas

    International Nuclear Information System (INIS)

    Saigusa, M.; Moriyama, S.; Fujii, T.; Kimura, H.; Sato, M.; Hosogane, N.; Nemoto, M.; Yamamoto, T.

    1994-01-01

    Sufficient coupling of an ICRF antenna for high power experiments was obtained even for a wide gap between the separatrix and the antenna in JT-60U. The loading resistances for an out-of-phase mode are over 4 Ω for a gap of 13 cm between the separatrix and the Faraday shield over the wide range of electron density from 1 x 10 19 to 5.5 x 10 19 m -3 . In particular, the loading resistances for an in-phase mode are about 5 Ω for a gap of 33 cm between the separatrix and the Faraday shield for the same plasma parameters. However, the heating response for the out-of phase mode is much stronger than that for the in-phase mode. (author). Letter-to-the-editor. 11 refs, 6 figs

  7. High-capacity quantum key distribution via hyperentangled degrees of freedom

    International Nuclear Information System (INIS)

    Simon, David S; Sergienko, Alexander V

    2014-01-01

    Quantum key distribution (QKD) has long been a promising area for the application of quantum effects in solving real-world problems. However, two major obstacles have stood in the way of its widespread application: low secure key generation rates and short achievable operating distances. In this paper, a new physical mechanism for dealing with the first of these problems is proposed: the interplay between different degrees of freedom in a hyperentangled system (parametric down-conversion) is used to increase the Hilbert space dimension available for key generation while maintaining security. Polarization-based Bell tests provide security checking, while orbital angular momentum (OAM) and total angular momentum (TAM) provide a higher key generation rate. Whether to measure TAM or OAM is decided randomly in each trial. The concurrent noncommutativity of TAM with OAM and polarization provides the physical basis for quantum security. TAM measurements link polarization to OAM, so that if the legitimate participants measure OAM while the eavesdropper measures TAM (or vice-versa), then polarization entanglement is lost, revealing the eavesdropper. In contrast to other OAM-based QKD methods, complex active switching between OAM bases is not required; instead, passive switching by beam splitters combined with much simpler active switching between polarization bases makes implementation at high OAM more practical. (paper)

  8. Polymorphic Nature of Iron and Degree of Lattice Preferred Orientation Beneath the Earth's Inner Core Boundary

    Science.gov (United States)

    Mattesini, Maurizio; Belonoshko, Anatoly B.; Tkalčić, Hrvoje

    2018-01-01

    Deciphering the polymorphic nature and the degree of iron lattice-preferred orientation in the Earth's inner core holds a key to understanding the present status and evolution of the inner core. A multiphase lattice-preferred orientation pattern is obtained for the top 350 km of the inner core by means of the ab initio based Candy Wrapper Velocity Model coupled to a Monte Carlo phase discrimination scheme. The achieved geographic distribution of lattice alignment is characterized by two regions of freezing, namely within South America and the Western Central Pacific, that exhibit an uncommon high degree of lattice orientation. In contrast, widespread regions of melting of relatively weak lattice ordering permeate the rest of the inner core. The obtained multiphase lattice-preferred orientation pattern is in line with mantle-constrained geodynamo simulations and allows to setup an ad hoc mineral physics scenario for the complex Earth's inner core. It is found that the cubic phase of iron is the dominating iron polymorph in the outermost part of the inner core.

  9. Extraction of surface plasmons in organic light-emitting diodes via high-index coupling.

    Science.gov (United States)

    Scholz, Bert J; Frischeisen, Jörg; Jaeger, Arndt; Setz, Daniel S; Reusch, Thilo C G; Brütting, Wolfgang

    2012-03-12

    The efficiency of organic light-emitting diodes (OLEDs) is still limited by poor light outcoupling. In particular, the excitation of surface plasmon polaritons (SPPs) at metal-organic interfaces represents a major loss channel. By combining optical simulations and experiments on simplified luminescent thin-film structures we elaborate the conditions for the extraction of SPPs via coupling to high-index media. As a proof-of-concept, we demonstrate the possibility to extract light from wave-guided modes and surface plasmons in a top-emitting white OLED by a high-index prism.

  10. NEW CONCEPTUAL SOLUTIONS FOR ELASTIC COUPLINGS WITH HIGH CAPABILITY COMPENSATION OF MISALIGNMENTS

    Directory of Open Access Journals (Sweden)

    DOBRE Daniel

    2015-06-01

    Full Text Available The paper develops a problem of great interest in power transmissions, very widely applied in practice: the use of elastic couplings having an adequate level of torque transmission and a reasonable axial and angular misalignment capability based on elastic deformations of specific flexible elements. A characterization (discussion of two elastic couplings characteristic for the area of compensative couplings is offered. An innovative principle of elastic coupling with reinforced flexible elements is proposed. The mechanical strength analysis for both elastic couplings (with spoked metallic membranes and reinforced elastic elements in the case of existing axial and angular deviations is discussed also. It is revealed that the study of these couplings based on elastic deformations is of great theoretical and practical importance today.

  11. Relationship between birth order of spouses with different degrees of consanguineous relationship.

    Science.gov (United States)

    Reddy, B M; Malhotra, K C

    1991-08-01

    The relationship between birth order of spouses with different degrees of consanguinity is examined in a sample of 1826 couples belonging to the endogamous Vadde Fisherfolk of Kolleru Lake, Andhra Pradesh, India. We attempt to explain the wide variation in the frequency of different kinds of consanguineous marriages through the age-sex structure of the population in general and especially of the related families. This structure may also be manifested in the association between the birth orders of spouses. A highly significant and large correlation between the birth orders of spouses in uncle-niece marriages and a gradual decrease in the correlation with increase in remoteness of the relationship between the spouses were observed. Given the distribution of age differences between the spouses and assuming a standard age-sex structure, it seems possible to estimate the optimum frequency with which at least close consanguineous marriages occur in any particular population.

  12. A MATLAB-based graphical user interface program for computing functionals of the geopotential up to ultra-high degrees and orders

    Science.gov (United States)

    Bucha, Blažej; Janák, Juraj

    2013-07-01

    We present a novel graphical user interface program GrafLab (GRAvity Field LABoratory) for spherical harmonic synthesis (SHS) created in MATLAB®. This program allows to comfortably compute 38 various functionals of the geopotential up to ultra-high degrees and orders of spherical harmonic expansion. For the most difficult part of the SHS, namely the evaluation of the fully normalized associated Legendre functions (fnALFs), we used three different approaches according to required maximum degree: (i) the standard forward column method (up to maximum degree 1800, in some cases up to degree 2190); (ii) the modified forward column method combined with Horner's scheme (up to maximum degree 2700); (iii) the extended-range arithmetic (up to an arbitrary maximum degree). For the maximum degree 2190, the SHS with fnALFs evaluated using the extended-range arithmetic approach takes only approximately 2-3 times longer than its standard arithmetic counterpart, i.e. the standard forward column method. In the GrafLab, the functionals of the geopotential can be evaluated on a regular grid or point-wise, while the input coordinates can either be read from a data file or entered manually. For the computation on a regular grid we decided to apply the lumped coefficients approach due to significant time-efficiency of this method. Furthermore, if a full variance-covariances matrix of spherical harmonic coefficients is available, it is possible to compute the commission errors of the functionals. When computing on a regular grid, the output functionals or their commission errors may be depicted on a map using automatically selected cartographic projection.

  13. Generation of high-fidelity controlled-NOT logic gates by coupled superconducting qubits

    International Nuclear Information System (INIS)

    Galiautdinov, Andrei

    2007-01-01

    Building on the previous results of the Weyl chamber steering method, we demonstrate how to generate high-fidelity controlled-NOT (CNOT) gates by direct application of certain physically relevant Hamiltonians with fixed coupling constants containing Rabi terms. Such Hamiltonians are often used to describe two superconducting qubits driven by local rf pulses. It is found that in order to achieve 100% fidelity in a system with capacitive coupling of strength g, one Rabi term suffices. We give the exact values of the physical parameters needed to implement such CNOT gates. The gate time and all possible Rabi frequencies are found to be t=π/(2g) and Ω 1 /g=√(64n 2 -1),n=1,2,3,.... Generation of a perfect CNOT gate in a system with inductive coupling, characterized by additional constant k, requires the presence of both Rabi terms. The gate time is again t=π/(2g), but now there is an infinite number of solutions, each of which is valid in a certain range of k and is characterized by a pair of integers (n,m), (Ω 1,2 /g)=√(16n 2 -((k-1/2)) 2 )±√(16m 2 -((k+1/2)) 2 ). We distinguish two cases, depending on the sign of the coupling constant: (i) the antiferromagnetic case (k≥0) with n≥m=0,1,2,... and (ii) the ferromagnetic case (k≤0) with n>m=0,1,2,.... We conclude with consideration of fidelity degradation by switching to resonance. Simulation of time evolution based on the fourth-order Magnus expansion reveals characteristics of the gate similar to those found in the exact case, with slightly shorter gate time and shifted values of the Rabi frequencies

  14. Comparing Brain Behavioral Systems in Couples Engaged in Infidelity and Normal Couples in Tabriz, Tehran and Karaj

    Directory of Open Access Journals (Sweden)

    Alireza Karimpour Vazifehkhorani

    2017-10-01

    Full Text Available Background and Objectives: This study aimed to compare Gary Behavioral Systems (behavioral activation system and behavioral inhibition system in normal couples and those engaged in marital infidelity. Material and Methods: The research was descriptive and causal-comparative. Study population consisted of normal couples and couples who were betrayed in the cities of Tehran, Karaj and Tabriz that were referred to counseling clinics. Study sample consisted of 100 clients; 50 normal couples and 50 couples who were involved in marital infidelity. Sampling was targeted. To collect data, Grey-Wilson's and wife infidelity questionnaires were used. Results: Inhibition of behavior in normal couples was higher than couples involved in marital infidelity which was significant at P Conclusion: Couples who have activation system of high sensitivity are more involved in the phenomenon of marital infidelity compared to the couples who are at high behavioral inhibition system.

  15. Safety Philosophy in Process Heat Plants Coupled to High Temperature Reactors

    International Nuclear Information System (INIS)

    Brown, Nicholas R.; Revankar, Shripad T.

    2011-01-01

    With the future availability of fossil fuel resources in doubt, high temperature nuclear reactors have the potential to be an important technology in the near term. Due to a high coolant outlet temperature, high temperature reactors (HTR) can be used to drive chemical plants that directly utilize process heat. Additionally, the high temperature improves the thermodynamic efficiency of the energy utilization. Many applications of high temperature reactors exist as a thermal driving vector for endothermic chemical process plants. Hydrogen generation using the General Atomics (GA) sulfur iodine (SI) cycle is one promising application of high temperature nuclear heat. The main chemical reactions in the SI cycle are: 1. I 2 +SO 2 + 2H 2 O → 2HI + H 2 SO 4 (Bunsen reaction) 2. H 2 SO 4 → H 2 O + SO 2 + 1/2O 2 (Sulfuric acid decomposition) 3. 2HI → H 2 + I 2 (Hydrogen Iodide decomposition). With the exception of hydrogen and oxygen, all relevant reactants are recycled within the process. However, there are many unresolved safety and operational issues related to implementation of such a coupled plant

  16. Reflux and Belching After 270 Degree Versus 360 Degree Laparoscopic Posterior Fundoplication

    NARCIS (Netherlands)

    Broeders, Joris A.; Bredenoord, Albert J.; Hazebroek, Eric J.; Broeders, Ivo A.; Gooszen, Hein G.; Smout, André J.

    2012-01-01

    Objective: To investigate differences in effects of 270 degrees (270 degrees LPF) and 360 degrees laparoscopic posterior fundoplication (360 degrees LPF) on reflux characteristics and belching. Background: Three hundred sixty degrees LPF greatly reduces the ability of the stomach to vent ingested

  17. Cardiovascular coupling analysis with high-resolution joint symbolic dynamics in patients suffering from acute schizophrenia

    International Nuclear Information System (INIS)

    Schulz, Steffen; Tupaika, Nadine; Voss, Andreas; Berger, Sandy; Bär, Karl-Jürgen; Haueisen, Jens

    2013-01-01

    Besides the well-known cardiac risk factors for schizophrenia, increasing concerns have been raised regarding the cardiac side-effects of antipsychotic medications. A bivariate analysis of autonomic regulation, based on cardiovascular coupling, can provide additional information about heart rate (HR) and blood pressure regulatory patterns within the complex interactions of the cardiovascular system. We introduce a new high-resolution coupling analysis method (HRJSD) based on joint symbolic dynamics (JSD), which is characterized by three symbols, a threshold (individual dynamic variability, physiological) for time series transformation and eight coupling pattern families. This is based on a redundancy reduction strategy used to quantify and characterize cardiovascular couplings. In this study, short-term (30 min) HR and systolic blood pressure (SP) time series of 42 unmedicated (UNMED) and 42 medicated patients (MED) suffering from acute schizophrenia were analysed to establish the suitability of the new method for quantifying the effects of antipsychotics on cardiovascular couplings. We were able to demonstrate that HRJSD, applying the threshold based on spontaneous baroreflex sensitivity (BRS) estimation, revealed eight significant pattern families that were able to quantify the anti-cholinergic effects of antipsychotics and the related changes of cardiovascular regulation (coupling) in MED in comparison to UNMED. This was in contrast to the simple JSD, BRS (sequence method) and only partly to standard linear HR variability indices. HRJSD provides strong evidence that autonomic regulation in MED seems to be, to some extent, predominated by invariable HR responses in combination with alternating SP values in contrast to UNMED, indicating an impairment of the baroreflex control feedback loop in MED. Surrogate data analysis was applied to test for the significance and nonlinearity of cardiovascular couplings in the original data due to medical treatment with

  18. The Effects of Moderate- and High-Fidelity Patient Simulator Use on Critical Thinking in Associate Degree Nursing Students

    Science.gov (United States)

    Vieck, Jana

    2013-01-01

    The purpose of this study was to examine the impact of moderate- and high-fidelity patient simulator use on the critical thinking skills of associate degree nursing students. This quantitative study used a quasi-experimental design and the Health Sciences Reasoning Test (HSRT) to evaluate the critical thinking skills of third semester nursing…

  19. Development of High Precision Tsunami Runup Calculation Method Coupled with Structure Analysis

    Science.gov (United States)

    Arikawa, Taro; Seki, Katsumi; Chida, Yu; Takagawa, Tomohiro; Shimosako, Kenichiro

    2017-04-01

    The 2011 Great East Japan Earthquake (GEJE) has shown that tsunami disasters are not limited to inundation damage in a specified region, but may destroy a wide area, causing a major disaster. Evaluating standing land structures and damage to them requires highly precise evaluation of three-dimensional fluid motion - an expensive process. Our research goals were thus to develop a coupling STOC-CADMAS (Arikawa and Tomita, 2016) coupling with the structure analysis (Arikawa et. al., 2009) to efficiently calculate all stages from tsunami source to runup including the deformation of structures and to verify their applicability. We also investigated the stability of breakwaters at Kamaishi Bay. Fig. 1 shows the whole of this calculation system. The STOC-ML simulator approximates pressure by hydrostatic pressure and calculates the wave profiles based on an equation of continuity, thereby lowering calculation cost, primarily calculating from a e epi center to the shallow region. As a simulator, STOC-IC solves pressure based on a Poisson equation to account for a shallower, more complex topography, but reduces computation cost slightly to calculate the area near a port by setting the water surface based on an equation of continuity. CS3D also solves a Navier-Stokes equation and sets the water surface by VOF to deal with the runup area, with its complex surfaces of overflows and bores. STR solves the structure analysis including the geo analysis based on the Biot's formula. By coupling these, it efficiently calculates the tsunami profile from the propagation to the inundation. The numerical results compared with the physical experiments done by Arikawa et. al.,2012. It was good agreement with the experimental ones. Finally, the system applied to the local situation at Kamaishi bay. The almost breakwaters were washed away, whose situation was similar to the damage at Kamaishi bay. REFERENCES T. Arikawa and T. Tomita (2016): "Development of High Precision Tsunami Runup

  20. Fuzzy Control of Cold Storage Refrigeration System with Dynamic Coupling Compensation

    Directory of Open Access Journals (Sweden)

    Xiliang Ma

    2018-01-01

    Full Text Available Cold storage refrigeration systems possess the characteristics of multiple input and output and strong coupling, which brings challenges to the optimize control. To reduce the adverse effects of the coupling and improve the overall control performance of cold storage refrigeration systems, a control strategy with dynamic coupling compensation was studied. First, dynamic model of a cold storage refrigeration system was established based on the requirements of the control system. At the same time, the coupling between the components was studied. Second, to reduce the adverse effects of the coupling, a fuzzy controller with dynamic coupling compensation was designed. As for the fuzzy controller, a self-tuning fuzzy controller was served as the primary controller, and an adaptive neural network was adopted to compensate the dynamic coupling. Finally, the proposed control strategy was employed to the cold storage refrigeration system, and simulations were carried out in the condition of start-up, variable load, and variable degree of superheat, respectively. The simulation results verify the effectiveness of the fuzzy control method with dynamic coupling compensation.

  1. Long Alkyl Chain Organophosphorus Coupling Agents for in Situ Surface Functionalization by Reactive Milling

    Directory of Open Access Journals (Sweden)

    Annika Betke

    2014-08-01

    Full Text Available Innovative synthetic approaches should be simple and environmentally friendly. Here, we present the surface modification of inorganic submicrometer particles with long alkyl chain organophosphorus coupling agents without the need of a solvent, which makes the technique environmentally friendly. In addition, it is of great benefit to realize two goals in one step: size reduction and, simultaneously, surface functionalization. A top-down approach for the synthesis of metal oxide particles with in situ surface functionalization is used to modify titania with long alkyl chain organophosphorus coupling agents. A high energy planetary ball mill was used to perform reactive milling using titania as inorganic pigment and long alkyl chain organophosphorus coupling agents like dodecyl and octadecyl phosphonic acid. The final products were characterized by IR, NMR and X-ray fluorescence spectroscopy, thermal and elemental analysis as well as by X-ray powder diffraction and scanning electron microscopy. The process entailed a tribochemical phase transformation from the starting material anatase to a high-pressure modification of titania and the thermodynamically more stable rutile depending on the process parameters. Furthermore, the particles show sizes between 100 nm and 300 nm and a degree of surface coverage up to 0.8 mmol phosphonate per gram.

  2. Mental Health of Young Couples Referred to Premarriage Consulting Center of Kashan

    Directory of Open Access Journals (Sweden)

    Zahra Sepehrmanesh

    2016-12-01

    Full Text Available Background and Objective: Marriage is base of family creation and human race reproduction. Evaluation mental health of couples; diagnosis and treatment of mental disorder are essential and should be considered before marriage. The aim of this study was to investigate the mental health in young couple referred to consulting center before marriage.Materials and Methods: This cross-sectional study was carried out on 194 young couples. The data collection instruments included the Goldberg's General Health Questionnaire (which has 4 subunits depression, anxiety, somatic symptoms and function and a questionnaire form consist of personal information and factors associated with mental health. Data were analyzed using, Chi-Square or Fisher exact test and t- tests.Results: The mean (SD total GHQ score was 22.3 (8.8 in females and 18.7 (8.5 in men (P=0.004. 29.9 % men and 37% women had mental health problem. The mean (SD total GHQ score was 21.9 (9.1 in the age group 21 to 25 which was higher than the other age groups, and in those with a higher diploma degree was 23.3 (11.7 which was higher than the other educational groups (P= 0.005.Conclusion: Young couples with age 21-25 years old, females and couples with high educational levels had lower mental health than other groups. Therefore, early screening and diagnosis of these problems can prevent impact of these disorders on job performance and social and interpersonal relationship.

  3. Selection of Highly Expressed Gene Variants in Escherichia coli Using Translationally Coupled Antibiotic Selection Markers

    DEFF Research Database (Denmark)

    Rennig, Maja; Daley, Daniel O.; Nørholm, Morten H. H.

    2018-01-01

    Strategies to select highly expressed variants of a protein coding sequence are usually based on trial-and-error approaches, which are time-consuming and expensive. We address this problem using translationally coupled antibiotic resistance markers. The system requires that the target gene can...

  4. Steady-State Anderson Accelerated Coupling of Lattice Boltzmann and Navier–Stokes Solvers

    KAUST Repository

    Atanasov, Atanas

    2016-10-17

    We present an Anderson acceleration-based approach to spatially couple three-dimensional Lattice Boltzmann and Navier–Stokes (LBNS) flow simulations. This allows to locally exploit the computational features of both fluid flow solver approaches to the fullest extent and yields enhanced control to match the LB and NS degrees of freedom within the LBNS overlap layer. Designed for parallel Schwarz coupling, the Anderson acceleration allows for the simultaneous execution of both Lattice Boltzmann and Navier–Stokes solver. We detail our coupling methodology, validate it, and study convergence and accuracy of the Anderson accelerated coupling, considering three steady-state scenarios: plane channel flow, flow around a sphere and channel flow across a porous structure. We find that the Anderson accelerated coupling yields a speed-up (in terms of iteration steps) of up to 40% in the considered scenarios, compared to strictly sequential Schwarz coupling.

  5. A Single-Stage High-Power-Factor Light-Emitting Diode (LED Driver with Coupled Inductors for Streetlight Applications

    Directory of Open Access Journals (Sweden)

    Chun-An Cheng

    2017-02-01

    Full Text Available This paper presents and implements a single-stage high-power-factor light-emitting diode (LED driver with coupled inductors, suitable for streetlight applications. The presented LED driver integrates an interleaved buck-boost power factor correction (PFC converter with coupled inductors and a half-bridge-type series-resonant converter cascaded with a full-bridge rectifier into a single-stage power conversion circuit. Coupled inductors inside the interleaved buck-boost PFC converter sub-circuit are designed to operate in discontinuous conduction mode (DCM for achieving input-current shaping, and the half-bridge-type series resonant converter cascaded with a full-bridge rectifier is designed for obtaining zero-voltage switching (ZVS on two power switches to reduce their switching losses. Analysis of operational modes and design equations for the presented LED driver are described and included. In addition, the presented driver features a high power factor, low total harmonic distortion (THD of input current, and soft switching. Finally, a prototype driver is developed and implemented to supply a 165-W-rated LED streetlight module with utility-line input voltages ranging from 210 to 230 V. Experimental results demonstrate that high power factor (>0.99, low utility-line current THD (<7%, low-output voltage ripples (<1%, low-output current ripples (<10%, and high circuit efficiency (>90% are obtained in the presented single-stage driver for LED streetlight applications.

  6. Single Switch Nonisolated Ultra-Step-Up DC-DC Converter with an Integrated Coupled Inductor for High Boost Applications

    DEFF Research Database (Denmark)

    Siwakoti, Yam P.; Blaabjerg, Frede

    2017-01-01

    This paper introduces a new single-switch nonisolated dc-dc converter with very high voltage gain and reduced semiconductor voltage stress. The converter utilizes an integrated autotransformer and a coupled inductor on the same core in order to achieve a very high voltage gain without using extreme...... duty cycle. Furthermore, a passive lossless clamp circuit recycles the leakage energy of the coupled magnetics and alleviates the voltage spikes across the main switch. This feature along with low stress on the switching device enables the designer to use a low voltage and low RDS-on MOSFET, which...

  7. [Impact of introduction of O2 on the welding arc of gas pool coupled activating TIG].

    Science.gov (United States)

    Huang, Yong; Wang, Yan-Lei; Zhang, Zhi-Guo

    2014-05-01

    In the present paper, Boltzmann plot method was applied to analyze the temperature distributions of the are plasma when the gas pool coupled activating TIG welding was at different coupling degrees with the outer gas being O2. Based on this study of temperature distributions, the changing regularities of are voltage and are appearance were studied. The result shows that compared with traditional TIG welding, the introduction of O2 makes the welding arc constricted slightly, the temperature of the are center build up, and the are voltage increase. When argon being the inner gas, oxygen serving as the outer gas instead of argon makes the are constricted more obviously. When the coupling degree increases from 0 to 2, the temperature of the are center and the are voltage both increase slightly. In the gas pool coupled activating TIG welding the are is constricted not obviously, and the reason why the weld penetration is improved dramatically in the welding of stainless steel is not are constriction.

  8. Examining Electron-Boson Coupling Using Time-Resolved Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sentef, Michael; Kemper, Alexander F.; Moritz, Brian; Freericks, James K.; Shen, Zhi-Xun; Devereaux, Thomas P.

    2013-12-26

    Nonequilibrium pump-probe time-domain spectroscopies can become an important tool to disentangle degrees of freedom whose coupling leads to broad structures in the frequency domain. Here, using the time-resolved solution of a model photoexcited electron-phonon system, we show that the relaxational dynamics are directly governed by the equilibrium self-energy so that the phonon frequency sets a window for “slow” versus “fast” recovery. The overall temporal structure of this relaxation spectroscopy allows for a reliable and quantitative extraction of the electron-phonon coupling strength without requiring an effective temperature model or making strong assumptions about the underlying bare electronic band dispersion.

  9. Evidence of weak pair coupling in the penetration depth of bi-based high-Tc superconductors

    International Nuclear Information System (INIS)

    Thompson, J.R.; Sun, Yang Ren; Ossandon, J.G.; Christen, D.K.; Chakoumakos, B.C.; Sales, B.C.; Kerchner, H.R.; Sonder, E.

    1990-01-01

    The magnetic penetration depth λ(T) has been investigated in Bi(Pb)SrCaCuO high-T c compounds having 2- and 3-layers of copper-oxygen per unit cell. Studies of the magnetization in the vortex state were employed and the results were compared with weak and strong coupling calculations. The temperature dependence of λ is described well by BCS theory in the clean limit, giving evidence for weak pair coupling in this family of materials. For the short component of the λ tensor, we obtain values of 292 and 220 nm (T = 0) for Bi-2212 and (BiPb)-2223, respectively

  10. Electromagnetic Pulse Coupling Analysis of Electronic Equipment

    OpenAIRE

    Hong Lei; Qingying LI

    2017-01-01

    High-intensity nuclear explosion caused by high-altitude nuclear electromagnetic pulse through the antenna, metal cables, holes and other channels, coupled with very high energy into the electronic device, and cause serious threats. In this paper, the mechanism, waveform, coupling path and damage effect of nuclear electromagnetic pulse is analyzed, and the coupling mechanism of nuclear electromagnetic pulse is studied.

  11. Dynamic Coupling Analysis of Urbanization and Water Resource Utilization Systems in China

    Directory of Open Access Journals (Sweden)

    Hailiang Ma

    2016-11-01

    Full Text Available While urbanization brings economic and social benefits, it also causes water pollution and other environmental ecological problems. This paper provides a theoretical framework to quantitatively analyze the dynamic relationship between water resource utilization and the process of urbanization. Using data from Jiangsu province, we first construct indices to evaluate urbanization and water resource utilization. We then adopt an entropy model to examine the correlation between urbanization and water resource utilization. In addition, we introduce a dynamic coupling model to analyze and predict the coupling degree between urbanization and water resource utilization. Our analyses show that pairing with rising urbanization during 2002–2014, the overall index of water resource utilization in Jiangsu province has experienced a “decline -rise-decline” trend. Specifically, after the index of water resource utilization reached its lowest point in 2004, it gradually began to rise. Water resource utilization reached its highest value in 2010. The coupling degree between urbanization and water resource utilization was relatively low in 2002 and 2003 varying between −90° and 0°. It has been rising since then. Out-of-sample forecasts indicate that the coupling degree will reach its highest value of 74.799° in 2016, then will start to gradually decline. Jiangsu province was chosen as our studied area because it is one of the selected pilot provinces for China’s economic reform and social development. The analysis of the relationship between provincial water resource utilization and urbanization is essential to the understanding of the dynamic relationship between these two systems. It also serves as an important input for developing national policies for sustainable urbanization and water resource management.

  12. Plastics pipe couplings

    International Nuclear Information System (INIS)

    Glover, J.B.

    1980-07-01

    A method is described of making a pipe coupling of the type comprising a plastics socket and a resilient annular sealing member secured in the mouth thereof, in which the material of at least one component of the coupling is subjected to irradiation with high energy radiation whereby the material is caused to undergo cross-linking. As examples, the coupling may comprise a polyethylene or plasticised PVC socket the material of which is subjected to irradiation, and the sealing member may be moulded from a thermoplastic elastomer which is subjected to irradiation. (U.K.)

  13. Evaluation and optimization of high-performance liquid chromatography coupled with high-resolution mass spectrometry for phospholipid quantitation.

    Science.gov (United States)

    Fu, Mingkun; Xu, Wei; Lu, Qing; Pan, Guoyu; Varga, Csanad

    2014-04-15

    High-performance liquid chromatography coupled with high-resolution mass spectrometry (HPLC/HRMS) provides an attractive alternative to the traditional triple quadrupole mass spectrometry selected reaction monitoring (SRM) methodology in the field of quantitation. An LTQ Orbitrap Velos mass spectrometer coupled with a Shimadzu UHPLC system was used. A mass extraction window (MEW) was defined to mathematically correlate with mass resolving power (MRP). Five MRP measurement conditions at 7500, 15,000, 30,000, 60,000, and 100,000, and five MEW widths at 10%, 20%, 50%, and 100% of ±1000000/MRP, and were utilized as the experimental conditions. Comparison of profile and centroid algorithms was evaluated as well. Selection of pH 8.5 buffer, C4 column, 20% IPA, and 10 ppm H3 PO4 , minimized hydrophobic and silanol interactions to enhance separation. Narrowing the MEW minimized background noise, while over-narrowing the MEW gave signal loss due to mass accuracy deviation. The mass accuracy deviation was larger for lower MRP measurements especially with centriod data, and hence a profile algorithm was recommended. The post-ionization signal suppression was observed with low MRP and was further confirmed with the analysis of multi-level linearity. It was found that the HPLC/HRMS method with conditions of 20% ±1000000/MRP as MEW, 30,000 or 60,000 MRP, and profile algorithm, provide optimum results for quantitation of seven model phospholipids. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Characteristic of 120 degree C thermoluminescence peak of iceland spar

    International Nuclear Information System (INIS)

    Lu Xinwei; Han Jia

    2006-01-01

    The basic characteristic of 120 degree C thermoluminescence peak of iceland spar was studied. The experimental result indicates the longevity of 120 degree C thermoluminescence peak of iceland spar is about 2 h under 30 degree C. The thermoluminescence peak moves to the high temperature when the heating speed increasing. The intensity of 120 degree C thermoluminescence peak of iceland spar is directly proportional to radiation dose under 15 Gy. (authors)

  15. Modification degrees at specific sites on heparan sulphate: an approach to measure chemical modifications on biological molecules with stable isotope labelling

    Science.gov (United States)

    Wu, Zhengliang L.; Lech, Miroslaw

    2005-01-01

    Chemical modification of biological molecules is a general mechanism for cellular regulation. A quantitative approach has been developed to measure the extent of modification on HS (heparan sulphates). Sulphation on HS by sulphotransferases leads to variable sulphation levels, which allows cells to tune their affinities to various extracellular proteins, including growth factors. With stable isotope labelling and HPLC-coupled MS, modification degrees at various O-sulphation sites could be determined. A bovine kidney HS sample was first saturated in vitro with 34S by an OST (O-sulphotransferase), then digested with nitrous acid and analysed with HPLC-coupled MS. The 34S-labelled oligosaccharides were identified based on their unique isotope clusters. The modification degrees at the sulphotransferase recognition sites were obtained by calculating the intensities of isotopic peaks in the isotope clusters. The modification degrees at 3-OST-1 and 6-OST-1 sites were examined in detail. This approach can also be used to study other types of chemical modifications on biological molecules. PMID:15743272

  16. Coupled heat transfer in high temperature transporting system with semitransparent/opaque material

    International Nuclear Information System (INIS)

    Du Shenghua; Xia Xinjin

    2010-01-01

    The heat transfer model of the aerodynamic heating coupled with radiative cooling was developed. The thermal protect system includes the higher heat flux region with high temperature semitransparent material, the heat transporting channel and the lower heat flux region with metal. The control volume method was combined with the Monte Carlo method to calculate the coupled heat transfer of the transporting system, and the thermal equilibrium equation for the transporting channel was solved simultaneously. The effect of the aeroheating flux radio, the area ratio of radiative surfaces, the convective heat transfer coefficient of the heat transporting channel on the radiative surface temperature and the fluid temperature in the heat transporting channel were analyzed. The effect of radiation and conduction in the semitransparent material was discussed. The result shows that to increase the convective heat transfer coefficient in heat flux channel can enhance the heat transporting ability of the system, but the main parameter to effect on the temperature of the heat transporting system is the area ratio of radiative surfaces. (authors)

  17. Optimization of detection system based on inorganic scintillation crystal coupled with a long lightguide

    CERN Document Server

    Globus, M; Ratner, M

    2002-01-01

    Operation characteristics of a scintillation crystal, linked with the photomultiplier by a long transparent lightguide, are considered (such detection systems are used for monitoring the seawater pollution, scintillation measurements in magnetic field, etc.). This system is optimized with respect to the refractive index of the liquid, coupling the crystal with the lightguide, and the roughness degree of the crystal surface. It is shown that the energy resolution of the system can be significantly improved by using the coupling liquid with a refractive index somewhat less than that of the lightguide (a difference of about 0.2 is optimal). Light output and especially energy resolution becomes better with an increase of the roughness degree of the reflecting surface.

  18. Anticommuting variables, internal degrees of freedom, and the Wilson loop

    International Nuclear Information System (INIS)

    Barducci, A.; Casalbuoni, R.; Lusanna, L.

    1981-01-01

    In this paper we show that is possible to give a real physical meaning to theories in which internal degrees of freedom are described by Grassmann variables. The physical theory is defined by means of an averaging procedure in terms of a distribution function in the Grassmann restricted space satisfying all the physical requirements. If we use this result for a scalar particle with inner degrees of freedom (electric charge, colour, ...) interacting with Yang-Mills gauge fields, it turns out that we can define two different classical theories. Taking the average of the coupled particle-field equations of motion, we recover the usual classical theory. Taking instead the average of the solution of such equations we get a theory which is free from all the classical infinities (and so of the causal defects, like runaway solution or pre-acceleration) but also of all the effects of the same order in the charges (like radiation). The main point is that the processes of averaging and integrating the equations of motion do not commute. Then for the case of colour degrees of freedom we study the quantization of the theory by the path-integral method and we show that the functional integration can be done for an arbitrary gluon field simply by using the classical solution. As a result we obtain an expression for the Wilson loop as a functional integral for the internal fermionic degrees of freedom. (orig.)

  19. Spontaneous decoherence of coupled harmonic oscillators confined in a ring

    Science.gov (United States)

    Gong, ZhiRui; Zhang, ZhenWei; Xu, DaZhi; Zhao, Nan; Sun, ChangPu

    2018-04-01

    We study the spontaneous decoherence of coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry-breaking field or surrounding environment, the quantum superposition state prepared in the relative degrees of freedom gradually loses its quantum coherence spontaneously. This spontaneous decoherence is interpreted by the gauge couplings between the center-of-mass and the relative degrees of freedoms, which actually originate from the symmetries of the ring geometry and the corresponding nontrivial boundary conditions. In particular, such spontaneous decoherence does not occur at all at the thermodynamic limit because the nontrivial boundary conditions become the trivial Born-von Karman boundary conditions when the perimeter of the ring container tends to infinity. Our investigation shows that a thermal macroscopic object with certain symmetries has a chance for its quantum properties to degrade even without applying an external symmetry-breaking field or surrounding environment.

  20. Hydrogen production methods efficiency coupled to an advanced high temperature accelerator driven system

    International Nuclear Information System (INIS)

    Rodríguez, Daniel González; Lira, Carlos Alberto Brayner de Oliveira

    2017-01-01

    The hydrogen economy is one of the most promising concepts for the energy future. In this scenario, oil is replaced by hydrogen as an energy carrier. This hydrogen, rather than oil, must be produced in volumes not provided by the currently employed methods. In this work two high temperature hydrogen production methods coupled to an advanced nuclear system are presented. A new design of a pebbled-bed accelerator nuclear driven system called TADSEA is chosen because of the advantages it has in matters of transmutation and safety. For the conceptual design of the high temperature electrolysis process a detailed computational fluid dynamics model was developed to analyze the solid oxide electrolytic cell that has a huge influence on the process efficiency. A detailed flowsheet of the high temperature electrolysis process coupled to TADSEA through a Brayton gas cycle was developed using chemical process simulation software: Aspen HYSYS®. The model with optimized operating conditions produces 0.1627 kg/s of hydrogen, resulting in an overall process efficiency of 34.51%, a value in the range of results reported by other authors. A conceptual design of the iodine-sulfur thermochemical water splitting cycle was also developed. The overall efficiency of the process was calculated performing an energy balance resulting in 22.56%. The values of efficiency, hydrogen production rate and energy consumption of the proposed models are in the values considered acceptable in the hydrogen economy concept, being also compatible with the TADSEA design parameters. (author)

  1. EUROPAIRS: The European project on coupling of High Temperature Reactors with industrial processes

    International Nuclear Information System (INIS)

    Angulo, C.; Bogusch, E.; Bredimas, A.; Delannay, N.; Viala, C.; Ruer, J.; Muguerra, Ph.; Sibaud, E.; Chauvet, V.; Hittner, D.; Fütterer, M.A.; Groot, S. de; Lensa, W. von; Verfondern, K.; Moron, R.; Baudrand, O.; Griffay, G.; Baaten, A.; Segurado-Gimenez, J.

    2012-01-01

    Developers of High Temperature Reactors (HTR) worldwide acknowledge that the main asset for market breakthrough is its unique ability to address growing needs for industrial cogeneration of heat and power (CHP) owing to its high operating temperature and flexibility, adapted power level, modularity and robust safety features. A strong alliance between nuclear and process heat user industries is a necessity for developing such a nuclear system for the conventional process heat market, just as the electro-nuclear development required a close partnership with utilities. Initiating such an alliance is one of the objectives of the EUROPAIRS project ( (www.europairs.eu)) presently on-going in the frame of the Euratom 7th Framework Programme (FP7). Although small and of short duration (21 months), EUROPAIRS is of strategic importance: it generates the boundary conditions for rapid demonstration of collocating HTR with industrial processes as proposed by the European High Temperature Reactor Technology Network (HTR-TN). This paper presents the main goals, the organization and the working approach of EUROPAIRS. It also presents the status of the viability assessment studies for coupling HTR with industrial end-user systems as one of the main pillars of the project. The main goal of the viability assessment is to identify developments required to remove the last technological and licensing barriers for a viable coupling scheme. The study is expected to result in guidelines for directing the choice of an industrial scale prototype.

  2. Hydrogen production methods efficiency coupled to an advanced high temperature accelerator driven system

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, Daniel González; Lira, Carlos Alberto Brayner de Oliveira [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear; Fernández, Carlos García, E-mail: danielgonro@gmail.com, E-mail: mmhamada@ipen.br [Instituto Superior de Tecnologías y Ciencias aplicadas (InSTEC), La Habana (Cuba)

    2017-07-01

    The hydrogen economy is one of the most promising concepts for the energy future. In this scenario, oil is replaced by hydrogen as an energy carrier. This hydrogen, rather than oil, must be produced in volumes not provided by the currently employed methods. In this work two high temperature hydrogen production methods coupled to an advanced nuclear system are presented. A new design of a pebbled-bed accelerator nuclear driven system called TADSEA is chosen because of the advantages it has in matters of transmutation and safety. For the conceptual design of the high temperature electrolysis process a detailed computational fluid dynamics model was developed to analyze the solid oxide electrolytic cell that has a huge influence on the process efficiency. A detailed flowsheet of the high temperature electrolysis process coupled to TADSEA through a Brayton gas cycle was developed using chemical process simulation software: Aspen HYSYS®. The model with optimized operating conditions produces 0.1627 kg/s of hydrogen, resulting in an overall process efficiency of 34.51%, a value in the range of results reported by other authors. A conceptual design of the iodine-sulfur thermochemical water splitting cycle was also developed. The overall efficiency of the process was calculated performing an energy balance resulting in 22.56%. The values of efficiency, hydrogen production rate and energy consumption of the proposed models are in the values considered acceptable in the hydrogen economy concept, being also compatible with the TADSEA design parameters. (author)

  3. EUROPAIRS: The European project on coupling of High Temperature Reactors with industrial processes

    Energy Technology Data Exchange (ETDEWEB)

    Angulo, C., E-mail: carmen.angulo@gdfsuez.com [Tractebel Engineering S.A. (GDF SUEZ), Avenue Ariane 7, 1200 Brussels (Belgium); Bogusch, E. [AREVA NP GmbH, Paul-Gossen-Strasse 100, 91052 Erlangen (Germany); Bredimas, A. [LGI Consulting, 37 rue de la Grange aux Belles, 75010 Paris (France); Delannay, N. [Tractebel Engineering S.A. (GDF SUEZ), Avenue Ariane 7, 1200 Brussels (Belgium); Viala, C. [AREVA NP SAS, 10 rue Juliette Recamier, 69456 Lyon Cedex 06 (France); Ruer, J.; Muguerra, Ph.; Sibaud, E. [SAIPEM S.A., 1/7 Avenue San Fernando, 78884 Saint Quentin en Yvelines Cedex (France); Chauvet, V. [LGI Consulting, 37 rue de la Grange aux Belles, 75010 Paris (France); Hittner, D. [AREVA NP Inc., 3315 Old Forest Road, Lynchburg, VA 24501 (United States); Fuetterer, M.A. [European Commission, Joint Research Centre, 1755ZG Petten (Netherlands); Groot, S. de [Nuclear Research and Consultancy Group, 1755ZG Petten (Netherlands); Lensa, W. von; Verfondern, K. [Forschungszentrum Juelich GmbH, Leo-Brandt-Strasse,52425 Juelich (Germany); Moron, R. [Solvay SA, rue du Prince Albert 33, 1050 Brussels (Belgium); Baudrand, O. [Institut de Radioprotection et de Surete Nucleaire (IRSN), BP 17, 92262 Fontenay-aux-Roses cedex (France); Griffay, G. [Arcelor Mittal Maizieres Research SA, rue Luigi Cherubini 1A5, 39200 Saint Denis (France); Baaten, A. [USG/Baaten Energy Consulting, Burgermeester-Ceulen-Straat 78, 6212CT Maastricht (Netherlands); Segurado-Gimenez, J. [Tractebel Engineering S.A. (GDF SUEZ), Avenue Ariane 7, 1200 Brussels (Belgium)

    2012-10-15

    Developers of High Temperature Reactors (HTR) worldwide acknowledge that the main asset for market breakthrough is its unique ability to address growing needs for industrial cogeneration of heat and power (CHP) owing to its high operating temperature and flexibility, adapted power level, modularity and robust safety features. A strong alliance between nuclear and process heat user industries is a necessity for developing such a nuclear system for the conventional process heat market, just as the electro-nuclear development required a close partnership with utilities. Initiating such an alliance is one of the objectives of the EUROPAIRS project ( (www.europairs.eu)) presently on-going in the frame of the Euratom 7th Framework Programme (FP7). Although small and of short duration (21 months), EUROPAIRS is of strategic importance: it generates the boundary conditions for rapid demonstration of collocating HTR with industrial processes as proposed by the European High Temperature Reactor Technology Network (HTR-TN). This paper presents the main goals, the organization and the working approach of EUROPAIRS. It also presents the status of the viability assessment studies for coupling HTR with industrial end-user systems as one of the main pillars of the project. The main goal of the viability assessment is to identify developments required to remove the last technological and licensing barriers for a viable coupling scheme. The study is expected to result in guidelines for directing the choice of an industrial scale prototype.

  4. Coupling External Radiation Transport Code Results to the GADRAS Detector Response Function

    International Nuclear Information System (INIS)

    Mitchell, Dean J.; Thoreson, Gregory G.; Horne, Steven M.

    2014-01-01

    Simulating gamma spectra is useful for analyzing special nuclear materials. Gamma spectra are influenced not only by the source and the detector, but also by the external, and potentially complex, scattering environment. The scattering environment can make accurate representations of gamma spectra difficult to obtain. By coupling the Monte Carlo Nuclear Particle (MCNP) code with the Gamma Detector Response and Analysis Software (GADRAS) detector response function, gamma spectrum simulations can be computed with a high degree of fidelity even in the presence of a complex scattering environment. Traditionally, GADRAS represents the external scattering environment with empirically derived scattering parameters. By modeling the external scattering environment in MCNP and using the results as input for the GADRAS detector response function, gamma spectra can be obtained with a high degree of fidelity. This method was verified with experimental data obtained in an environment with a significant amount of scattering material. The experiment used both gamma-emitting sources and moderated and bare neutron-emitting sources. The sources were modeled using GADRAS and MCNP in the presence of the external scattering environment, producing accurate representations of the experimental data.

  5. Broadband EIT borehole measurements with high phase accuracy using numerical corrections of electromagnetic coupling effects

    International Nuclear Information System (INIS)

    Zhao, Y; Zimmermann, E; Wolters, B; Van Waasen, S; Huisman, J A; Treichel, A; Kemna, A

    2013-01-01

    Electrical impedance tomography (EIT) is gaining importance in the field of geophysics and there is increasing interest for accurate borehole EIT measurements in a broad frequency range (mHz to kHz) in order to study subsurface properties. To characterize weakly polarizable soils and sediments with EIT, high phase accuracy is required. Typically, long electrode cables are used for borehole measurements. However, this may lead to undesired electromagnetic coupling effects associated with the inductive coupling between the double wire pairs for current injection and potential measurement and the capacitive coupling between the electrically conductive shield of the cable and the electrically conductive environment surrounding the electrode cables. Depending on the electrical properties of the subsurface and the measured transfer impedances, both coupling effects can cause large phase errors that have typically limited the frequency bandwidth of field EIT measurements to the mHz to Hz range. The aim of this paper is to develop numerical corrections for these phase errors. To this end, the inductive coupling effect was modeled using electronic circuit models, and the capacitive coupling effect was modeled by integrating discrete capacitances in the electrical forward model describing the EIT measurement process. The correction methods were successfully verified with measurements under controlled conditions in a water-filled rain barrel, where a high phase accuracy of 0.8 mrad in the frequency range up to 10 kHz was achieved. The corrections were also applied to field EIT measurements made using a 25 m long EIT borehole chain with eight electrodes and an electrode separation of 1 m. The results of a 1D inversion of these measurements showed that the correction methods increased the measurement accuracy considerably. It was concluded that the proposed correction methods enlarge the bandwidth of the field EIT measurement system, and that accurate EIT measurements can now

  6. Worldline path integrals for fermions with general couplings

    International Nuclear Information System (INIS)

    D'Hoker, E.; Gagne, D.G.

    1996-01-01

    We derive a worldline path integral representation for the effective action of a multiplet of Dirac fermions coupled to the most general set of matrix-valued scalar, pseudoscalar, vector, axial vector and antisymmetric tensor background fields. By representing internal degrees of freedom in terms of worldline fermions as well, we obtain a formulation which manifestly exhibits chiral gauge invariance. (orig.)

  7. A tightly-coupled domain-decomposition approach for highly nonlinear stochastic multiphysics systems

    Energy Technology Data Exchange (ETDEWEB)

    Taverniers, Søren; Tartakovsky, Daniel M., E-mail: dmt@ucsd.edu

    2017-02-01

    Multiphysics simulations often involve nonlinear components that are driven by internally generated or externally imposed random fluctuations. When used with a domain-decomposition (DD) algorithm, such components have to be coupled in a way that both accurately propagates the noise between the subdomains and lends itself to a stable and cost-effective temporal integration. We develop a conservative DD approach in which tight coupling is obtained by using a Jacobian-free Newton–Krylov (JfNK) method with a generalized minimum residual iterative linear solver. This strategy is tested on a coupled nonlinear diffusion system forced by a truncated Gaussian noise at the boundary. Enforcement of path-wise continuity of the state variable and its flux, as opposed to continuity in the mean, at interfaces between subdomains enables the DD algorithm to correctly propagate boundary fluctuations throughout the computational domain. Reliance on a single Newton iteration (explicit coupling), rather than on the fully converged JfNK (implicit) coupling, may increase the solution error by an order of magnitude. Increase in communication frequency between the DD components reduces the explicit coupling's error, but makes it less efficient than the implicit coupling at comparable error levels for all noise strengths considered. Finally, the DD algorithm with the implicit JfNK coupling resolves temporally-correlated fluctuations of the boundary noise when the correlation time of the latter exceeds some multiple of an appropriately defined characteristic diffusion time.

  8. A versatile ultra high vacuum sample stage with six degrees of freedom

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, A. W.; Tromp, R. M. [IBM T.J. Watson Research Center, 1101 Kitchawan Road, P.O. Box 218, Yorktown Heights, New York 10598 (United States)

    2013-07-15

    We describe the design and practical realization of a versatile sample stage with six degrees of freedom. The stage was designed for use in a Low Energy Electron Microscope, but its basic design features will be useful for numerous other applications. The degrees of freedom are X, Y, and Z, two tilts, and azimuth. All motions are actuated in an ultrahigh vacuum base pressure environment by piezoelectric transducers with integrated position sensors. The sample can be load-locked. During observation, the sample is held at a potential of −15 kV, at temperatures between room temperature and 1500 °C, and in background gas pressures up to 1 × 10{sup −4} Torr.

  9. Masseter muscle surface electromyography in college students with a high degree of anxiety and temporomandibular disorder

    Directory of Open Access Journals (Sweden)

    Eduarda de Lima Amarante

    Full Text Available ABSTRACT Objective: to compare the electrical activity of masseter muscles, bilaterally, according to the presence or absence of Temporomandibular Disorder (TMD in college students with a high degree of anxiety. Methods: the study was conducted with a randomized sample of 31 Speech Therapy students aged between 17 and 32 years; 61.3% (n = 19 were females and 38.7% (n = 12 were males. They were divided into two groups, Group 1 (G1, comprising 11 students with TMD, and Group 2 (G2, composed of 20 students without TMD. The college students answered the State-Trait Anxiety Inventory (STAI for anxiety investigation, and were evaluated by the protocol Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD for TMD diagnosis. The evaluation of muscular electrical activity took into account the records in the conditions of rest, Sustained Maximum Voluntary Activity (SMVA and habitual chewing (HC. The data were analyzed using the version 22 IBM Statistical Package for Social Sciences (SPSS software. The statistical analysis was performed using Student t test to compare means between groups, considering < 0,05 as the significant p-value. Results: college students, of both groups, presented high levels of anxiety traits. Significant statistical differences were observed on the percentage of electrical activity of right masseter muscle in chewing function, as well as muscle fibers recruitment during chewing, which were higher on the group without TMD. Conclusion: college students with TMD and a high degree of anxiety presented lower means of masseter muscle electromyografic activity during chewing, in most conditions assessed, as compared to volunteers without TMD, except for the left masseter muscle in rest and chewing.

  10. The Degree Cycle

    DEFF Research Database (Denmark)

    Wood, Johanna

    2016-01-01

    , empirical data relevant to the development of the degree adverb function is presented and possible relevant constructions identified. It is argued that the degree adverb function of that possibly occurs later than the historical dictionaries indicate. The degree adverb function of this is challenging...

  11. Neutron Star Structure in the Presence of Conformally Coupled Scalar Fields

    Science.gov (United States)

    Sultana, Joseph; Bose, Benjamin; Kazanas, Demosthenes

    2014-01-01

    Neutron star models are studied in the context of scalar-tensor theories of gravity in the presence of a conformally coupled scalar field, using two different numerical equations of state (EoS) representing different degrees of stiffness. In both cases we obtain a complete solution by matching the interior numerical solution of the coupled Einstein-scalar field hydrostatic equations, with an exact metric on the surface of the star. These are then used to find the effect of the scalar field and its coupling to geometry, on the neutron star structure, particularly the maximum neutron star mass and radius. We show that in the presence of a conformally coupled scalar field, neutron stars are less dense and have smaller masses and radii than their counterparts in the minimally coupled case, and the effect increases with the magnitude of the scalar field at the center of the star.

  12. 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.

  13. 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.

  14. Accelerated Electron-Beam Formation with a High Capture Coefficient in a Parallel Coupled Accelerating Structure

    Science.gov (United States)

    Chernousov, Yu. D.; Shebolaev, I. V.; Ikryanov, I. M.

    2018-01-01

    An electron beam with a high (close to 100%) coefficient of electron capture into the regime of acceleration has been obtained in a linear electron accelerator based on a parallel coupled slow-wave structure, electron gun with microwave-controlled injection current, and permanent-magnet beam-focusing system. The high capture coefficient was due to the properties of the accelerating structure, beam-focusing system, and electron-injection system. Main characteristics of the proposed systems are presented.

  15. Natural phosphate-supported palladium: A highly efficient and recyclable catalyst for the suzuki-miyaura coupling under microwave irradiation

    KAUST Repository

    Hassine, Ayoub; Bouhrara, Mohamed; Sebti, Said; Solhy, Abderrahim; Mahfouz, Remi; Luart, Denis; Lene, Christophe; Fihri, Aziz

    2015-01-01

    This report explores Suzuki-Miyaura coupling under microwave irradiation, using a new generation of catalyst that is based on natural phosphate (NP) impregnated by palladium. This catalyst was prepared by the treatment of natural phosphate with bis(benzonitrile)palladium(II) chloride in acetone at room temperature. The catalyst displayed high catalytic activity for the Suzuki-Miyaura coupling of aryl bromides and chlorides with aryl boronic acids in pure water and with the use of microwave irradiation. The low-cost and availability of the solid support, mild reaction conditions, high yields of desired products, recyclability of the catalyst and short reaction times are the notable features of these methods.

  16. Natural phosphate-supported palladium: A highly efficient and recyclable catalyst for the suzuki-miyaura coupling under microwave irradiation

    KAUST Repository

    Hassine, Ayoub

    2015-01-19

    This report explores Suzuki-Miyaura coupling under microwave irradiation, using a new generation of catalyst that is based on natural phosphate (NP) impregnated by palladium. This catalyst was prepared by the treatment of natural phosphate with bis(benzonitrile)palladium(II) chloride in acetone at room temperature. The catalyst displayed high catalytic activity for the Suzuki-Miyaura coupling of aryl bromides and chlorides with aryl boronic acids in pure water and with the use of microwave irradiation. The low-cost and availability of the solid support, mild reaction conditions, high yields of desired products, recyclability of the catalyst and short reaction times are the notable features of these methods.

  17. Conduction-coupled Tesla transformer.

    Science.gov (United States)

    Reed, J L

    2015-03-01

    A proof-of-principle Tesla transformer circuit is introduced. The new transformer exhibits the high voltage-high power output signal of shock-excited transformers. The circuit, with specification of proper circuit element values, is capable of obtaining extreme oscillatory voltages. The primary and secondary portions of the circuit communicate solely by conduction. The destructive arcing between the primary and secondary inductors in electromagnetically coupled transformers is ubiquitous. Flashover is eliminated in the new transformer as the high-voltage inductors do not interpenetrate and so do not possess an annular volume of electric field. The inductors are remote from one another. The high voltage secondary inductor is isolated in space, except for a base feed conductor, and obtains earth by its self-capacitance to the surroundings. Governing equations, for the ideal case of no damping, are developed from first principles. Experimental, theoretical, and circuit simulator data are presented for the new transformer. Commercial high-temperature superconductors are discussed as a means to eliminate the counter-intuitive damping due to small primary inductances in both the electromagnetic-coupled and new conduction-coupled transformers.

  18. Pre-marital genetic counselling to consanguineous couples: attitudes, beliefs and decisions among counselled, noncounselled and unrelated couples in Israel.

    Science.gov (United States)

    Shiloh, S; Reznik, H; Bat-Miriam-Katznelson, M; Goldman, B

    1995-11-01

    Semi-structured interviews were conducted with 65 Israeli subjects who received genetic counselling while considering marriage to a close relative, 40 subjects married to a close relative who did not receive pre-marital genetic counselling, and 125 controls married to a nonrelative and never having considered marrying a relative. It was found that 72% of the consanguineous couples who received pre-marital genetic counselling proceeded with their plans and married their relative; 86% of them reported that the counselling influenced their final decision to some degree. Counsellees' appraisals of genetic counselling revealed unfulfilled expectations to obtain more definitive answers, and mixed reactions to the nondirective approach applied by the counsellors. Comparisons between consanguineous and control couples revealed different views about consanguinity in general, and genetic risks in particular. Consanguineous couples, unlike controls, perceived consanguinity as an ordinary form of marriage, and had more favorable attitudes towards it. Compared to the noncounselled consanguineous group, consanguineous couples who received pre-marital genetic counselling had fewer children, estimated their genetic risk as lower but its subjective significance as higher, and perceived genetic disorders as more severe. The implications of these results are discussed from both theoretical and practical standpoints.

  19. Refractive surgery: Is the new small-incision lenticule extraction (SMILE) technique equal to or better than the standard flap-and-ablation (FS-LASIK) technique for treating high-degree myopia?

    DEFF Research Database (Denmark)

    Hansen, Rasmus Søgaard; Lyhne, Niels; Grauslund, Jakob

    Field: Ophthalmology Introduction: Corneal laser surgery for myopia (nearsightedness) is one of the most performed surgical procedures today. FS-LASIK has been the dominating surgical technique for almost two decades, but a shift to the new less invasive SMILE technique might be underway. However...... the literature on SMILE is sparse, especially for high-degree myopia (six or more dioptres (D)). We hypothesize that the accuracy, efficacy, stability and safety after SMILE is equal to or better than FS-LASIK up to three months post-operatively for high-degree myopia. Methods: Retrospective study of 1214 eyes...... treated with SMILE or FS-LASIK for high-degree myopia from 2011-2013 at the Department of Ophthalmology, Odense University Hospital, Denmark. Inclusion criteria: Best spectacle-corrected visual acuity (BSCVA) of 20/25 or better on Snellen chart, and no other ocular condition than high-degree myopia...

  20. Starch degradability of dry and ensiled high-moisture grains of corn hybrids with different textures at different grinding degrees

    OpenAIRE

    Wagner dos Reis; Ciniro Costa; Paulo Roberto de Lima Meirelles; Marina Gabriela Berchiol da Silva; Marco Aurélio Factori; Cristiano Magalhães Pariz; Simony Alves Mendonça; Erikelly Aline Ribeiro de Santana

    2011-01-01

    This research evaluated corn grains with flint and dent texture (ensiled high-moisture or dried), submitted to grinding degrees, using the in situ ruminal degradation technique. Three rumen canulated adult sheeps were used in a complete randomized design, using a factorial outline 2 x 2 x 3, with two corn hybrids (flint and dent texture), two conservation methods (ensiled high-moisture and dry) and three grinding degress (whole, coarsely and finely ground, corresponding to the sieve of 12; 10...

  1. Evidence for trapping and collectivization of resonances at strong coupling

    International Nuclear Information System (INIS)

    Herzberg, R.D.; Brentano, P. von; Rotter, I.

    1993-01-01

    The behavior of 22 neutron resonances in 53 Cr is investigated as a function of the coupling-strength parameter μ and of the degree of overlapping. Starting from a doorway picture at small μ, the widths of 21 resonances increase with increasing μ at the cost of the width of the original 'single-particle doorway resonance'. At μ≅1, the widths of most states decrease again. At μ→10 the widths of these 'trapped' states vanish while 'collective' states are formed which gather the widths. Thus we again observe a doorway picture at strong coupling. At μ=1, the energies and widths of the resonances are fitted to the experimental data. At this coupling strength, most resonances investigated resemble trapped modes. (orig.)

  2. Survey of Foreign Language Entrance and Degree Requirements for the Bachelor of Arts Degree in United States Institutions of High Education, Fall 1974. Final Report.

    Science.gov (United States)

    Brod, Richard I.

    This report presents the results of the ninth survey of foreign language entrance and degree requirements in United States colleges and universities that grant a bachelor of arts degree. The survey was conducted in 1974 by the Modern Language Association, and was directed at foreign language department chairmen. Responses were received from 98.8…

  3. Electrocatalytic properties of carbon-supported Pt-Ru catalysts with the high alloying degree for formic acid electrooxidation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu.; Zhou, Yiming; Tang, Yawen; Lu, Tianhong [College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097 (China)

    2010-07-01

    A series of carbon-supported bimetallic Pt-Ru catalysts with high alloying degree and different Pt/Ru atomic ratio have been prepared by a chemical reduction method in the H{sub 2}O/ethanol/tetrahydrofuran (THF) mixture solvent. The structural and electronic properties of catalysts are characterized using X-ray reflection (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM). The electrooxidation of formic acid on these Pt-Ru nanoparticles are investigated by using cyclic voltammetry, chronoamperometry and CO-stripping measurements. The results of electrochemical measurements illustrate that the alloying degree and Pt/Ru atomic ratio of Pt-Ru catalyst play an important role in the electrocatalytic activity of the Pt-Ru/C catalyst for formic acid electrooxidation due to the bifunctional mechanism and the electronic effect. Since formic acid is an intermediate in the methanol electrooxidation on Pt electrode in acidic electrolyte, the observation provides an additional fundamental understanding of the structure-activity relationship of Pt-Ru catalyst for methanol electrooxidation. (author)

  4. Application of the Arbitrarily High Order Method to Coupled Electron Photon Transport

    International Nuclear Information System (INIS)

    Duo, Jose Ignacio

    2004-01-01

    This work is about the application of the Arbitrary High Order Nodal Method to coupled electron photon transport.A Discrete Ordinates code was enhanced and validated which permited to evaluate the advantages of using variable spatial development order per particle.The results obtained using variable spatial development and adaptive mesh refinement following an a posteriori error estimator are encouraging.Photon spectra for clinical accelerator target and, dose and charge depositio profiles are simulated in one-dimensional problems using cross section generated with CEPXS code.Our results are in good agreement with ONELD and MCNP codes

  5. Local control on precipitation in a fully coupled climate-hydrology model.

    Science.gov (United States)

    Larsen, Morten A D; Christensen, Jens H; Drews, Martin; Butts, Michael B; Refsgaard, Jens C

    2016-03-10

    The ability to simulate regional precipitation realistically by climate models is essential to understand and adapt to climate change. Due to the complexity of associated processes, particularly at unresolved temporal and spatial scales this continues to be a major challenge. As a result, climate simulations of precipitation often exhibit substantial biases that affect the reliability of future projections. Here we demonstrate how a regional climate model (RCM) coupled to a distributed hydrological catchment model that fully integrates water and energy fluxes between the subsurface, land surface, plant cover and the atmosphere, enables a realistic representation of local precipitation. Substantial improvements in simulated precipitation dynamics on seasonal and longer time scales is seen for a simulation period of six years and can be attributed to a more complete treatment of hydrological sub-surface processes including groundwater and moisture feedback. A high degree of local influence on the atmosphere suggests that coupled climate-hydrology models have a potential for improving climate projections and the results further indicate a diminished need for bias correction in climate-hydrology impact studies.

  6. Numerical simulation of aerodynamic performance of a couple multiple units high-speed train

    Science.gov (United States)

    Niu, Ji-qiang; Zhou, Dan; Liu, Tang-hong; Liang, Xi-feng

    2017-05-01

    In order to determine the effect of the coupling region on train aerodynamic performance, and how the coupling region affects aerodynamic performance of the couple multiple units trains when they both run and pass each other in open air, the entrance of two such trains into a tunnel and their passing each other in the tunnel was simulated in Fluent 14.0. The numerical algorithm employed in this study was verified by the data of scaled and full-scale train tests, and the difference lies within an acceptable range. The results demonstrate that the distribution of aerodynamic forces on the train cars is altered by the coupling region; however, the coupling region has marginal effect on the drag and lateral force on the whole train under crosswind, and the lateral force on the train cars is more sensitive to couple multiple units compared to the other two force coefficients. It is also determined that the component of the coupling region increases the fluctuation of aerodynamic coefficients for each train car under crosswind. Affected by the coupling region, a positive pressure pulse was introduced in the alternating pressure produced by trains passing by each other in the open air, and the amplitude of the alternating pressure was decreased by the coupling region. The amplitude of the alternating pressure on the train or on the tunnel was significantly decreased by the coupling region of the train. This phenomenon did not alter the distribution law of pressure on the train and tunnel; moreover, the effect of the coupling region on trains passing by each other in the tunnel is stronger than that on a single train passing through the tunnel.

  7. Capillary electrophoresis - inductively coupled plasma mass spectrometry (CE-ICPMS) coupling to assess pentavalent actinides thermodynamic constants

    International Nuclear Information System (INIS)

    Topin, S.; Baglan, N.; Aupiais, J.

    2009-01-01

    Full text: Aiming to investigate plutonium speciation at trace levels, we coupled capillary electrophoresis, a high resolution separation technique with inductively coupled plasma mass spectrometry, a detector with high sensitivity for plutonium. The research work performed to optimize the coupling is discussed based on the following criteria: the migration time, the resolution and the detection limit. The capabilities of the analytical tool are demonstrated by determining thermodynamic constants for pentavalent plutonium, and neptunium as a reference, in the presence of inorganic ligands. (author)

  8. Survival in vivo of platelets stored for 48 hours in the buffycoat at 4 degrees C compared to platelet rich plasma stored at 22 degrees C

    NARCIS (Netherlands)

    Pietersz, R. N.; Loos, J. A.; Reesink, H. W.

    1987-01-01

    High speed centrifugation allows separation of whole blood into cell free plasma, a buffy coat and leukocyte poor red cells. The buffy coat can be used for the preparation of platelet concentrates. High lactate production at 22 degrees C requires storage of the buffy coat at 4 degrees C. Survival in

  9. Quantum-coherent coupling of a mechanical oscillator to an optical cavity mode.

    Science.gov (United States)

    Verhagen, E; Deléglise, S; Weis, S; Schliesser, A; Kippenberg, T J

    2012-02-01

    Optical laser fields have been widely used to achieve quantum control over the motional and internal degrees of freedom of atoms and ions, molecules and atomic gases. A route to controlling the quantum states of macroscopic mechanical oscillators in a similar fashion is to exploit the parametric coupling between optical and mechanical degrees of freedom through radiation pressure in suitably engineered optical cavities. If the optomechanical coupling is 'quantum coherent'--that is, if the coherent coupling rate exceeds both the optical and the mechanical decoherence rate--quantum states are transferred from the optical field to the mechanical oscillator and vice versa. This transfer allows control of the mechanical oscillator state using the wide range of available quantum optical techniques. So far, however, quantum-coherent coupling of micromechanical oscillators has only been achieved using microwave fields at millikelvin temperatures. Optical experiments have not attained this regime owing to the large mechanical decoherence rates and the difficulty of overcoming optical dissipation. Here we achieve quantum-coherent coupling between optical photons and a micromechanical oscillator. Simultaneously, coupling to the cold photon bath cools the mechanical oscillator to an average occupancy of 1.7 ± 0.1 motional quanta. Excitation with weak classical light pulses reveals the exchange of energy between the optical light field and the micromechanical oscillator in the time domain at the level of less than one quantum on average. This optomechanical system establishes an efficient quantum interface between mechanical oscillators and optical photons, which can provide decoherence-free transport of quantum states through optical fibres. Our results offer a route towards the use of mechanical oscillators as quantum transducers or in microwave-to-optical quantum links.

  10. Computational model for a high temperature electrolyzer coupled to a HTTR for efficient nuclear hydrogen production

    International Nuclear Information System (INIS)

    Gonzalez, Daniel; Rojas, Leorlen; Rosales, Jesus; Castro, Landy; Gamez, Abel; Brayner, Carlos; Garcia, Lazaro; Garcia, Carlos; Torre, Raciel de la; Sanchez, Danny

    2015-01-01

    High temperature electrolysis process coupled to a very high temperature reactor (VHTR) is one of the most promising methods for hydrogen production using a nuclear reactor as the primary heat source. However there are not references in the scientific publications of a test facility that allow to evaluate the efficiency of the process and other physical parameters that has to be taken into consideration for its accurate application in the hydrogen economy as a massive production method. For this lack of experimental facilities, mathematical models are one of the most used tools to study this process and theirs flowsheets, in which the electrolyzer is the most important component because of its complexity and importance in the process. A computational fluid dynamic (CFD) model for the evaluation and optimization of the electrolyzer of a high temperature electrolysis hydrogen production process flowsheet was developed using ANSYS FLUENT®. Electrolyzer's operational and design parameters will be optimized in order to obtain the maximum hydrogen production and the higher efficiency in the module. This optimized model of the electrolyzer will be incorporated to a chemical process simulation (CPS) code to study the overall high temperature flowsheet coupled to a high temperature accelerator driven system (ADS) that offers advantages in the transmutation of the spent fuel. (author)

  11. Computational model for a high temperature electrolyzer coupled to a HTTR for efficient nuclear hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Daniel; Rojas, Leorlen; Rosales, Jesus; Castro, Landy; Gamez, Abel; Brayner, Carlos, E-mail: danielgonro@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Garcia, Lazaro; Garcia, Carlos; Torre, Raciel de la, E-mail: lgarcia@instec.cu [Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba); Sanchez, Danny [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil)

    2015-07-01

    High temperature electrolysis process coupled to a very high temperature reactor (VHTR) is one of the most promising methods for hydrogen production using a nuclear reactor as the primary heat source. However there are not references in the scientific publications of a test facility that allow to evaluate the efficiency of the process and other physical parameters that has to be taken into consideration for its accurate application in the hydrogen economy as a massive production method. For this lack of experimental facilities, mathematical models are one of the most used tools to study this process and theirs flowsheets, in which the electrolyzer is the most important component because of its complexity and importance in the process. A computational fluid dynamic (CFD) model for the evaluation and optimization of the electrolyzer of a high temperature electrolysis hydrogen production process flowsheet was developed using ANSYS FLUENT®. Electrolyzer's operational and design parameters will be optimized in order to obtain the maximum hydrogen production and the higher efficiency in the module. This optimized model of the electrolyzer will be incorporated to a chemical process simulation (CPS) code to study the overall high temperature flowsheet coupled to a high temperature accelerator driven system (ADS) that offers advantages in the transmutation of the spent fuel. (author)

  12. Features of cerebral vascular reactivity in patients with different clinical course of a high degree of myopia

    Directory of Open Access Journals (Sweden)

    G. V. Shkrebets

    2014-07-01

    Full Text Available Purpose: to examine the state rate parameters of cerebral and ocular vessels in patients with glaucoma combined with myopia of high degree.Methods: the study involved 3 groups of patients aged 16-32 years: 1st — 30 patients (60 eyes — with a stationary myopia of 6.5 to 9.0 D and normal intraocular pressure (IOP; 2nd — 23 patients (46 eyes — with a high degree of progressive myopia and glaucoma with normalized intraocular pressure during instillation Azopt included 2 subgroups: subgroup A — 14 patients (28 eyes — with ischemic variant of glaucoma; subgroup B — 9 patients (18 eyes — with dyscirculatory variant of glaucoma; 3rd group (control — 10 somatically healthy individuals of similar age. Following a standard ophthalmic examination techniques, as well as color Doppler mapping of the main arteries of the brain and the eyeball on the unit Acuson 128 HR/10 (USA and hypocapnic (with O2 and hypercapnic (CO2 probe.Results: In subgroup 2A patients showed significant (p <0.05 decrease in Vs in the central retinal artery and short posterior cili- ary arteries respectively 38.0% and 32.8% and increase the resistance index (RI of vessels in 21.8% and 22.6%, increase Vs in the middle cerebral artery (MCA at 11.5% and RI by 11.8% compared to the patients the third and first groups, with а hypocapnic test Vs in the MCA decreased by 35.4%, and increased with hypercapnic test for 23.0%; of the subgroup B in central retinal vein to 33.9% and 19.6%, lower Vs and RI in the vertebral artery (VA by 20,0% and 9,1% respectively, with a hypercapnic test Vs in the MCA increased by 32.2%, and decreased during hypocapnic sample at 26.0%.Conclusion: the predominance of the ability of MCA to vasoconstriction combined with reduced blood flow in central retinal artery and short posterior ciliary arteries and cause ischemica variant of glaucoma, slowing blood flow in the vertebrobasilar basin combined with a reduction of venous outflow of the of the

  13. Ion energy and angular distributions in inductively coupled Argon RF discharges

    International Nuclear Information System (INIS)

    Woodworth, J.R.; Riley, M.E.; Meister, D.C.

    1996-03-01

    We report measurements of the energies and angular distributions of positive ions in an inductively coupled argon plasma in a GEC reference cell. Use of two separate ion detectors allowed measurement of ion energies and fluxes as a function of position as well as ion angular distributions on the discharge centerline. The inductive drive on our system produced high plasma densities (up to 10 12 /cm 3 electron densities) and relatively stable plasma potentials. As a result, ion energy distributions typically consisted of a single feature well separated from zero energy. Mean ion energy was independent of rf power and varied inversely with pressure, decreasing from 29 eV to 12 eV as pressure increased form 2.4 m Torr to 50 mTorr. Half-widths of the ion angular distributions in these experiments varied from 5 degrees to 12.5 degrees, or equivalently, transverse temperatures varied form 0.2 to 0.5 eV with the distributions broadening as either pressure or RF power were increased

  14. Electronic couplings for molecular charge transfer: Benchmarking CDFT, FODFT, and FODFTB against high-level ab initio calculations

    Energy Technology Data Exchange (ETDEWEB)

    Kubas, Adam; Blumberger, Jochen, E-mail: j.blumberger@ucl.ac.uk [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Hoffmann, Felix [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, Universitätsstr. 150, 44801 Bochum (Germany); Heck, Alexander; Elstner, Marcus [Institute of Physical Chemistry, Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, 76131 Karlsruhe (Germany); Oberhofer, Harald [Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747 Garching (Germany)

    2014-03-14

    We introduce a database (HAB11) of electronic coupling matrix elements (H{sub ab}) for electron transfer in 11 π-conjugated organic homo-dimer cations. High-level ab inito calculations at the multireference configuration interaction MRCI+Q level of theory, n-electron valence state perturbation theory NEVPT2, and (spin-component scaled) approximate coupled cluster model (SCS)-CC2 are reported for this database to assess the performance of three DFT methods of decreasing computational cost, including constrained density functional theory (CDFT), fragment-orbital DFT (FODFT), and self-consistent charge density functional tight-binding (FODFTB). We find that the CDFT approach in combination with a modified PBE functional containing 50% Hartree-Fock exchange gives best results for absolute H{sub ab} values (mean relative unsigned error = 5.3%) and exponential distance decay constants β (4.3%). CDFT in combination with pure PBE overestimates couplings by 38.7% due to a too diffuse excess charge distribution, whereas the economic FODFT and highly cost-effective FODFTB methods underestimate couplings by 37.6% and 42.4%, respectively, due to neglect of interaction between donor and acceptor. The errors are systematic, however, and can be significantly reduced by applying a uniform scaling factor for each method. Applications to dimers outside the database, specifically rotated thiophene dimers and larger acenes up to pentacene, suggests that the same scaling procedure significantly improves the FODFT and FODFTB results for larger π-conjugated systems relevant to organic semiconductors and DNA.

  15. High-energy scattering in strongly coupled N=4 super Yang-Mills theory

    International Nuclear Information System (INIS)

    Sprenger, Martin

    2014-11-01

    This thesis concerns itself with the analytic structure of scattering amplitudes in strongly coupled N=4 super Yang-Mills theory (abbreviated N = 4 SYM) in the multi-Regge limit. Through the AdS/CFT-correspondence observables in strongly coupled N = 4 SYM are accessible via dual calculations in a weakly coupled string theory on an AdS 5 x S 5 -geometry, in which observables can be calculated using standard perturbation theory. In particular, the calculation of the leading order of the n-gluon amplitude in N = 4 SYM at strong coupling corresponds to the calculation of a minimal surface embedded into AdS 5 . This surface ends on the concatenation of the gluon momenta, which is a light-like curve. The calculation of the minimal surface area can be reduced to finding the solution of a set of non-linear, coupled integral equations, which have no analytic solution in arbitrary kinematics. In this thesis, we therefore specialise to the multi-Regge limit, the n-particle generalisation of the Regge limit. This limit is especially interesting as even in the description of scattering amplitudes in weakly coupled N = 4 SYM in this limit a certain set of Feynman diagrams has to be resummed. This description organises itself into orders of logarithms of the energy involved in the scattering process. In this expansion each order in logarithms includes terms from every order in the coupling constant and therefore contains information about the strong coupling sector of the theory, albeit in a very specific way. This raises the central question of this thesis, which is how much of the analytic structure of the scattering amplitudes in the multi-Regge limit is preserved as we go to the strong coupling regime. We show that the equations governing the area of the minimal surface simplify drastically in the multi-Regge limit, which allows us to obtain analytic results for the scattering amplitudes. We develop an algorithm for the calculation of scattering amplitudes in the multi

  16. A field survey of metal binding to metallothionein and other cytosolic ligands in liver of eels using an on-line isotope dilution method in combination with size exclusion (SE) high pressure liquid chromatography (HPLC) coupled to Inductively Coupled Plasma time-of-flight Mass Spectrometry (ICP-TOFMS).

    Science.gov (United States)

    Van Campenhout, Karen; Goenaga Infante, Heidi; Goemans, Geert; Belpaire, Claude; Adams, Freddy; Blust, Ronny; Bervoets, Lieven

    2008-05-15

    The effect of metal exposure on the accumulation and cytosolic speciation of metals in livers of wild populations of European eel with special emphasis on metallothioneins (MT) was studied. Four sampling sites in Flanders showing different degrees of heavy metal contamination were selected for this purpose. An on-line isotope dilution method in combination with size exclusion (SE) high pressure liquid chromatography (HPLC) coupled to Inductively Coupled Plasma time-of-flight Mass Spectrometry (ICP-TOFMS) was used to study the cytosolic speciation of the metals. The distribution of the metals Cd, Cu, Ni, Pb and Zn among cytosolic fractions displayed strong differences. The cytosolic concentration of Cd, Ni and Pb increased proportionally with the total liver levels. However, the cytosolic concentrations of Cu and Zn only increased above a certain liver tissue threshold level. Cd, Cu and Zn, but not Pb and Ni, were largely associated with the MT pool in correspondence with the environmental exposure and liver tissue concentrations. Most of the Pb and Ni and a considerable fraction of Cu and Zn, but not Cd, were associated to High Molecular Weight (HMW) fractions. The relative importance of the Cu and Zn in the HMW fraction decreased with increasing contamination levels while the MT pool became progressively more important. The close relationship between the cytosolic metal load and the total MT levels or the metals bound on the MT pool indicates that the metals, rather than other stress factors, are the major factor determining MT induction.

  17. Measuring the internal temperature of a levitated nanoparticle in high vacuum

    Science.gov (United States)

    Hebestreit, Erik; Reimann, René; Frimmer, Martin; Novotny, Lukas

    2018-04-01

    The interaction of an object with its surrounding bath can lead to a coupling between the object's internal degrees of freedom and its center-of-mass motion. This coupling is especially important for nanomechanical oscillators, which are among the most promising systems for preparing macroscopic objects in quantum mechanical states. Here we exploit this coupling to derive the internal temperature of a levitated nanoparticle from measurements of its center-of-mass dynamics. For a laser-trapped silica particle in high vacuum, we find an internal temperature of 1000 (60 )K . The measurement and control of the internal temperature of nanomechanical oscillators is of fundamental importance because black-body emission sets limits to the coherence of macroscopic quantum states.

  18. Vibronic coupling density and related concepts

    International Nuclear Information System (INIS)

    Sato, Tohru; Uejima, Motoyuki; Iwahara, Naoya; Haruta, Naoki; Shizu, Katsuyuki; Tanaka, Kazuyoshi

    2013-01-01

    Vibronic coupling density is derived from a general point of view as a one-electron property density. Related concepts as well as their applications are presented. Linear and nonlinear vibronic coupling density and related concepts, orbital vibronic coupling density, reduced vibronic coupling density, atomic vibronic coupling constant, and effective vibronic coupling density, illustrate the origin of vibronic couplings and enable us to design novel functional molecules or to elucidate chemical reactions. Transition dipole moment density is defined as an example of the one-electron property density. Vibronic coupling density and transition dipole moment density open a way to design light-emitting molecules with high efficiency.

  19. Highly sensitive digital optical sensor with large measurement range based on the dual-microring resonator with waveguide-coupled feedback

    International Nuclear Information System (INIS)

    Xiang Xing-Ye; Wang Kui-Ru; Yuan Jin-Hui; Jin Bo-Yuan; Sang Xin-Zhu; Yu Chong-Xiu

    2014-01-01

    We propose a novel high-performance digital optical sensor based on the Mach—Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the sensitivity of the sensor can be orders of magnitude higher than that of a conventional sensor, and high quality factor is not critical in it. Moreover, by optimizing the length of the feedback waveguide to be equal to the perimeter of the ring, the measurement range of the proposed sensor is twice as much as that of the conventional sensor in the weak coupling case

  20. Modelling suction instabilities in soils at varying degrees of saturation

    Directory of Open Access Journals (Sweden)

    Buscarnera Giuseppe

    2016-01-01

    Full Text Available Wetting paths imparted by the natural environment and/or human activities affect the state of soils in the near-surface, promoting transitions across different regimes of saturation. This paper discusses a set of techniques aimed at quantifying the role of hydrologic processes on the hydro-mechanical stability of soil specimens subjected to saturation events. Emphasis is given to the mechanical conditions leading to coupled flow/deformation instabilities. For this purpose, energy balance arguments for three-phase systems are used to derive second-order work expressions applicable to various regimes of saturation. Controllability analyses are then performed to relate such work input with constitutive singularities that reflect the loss of strength under coupled and/or uncoupled hydro-mechanical forcing. A suction-dependent plastic model is finally used to track the evolution of stability conditions in samples subjected to wetting, thus quantifying the growth of the potential for coupled failure modes upon increasing degree of saturation. These findings are eventually linked with the properties of the field equations that govern pore pressure transients, thus disclosing a conceptual link between the onset of coupled hydro-mechanical failures and the evolution of suction with time. Such results point out that mathematical instabilities caused by a non-linear suction dependent behaviour play an important role in the advanced constitutive and/or numerical tools that are commonly used for the analysis of geomechanical problems in the unsaturated zone, and further stress that the relation between suction transients and soil deformations is a key factor for the interpretation of runaway failures caused by intense saturation events.

  1. Global weak solutions for coupled transport processes in concrete walls at high temperatures

    OpenAIRE

    Beneš, Michal; Štefan, Radek

    2012-01-01

    We consider an initial-boundary value problem for a fully nonlinear coupled parabolic system with nonlinear boundary conditions modelling hygro-thermal behavior of concrete at high temperatures. We prove a global existence of a weak solution to this system on an arbitrary time interval. The main result is proved by an approximation procedure. This consists in proving the existence of solutions to mollified problems using the Leray-Schauder theorem, for which a priori estimates are obtained. T...

  2. A discussion of coupling and resonance effects for integrated systems consisting of subsystems

    International Nuclear Information System (INIS)

    Lin, C.W.; Liu, T.H.

    1975-01-01

    Three representative cases are studied to evaluate the interaction effect and to establish the need to include both stiffness and mass of the interacting systems in the system model. The first case is a supported system supported by a two-degrees-of-freedom supporting system. The second case represents two single degree of freedom systems, each supported by itself, but interconnected by a spring. The third case is a single degree of freedom system supported by another single degree of freedom supporting system. In each of the three case studied, the interaction effect is first measured by the difference in their natural frequencies for both the coupled system and the uncoupled systems. Although natural frequencies are important to the dynamic analysis of a system, the ultimate decision of whether the mathematical model is realistic depends on the result of the system response it predicts. With this in mind, case three is then studied with a white noise input. It is found that the root mean square response of both the supporting systems are substantially lower when coupled than when the systems are analyzed separately. Based on the results of this study, guidelines are provided for the subdivision into subsystems. (orig./HP) [de

  3. High modulation bandwidth of a light-emitting diode with surface plasmon coupling (Conference Presentation)

    Science.gov (United States)

    Lin, Chun-Han; Tu, Charng-Gan; Yao, Yu-Feng; Chen, Sheng-Hung; Su, Chia-Ying; Chen, Hao-Tsung; Kiang, Yean-Woei; Yang, Chih-Chung

    2017-02-01

    Besides lighting, LEDs can be used for indoor data transmission. Therefore, a large modulation bandwidth becomes an important target in the development of visible LED. In this regard, enhancing the radiative recombination rate of carriers in the quantum wells of an LED is a useful method since the modulation bandwidth of an LED is related to the carrier decay rate besides the device RC time constant To increase the carrier decay rate in an LED without sacrificing its output power, the technique of surface plasmon (SP) coupling in an LED is useful. In this paper, the increases of modulation bandwidth by reducing mesa size, decreasing active layer thickness, and inducing SP coupling in blue- and green-emitting LEDs are illustrated. The results are demonstrated by comparing three different LED surface structures, including bare p-type surface, GaZnO current spreading layer, and Ag nanoparticles (NPs) for inducing SP coupling. In a single-quantum-well, blue-emitting LED with a circular mesa of 10 microns in radius, SP coupling results in a modulation bandwidth of 528.8 MHz, which is believed to be the record-high level. A smaller RC time constant can lead to a higher modulation bandwidth. However, when the RC time constant is smaller than 0.2 ns, its effect on modulation bandwidth saturates. The dependencies of modulation bandwidth on injected current density and carrier decay time confirm that the modulation bandwidth is essentially inversely proportional to a time constant, which is inversely proportional to the square-root of carrier decay rate and injected current density.

  4. Probing WWγ and WWγγ couplings with high energy photon beams

    International Nuclear Information System (INIS)

    Choi, S.Y.; Schrempp, F.

    1991-12-01

    We examine the potential of a future 500 GeV linear e + e - collider for probing anomalous WW γ and WW γγ couplings in the so-called γ(γ)model, corresponding to colliding γe and γγ beams from Compton backscattering of laser light. We consider in detail the 'minimal' set (k γ , λ γ ) of CP conserving anomalous couplings and present first results for the CP violating 'partner' couplings (anti K γ , anti l γ ) as well. The reactions under consideration are γe → Wν, γγ → W + W - and, as a reference, also e + e - → W + W - . We discuss the impact of both circular polarization of laser photons and polarized e(anti e) beams. Photon 'beams' due to classical Bremsstrahlung are also studied for comparison. We analyze in detail, how changes of the assumed machine parameters, cuts and systematic errors affect the sensitivity to the anomalous couplings. (orig.)

  5. Steady-State Anderson Accelerated Coupling of Lattice Boltzmann and Navier–Stokes Solvers

    KAUST Repository

    Atanasov, Atanas; Uekermann, Benjamin; Pachajoa Mejí a, Carlos; Bungartz, Hans-Joachim; Neumann, Philipp

    2016-01-01

    to the fullest extent and yields enhanced control to match the LB and NS degrees of freedom within the LBNS overlap layer. Designed for parallel Schwarz coupling, the Anderson acceleration allows for the simultaneous execution of both Lattice Boltzmann and Navier

  6. Quantification of plant cell coupling with three-dimensional photoactivation microscopy.

    Science.gov (United States)

    Liesche, J; Schulz, A

    2012-07-01

    Plant cells are directly connected by plasmodesmata that form channels through the cell wall and enable the intercellular movement of cytosolic solutes, membrane lipids and signalling molecules. Transport through plasmodesmata is regulated not only by a fixed size-exclusion limit, but also by physiological and pathological adaptation. To understand plant cell communication, carbon allocation and pathogen attack, the capacities for a specific molecule to pass a specific cell-wall interface is an essential parameter. So far, the degree of cell coupling was derived from frequency and diameter of plasmodesmata in relevant tissues as assessed by electron microscopy of fixed material. However, plasmodesmata functionality and capacity can only be determined in live material, not from electron microscopy, which is static and prone to fixation artefacts. Plasmodesmata functionality was a few times assessed using fluorescent tracers with diffusion properties similar to cytosolic solutes. Here, we used three-dimensional photoactivation microscopy to quantify plasmodesmata-mediated cell-wall permeability between living Cucurbita maxima leaf mesophyll cells with caged fluorescein as tracer. For the first time, all necessary functional and anatomical data were gathered for each individual cell from three-dimensional time series. This approach utilized a confocal microscope equipped with resonant scanner, which provides the high acquisition speed necessary to record optical sections of whole cells and offers time resolution high enough to follow the kinetics of photoactivation. The results were compared to two-dimensional measurements, which are shown to give a good estimate of cell coupling adequate for homogenous tissues. The two-dimensional approach is limited whenever tissues interfaces are studied that couple different cell types with diverse cell geometries. © 2011 The Authors Journal of Microscopy © 2011 Royal Microscopical Society.

  7. Collective spin correlations and entangled state dynamics in coupled quantum dots

    Science.gov (United States)

    Maslova, N. S.; Arseyev, P. I.; Mantsevich, V. N.

    2018-02-01

    Here we demonstrate that the dynamics of few-electron states in a correlated quantum-dot system coupled to an electronic reservoir is governed by the symmetry properties of the total system leading to the collective behavior of all the electrons. Time evolution of two-electron states in a correlated double quantum dot after coupling to the reservoir has been analyzed by means of kinetic equations for pseudoparticle occupation numbers with constraint on possible physical states. It was revealed that the absolute value of the spin correlation function and the degree of entanglement for two-electron states could considerably increase after coupling to the reservoir. The obtained results demonstrate the possibility of a controllable tuning of both the spin correlation function and the concurrence value in a coupled quantum-dot system by changing of the gate voltage applied to the barrier separating the dots.

  8. Interwell coupling effect in Si/SiGe quantum wells grown by ultra high vacuum chemical vapor deposition

    Directory of Open Access Journals (Sweden)

    Loh Ter-Hoe

    2007-01-01

    Full Text Available AbstractSi/Si0.66Ge0.34coupled quantum well (CQW structures with different barrier thickness of 40, 4 and 2 nm were grown on Si substrates using an ultra high vacuum chemical vapor deposition (UHV-CVD system. The samples were characterized using high resolution x-ray diffraction (HRXRD, cross-sectional transmission electron microscopy (XTEM and photoluminescence (PL spectroscopy. Blue shift in PL peak energy due to interwell coupling was observed in the CQWs following increase in the Si barrier thickness. The Si/SiGe heterostructure growth process and theoretical band structure model was validated by comparing the energy of the no-phonon peak calculated by the 6 + 2-bandk·pmethod with experimental PL data. Close agreement between theoretical calculations and experimental data was obtained.

  9. Coagulation-Fenton coupled treatment for ecotoxicity reduction in highly polluted industrial wastewater.

    Science.gov (United States)

    Perdigón-Melón, J A; Carbajo, J B; Petre, A L; Rosal, R; García-Calvo, E

    2010-09-15

    A coupled coagulation-Fenton process was applied for the treatment of cosmetic industry effluents. In a first step, FeSO(4) was used as coagulant and the non-precipitated Fe(2+) remaining in dissolution was used as catalyst in the further Fenton process. In the coagulation process a huge decrease in total organic carbon (TOC) was achieved, but the high concentration of phenol derivatives was not diminished. The decrease in TOC in the coagulation step significantly reduces the amount of H(2)O(2) required in the Fenton process for phenol depletion. The coupled process, using a H(2)O(2) dose of only 2 g l(-1), reduced TOC and total phenol to values lower than 40 and 0.10 mg l(-1), respectively. The short reaction period (less than 15 min) in TOC and phenol degradation bodes well for improving treatment in a continuous regime. The combination of both processes significantly reduced the ecotoxicity of raw effluent and markedly increased its biodegradability, thus allowing easier treatment by the conventional biological units in conventional sewage treatment plants (STPs). Copyright 2010 Elsevier B.V. All rights reserved.

  10. Magnetoelastic couplings in the distorted diamond-chain compound azurite

    Science.gov (United States)

    Cong, Pham Thanh; Wolf, Bernd; Manna, Rudra Sekhar; Tutsch, Ulrich; de Souza, Mariano; Brühl, Andreas; Lang, Michael

    2014-05-01

    We present results of ultrasonic measurements on a single crystal of the distorted diamond-chain compound azurite Cu3(CO3)2(OH)2. Pronounced elastic anomalies are observed in the temperature dependence of the longitudinal elastic mode c22 which can be assigned to the relevant magnetic interactions in the system and their couplings to the lattice degrees of freedom. From a semiquantitative analysis of the magnetic contribution to c22 the magnetoelastic coupling G =∂J2/∂ɛb can be estimated, where J2 is the intradimer coupling constant and ɛb the strain along the intrachain b axis. We find an exceptionally large coupling constant of |G |˜ 3650 K highlighting an extraordinarily strong sensitivity of J2 against changes of the b-axis lattice parameter. These results are complemented by measurements of the hydrostatic pressure dependence of J2 by means of thermal expansion and magnetic susceptibility measurements performed both at ambient and finite hydrostatic pressure. We propose that a structural peculiarity of this compound, in which Cu2O6 dimer units are incorporated in an unusually stretched manner, is responsible for the anomalously large magnetoelastic coupling.

  11. Investigation of a coupling model of coordination between urbanization and the environment.

    Science.gov (United States)

    Li, Yangfan; Li, Yi; Zhou, Yan; Shi, Yalou; Zhu, Xiaodong

    2012-05-15

    China's coastal cities are experiencing rapid urbanization, which has resulted in many challenges. This paper presents a comprehensive index system for assessment of the level of urbanization based on four aspects: demographic urbanization, economic urbanization, social urbanization and spatial urbanization. The developed index system also characterizes the environment based on three factors: environmental pressure, environmental level and environmental control. Furthermore, a coupling coordination degree model (CCDM) focusing on the degree of coordination between urbanization and the environment was established using panel data collected from 2000 to 2008 for Lianyungang, China. The results showed that: (1) the dynamic of coordination between urbanization and the environment showed a U-shaped curve, and both sub-systems evolved into a superior balance during rapid urbanization; (2) social urbanization and environmental control make the greatest contribution to the coupling system, indicating that they are the critical factors to consider when adjusting coordination development during decision-making; and (3) the two parameters (α-urbanization, β-environment) that have been widely used in previous studies had less of an effect on the coupling coordinated system than the other factors considered herein. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Electrospun N-doped Hierarchical Porous Carbon Nanofiber with Improved Graphitization Degree for High Performance Lithium Ion Capacitor.

    Science.gov (United States)

    Li, Baohua; Shi, Ruiying; Han, Cuiping; Xu, Xiaofu; Qing, Xianying; Xu, Lei; Li, Hongfei; Li, Junqin; Wong, Ching-Ping

    2018-05-14

    Lithium ion capacitor (LIC) has been regarded as a promising device to combine the merits of lithium ion batteries and supercapacitors, which can meet the requirements for both high energy and power density. The development of advanced electrode is the key. Herein, we demonstrate the bottom-up synthesis of activated carbon nanofiber (a-PANF) with hierarchical porous structure and high graphitization degree. Electrospinning is employed to prepare interconnected fiber network with macropores and ferric acetylacetonate is introduced as both mesopore creating agent and graphitic catalyst to increase the graphitization degree. Furthermore, chemical activation enlarges the specific surface area by producing rich micropores. Half cell evaluation of the as-prepared a-PANF displays a discharge capacity of 80 mAh g-1 at 0.1 A g-1 within 2~4.5 V and no capacity fading after 1000 cycles at 2 A g-1, which is significantly higher than conventional activated carbon. Furthermore, the as-assembled LIC with a-PANF cathode and Fe3O4 anode achieves a superior energy density of 124.6 Wh kg-1 at a specific power of 93.8 W kg-1, and remains 103.7 Wh kg-1 at 4687.5 W kg-1, demonstrating the promising application of a-PANF as potential electrode candidates for efficient energy storage systems. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Degree distribution in discrete case

    International Nuclear Information System (INIS)

    Wang, Li-Na; Chen, Bin; Yan, Zai-Zai

    2011-01-01

    Vertex degree of many network models and real-life networks is limited to non-negative integer. By means of measure and integral, the relation of the degree distribution and the cumulative degree distribution in discrete case is analyzed. The degree distribution, obtained by the differential of its cumulative, is only suitable for continuous case or discrete case with constant degree change. When degree change is not a constant but proportional to degree itself, power-law degree distribution and its cumulative have the same exponent and the mean value is finite for power-law exponent greater than 1. -- Highlights: → Degree change is the crux for using the cumulative degree distribution method. → It suits for discrete case with constant degree change. → If degree change is proportional to degree, power-law degree distribution and its cumulative have the same exponent. → In addition, the mean value is finite for power-law exponent greater than 1.

  14. Schematic large-dimension coupled-channel study of strong inelastic excitations to high-lying states in colliding nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Kamimura, M. [Rijksuniversiteit Groningen (Netherlands). Kernfysisch Versneller Inst.; Nakano, M.; Yahiro, M.; Ikegami, H.; Muraoka, M. [eds.

    1980-01-01

    A mechanism of the strong inelastic excitation of colliding nuclei (e.g. deep inelastic heavy-ion collision) was studied in a schematic way based on a coupled channel (CC) framework. The purpose of this work is to see the gross behavior of the inelastic excitation strength versus epsilon (i.e. energy spectrum) for the assumed specific types of CC potentials between a large number of inelastic channels. Schematic large dimension CC calculation was considered rather than small-dimension CC calculation. The coupled N + 1 equations can be reduced to uncoupled N + 1 equations through the wellknown unitary transformation. An interesting case is that there exists strong channel independent coupling between any pair of the channels, all of which are almost degenerate in internal energy as compared with incoming c.m. energy. It was found that inelastic scattering hardly occurred while the collision was almost confined to the elastic component. The numerical calculation of S-matrix was carried out. Other cases, such as zero CC potential, the coupling between inelastic channel and entrance channel, and the case that the thickness of the coupling was changed, were investigated. As the results of the present study, it can be said that this CC coupling model may be useful for discussing continuum-continuum interactions in a breakup reaction by simulating the continuum states with many channels made discrete.

  15. Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods

    International Nuclear Information System (INIS)

    Mai, Sebastian; Marquetand, Philipp; González, Leticia; Müller, Thomas; Plasser, Felix; Lischka, Hans

    2014-01-01

    An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the COLUMBUS quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbit coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations

  16. Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods

    Energy Technology Data Exchange (ETDEWEB)

    Mai, Sebastian; Marquetand, Philipp; González, Leticia [Institute of Theoretical Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna (Austria); Müller, Thomas, E-mail: th.mueller@fz-juelich.de [Institute for Advanced Simulation, Jülich Supercomputing Centre, Forschungszentrum Jülich, 52425 Jülich (Germany); Plasser, Felix [Interdisciplinary Center for Scientific Computing, University of Heidelberg, Im Neuenheimer Feld 368, 69120 Heidelberg (Germany); Lischka, Hans [Institute of Theoretical Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna (Austria); Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061 (United States)

    2014-08-21

    An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the COLUMBUS quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbit coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations.

  17. Panel report on coupled thermo-mechanical-hydro-chemical processes associated with a nuclear waste repository

    International Nuclear Information System (INIS)

    Tsang, C.F.; Mangold, D.C.

    1984-07-01

    Four basic physical processes, thermal, hydrological, mechanical and chemical, are likely to occur in 11 different types of coupling during the service life of an underground nuclear waste repository. A great number of coupled processes with various degrees of importance for geological repositories were identified and arranged into these 11 types. A qualitative description of these processes and a tentative evaluation of their significance and the degree of uncertainty in prediction is given. Suggestions for methods of investigation generally include, besides theoretical work, laboratory and large scale field testing. Great efforts of a multidisciplinary nature are needed to elucidate details of several coupled processes under different temperature conditions in different geological formations. It was suggested that by limiting the maximum temperature to 100 0 C in the backfill and in the host rock during the whole service life of the repository the uncertainties in prediction of long-term repository behavior might be considerably reduced

  18. Panel report on coupled thermo-mechanical-hydro-chemical processes associated with a nuclear waste repository

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, C.F.; Mangold, D.C. (eds.)

    1984-07-01

    Four basic physical processes, thermal, hydrological, mechanical and chemical, are likely to occur in 11 different types of coupling during the service life of an underground nuclear waste repository. A great number of coupled processes with various degrees of importance for geological repositories were identified and arranged into these 11 types. A qualitative description of these processes and a tentative evaluation of their significance and the degree of uncertainty in prediction is given. Suggestions for methods of investigation generally include, besides theoretical work, laboratory and large scale field testing. Great efforts of a multidisciplinary nature are needed to elucidate details of several coupled processes under different temperature conditions in different geological formations. It was suggested that by limiting the maximum temperature to 100{sup 0}C in the backfill and in the host rock during the whole service life of the repository the uncertainties in prediction of long-term repository behavior might be considerably reduced.

  19. Copula-based modeling of degree-correlated networks

    International Nuclear Information System (INIS)

    Raschke, Mathias; Schläpfer, Markus; Trantopoulos, Konstantinos

    2014-01-01

    Dynamical processes on complex networks such as information exchange, innovation diffusion, cascades in financial networks or epidemic spreading are highly affected by their underlying topologies as characterized by, for instance, degree–degree correlations. Here, we introduce the concept of copulas in order to generate random networks with an arbitrary degree distribution and a rich a priori degree–degree correlation (or ‘association’) structure. The accuracy of the proposed formalism and corresponding algorithm is numerically confirmed, while the method is tested on a real-world network of yeast protein–protein interactions. The derived network ensembles can be systematically deployed as proper null models, in order to unfold the complex interplay between the topology of real-world networks and the dynamics on top of them. (paper)

  20. Coupling technology for dual-purpose nuclear-desalting plants

    International Nuclear Information System (INIS)

    Jones, J.E. Jr.; Anderson, T.D.; Reed, S.A.

    1976-11-01

    Although the basic technology for the various components of nuclear dual-purpose plants is reasonably well developed, the techniques of coupling the elements together to form a reliable, economical system that will satisfy the diverse operating requirements are not well established. The purpose of the study reported is to examine the technical, economic, and safety considerations in coupling nuclear power plants with distillation units to form a dual-purpose power and water distillation plant. The basic coupling arrangement required to provide a large-scale dual-purpose water plant is to supply steam to the water plant from the exhaust of a back-pressure turbine. The principal component at the interface that may require major research and development is the back-pressure turbine. To satisfy the operational requirements, two major auxiliary systems will be needed. These are: (1) a prime-steam bypass system, and (2) auxiliary condensers. These systems will provide a degree of independence between water and power production and can be justified economically

  1. LO-phonon and plasmon coupling in neutron-transmutation-doped GaAs

    International Nuclear Information System (INIS)

    Kuriyama, K.; Sakai, K.; Okada, M.

    1996-01-01

    Coupling between the longitudinal-optic (LO) phonon mode and the longitudinal plasma mode in neutron-transmutation-doped (NTD) semi-insulating GaAs was studied using Raman-scattering spectroscopy and a Fourier-transform infrared spectrometer. When the electron concentration due to the activation of NTD impurities (Ge Ga and Se As ) approaches ∼8x10 16 cm -3 , the LO-phonon endash plasmon coupling is observed. This behavior is consistent with the free-electron absorption due to the activation of NTD impurities in samples annealed above 600 degree C. copyright 1996 The American Physical Society

  2. Design Configurations and Coupling High Temperature Gas-Cooled Reactor and Hydrogen Plant

    International Nuclear Information System (INIS)

    Chang H. Oh; Eung Soo Kim; Steven Sherman

    2008-01-01

    The US Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the high-temperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power plant. An intermediate heat transport loop will be required to separate the operations and safety functions of the nuclear and hydrogen plants. A next generation high-temperature reactor could be envisioned as a single-purpose facility that produces hydrogen or a dual-purpose facility that produces hydrogen and electricity. Early plants, such as the proposed Next Generation Nuclear Plant (NGNP), may be dual-purpose facilities that demonstrate both hydrogen and efficient electrical generation. Later plants could be single-purpose facilities. At this stage of development, both single- and dual-purpose facilities need to be understood

  3. Quasi-monoenergetic neutron energy spectra for 246 and 389 MeV (7)Li(p,n) reactions at angles from 0 degrees to 300 degrees

    CERN Document Server

    Iwamoto, Y; Nakamura, T; Nakashima, H; Mares, V; Itoga, T; Matsumoto, T; Nakane, Y; Feldbaumer, E; Jaegerhofer, L; Pioch, C; Tamii, A; Satoh, D; Masuda, A; Sato, T; Iwase, H; Yashima, H; Nishiyama, J; Hagiwara, M; Hatanaka, K; Sakamoto, Y

    2011-01-01

    The authors measured the neutron energy spectra of a quasi-monoenergetic (7)Li(p,n) neutron source with 246 and 389 MeV protons set at seven angles (0 degrees, 2.5 degrees, 5 degrees, 10 degrees, 15 degrees, 20 degrees and 30 degrees), using a time-of-flight (TOF) method employing organic scintillators NE213 at the Research Center for Nuclear Physics (RCNP) of Osaka University. The energy spectra of the source neutrons were precisely deduced down to 2 MeV at 0 degrees and 10 MeV at other angles. The cross-sections of the peak neutron production reaction at 0 degrees were on the 35-40 mb line of other experimental data, and the peak neutron angular distribution agreed well with the Taddeucci formula. Neutron energy spectra below 100 MeV at all angles were comparable, but the shapes of the continuum above 150 MeV changed considerably with the angle. In order to consider the correction required to derive the response in the peak region from the measured total response for high-energy neutron monitors such as DAR...

  4. Photogenerated Exciton Dissociation in Highly Coupled Lead Salt Nanocrystal Assemblies

    KAUST Repository

    Choi, Joshua J.; Luria, Justin; Hyun, Byung-Ryool; Bartnik, Adam C.; Sun, Liangfeng; Lim, Yee-Fun; Marohn, John A.; Wise, Frank W.; Hanrath, Tobias

    2010-01-01

    Internanocrystal coupling induced excitons dissociation in lead salt nanocrystal assemblies is investigated. By combining transient photoluminescence spectroscopy, grazing incidence small-angle X-ray scattering, and time-resolved electric force microscopy, we show that excitons can dissociate, without the aid of an external bias or chemical potential gradient, via tunneling through a potential barrier when the coupling energy is comparable to the exciton binding energy. Our results have important implications for the design of nanocrystal-based optoelectronic devices. © 2010 American Chemical Society.

  5. Photogenerated Exciton Dissociation in Highly Coupled Lead Salt Nanocrystal Assemblies

    KAUST Repository

    Choi, Joshua J.

    2010-05-12

    Internanocrystal coupling induced excitons dissociation in lead salt nanocrystal assemblies is investigated. By combining transient photoluminescence spectroscopy, grazing incidence small-angle X-ray scattering, and time-resolved electric force microscopy, we show that excitons can dissociate, without the aid of an external bias or chemical potential gradient, via tunneling through a potential barrier when the coupling energy is comparable to the exciton binding energy. Our results have important implications for the design of nanocrystal-based optoelectronic devices. © 2010 American Chemical Society.

  6. Resonance tuning due to Coulomb interaction in strong near-field coupled metamaterials

    International Nuclear Information System (INIS)

    Roy Chowdhury, Dibakar; Xu, Ningning; Zhang, Weili; Singh, Ranjan

    2015-01-01

    Coulomb's law is one of the most fundamental laws of physics that describes the electrostatic interaction between two like or unlike point charges. Here, we experimentally observe a strong effect of Coulomb interaction in tightly coupled terahertz metamaterials where the split-ring resonator dimers in a unit cell are coupled through their near fields across the capacitive split gaps. Using a simple analytical model, we evaluated the Coulomb parameter that switched its sign from negative to positive values indicating the transition in the nature of Coulomb force from being repulsive to attractive depending upon the near field coupling between the split ring resonators. Apart from showing interesting effects in the strong coupling regime between meta-atoms, Coulomb interaction also allows an additional degree of freedom to achieve frequency tunable dynamic metamaterials

  7. High-degree atrioventricular block complicating ST-segment elevation myocardial infarction in the era of primary percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Gang, Uffe Jakob Ortved; Hvelplund, Anders; Pedersen, Sune

    2012-01-01

    Primary percutaneous coronary intervention (pPCI) has replaced thrombolysis as treatment-of-choice for ST-segment elevation myocardial infarction (STEMI). However, the incidence and prognostic significance of high-degree atrioventricular block (HAVB) in STEMI patients in the pPCI era has been only...... sparsely investigated. The objective of this study was to assess the incidence, predictors and prognostic significance of HAVB in STEMI patients treated with pPCI....

  8. First example of a high-level correlated calculation of the indirect spin-spin coupling constants involving tellurium

    DEFF Research Database (Denmark)

    Rusakov, Yury Yu; Krivdin, Leonid B.; Østerstrøm, Freja From

    2013-01-01

    This paper documents a very first example of a high-level correlated calculation of spin-spin coupling constants involving tellurium taking into account relativistic effects, vibrational corrections and solvent effects for the medium sized organotellurium molecules. The 125Te-1H spin-spin coupling...... constants of tellurophene and divinyl telluride were calculated at the SOPPA and DFT levels in a good agreement with experiment. A new full-electron basis set av3z-J for tellurium derived from the "relativistic" Dyall's basis set, dyall.av3z, and specifically optimized for the correlated calculations...... of spin-spin coupling constants involving tellurium, was developed. The SOPPA methods show much better performance as compared to 15 those of DFT, if relativistic effects calculated within the ZORA scheme are taken into account. Vibrational and solvent corrections are next to negligible, while...

  9. Creation of quantum entanglement with two separate diamond nitrogen vacancy centers coupled to a photonic molecule

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Siping [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics and Electronic Engineering, Hubei University of Arts and Science, Xiangyang 441053 (China); Yu, Rong, E-mail: rong-yu2013@163.com [School of Science, Hubei Province Key Laboratory of Intelligent Robot, Wuhan Institute of Technology, Wuhan 430073 (China); Li, Jiahua, E-mail: huajia-li@163.com [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Key Laboratory of Fundamental Physical Quantities Measurement of Ministry of Education, Wuhan 430074 (China); Wu, Ying [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2013-12-28

    We explore the entanglement generation and the corresponding dynamics between two separate nitrogen-vacancy (NV) centers in diamond nanocrystal coupled to a photonic molecule consisting of a pair of coupled photonic crystal (PC) cavities. By calculating the entanglement concurrence with readily available experimental parameters, it is found that the entanglement degree strongly depends on the cavity-cavity hopping strength and the NV-center-cavity detuning. High concurrence peak and long-lived entanglement plateau can be achieved by properly adjusting practical system parameters. Meanwhile, we also discuss the influence of the coupling strength between the NV centers and the cavity modes on the behavior of the concurrence. Such a PC-NV system can be employed for quantum entanglement generation and represents a building block for an integrated nanophotonic network in a solid-state cavity quantum electrodynamics platform. In addition, the present theory can also be applied to other similar systems, such as two single quantum emitters positioned close to a microtoroidal resonator with the whispering-gallery-mode fields propagating inside the resonator.

  10. Anterior Thalamic High Frequency Band Activity Is Coupled with Theta Oscillations at Rest

    Directory of Open Access Journals (Sweden)

    Catherine M. Sweeney-Reed

    2017-07-01

    Full Text Available Cross-frequency coupling (CFC between slow and fast brain rhythms, in the form of phase–amplitude coupling (PAC, is proposed to enable the coordination of neural oscillatory activity required for cognitive processing. PAC has been identified in the neocortex and mesial temporal regions, varying according to the cognitive task being performed and also at rest. PAC has also been observed in the anterior thalamic nucleus (ATN during memory processing. The thalamus is active during the resting state and has been proposed to be involved in switching between task-free cognitive states such as rest, in which attention is internally-focused, and externally-focused cognitive states, in which an individual engages with environmental stimuli. It is unknown whether PAC is an ongoing phenomenon during the resting state in the ATN, which is modulated during different cognitive states, or whether it only arises during the performance of specific tasks. We analyzed electrophysiological recordings of ATN activity during rest from seven patients who received thalamic electrodes implanted for treatment of pharmacoresistant focal epilepsy. PAC was identified between theta (4–6 Hz phase and high frequency band (80–150 Hz amplitude during rest in all seven patients, which diminished during engagement in tasks involving an external focus of attention. The findings are consistent with the proposal that theta–gamma coupling in the ATN is an ongoing phenomenon, which is modulated by task performance.

  11. Coupled urbanization and agricultural ecosystem services in Guanzhong-Tianshui Economic Zone.

    Science.gov (United States)

    Zhou, Z X; Li, J; Zhang, W

    2016-08-01

    Ecosystems offer material and environmental support for human habitation and development in those areas of the earth where people choose to live. However, urbanization is an inexorable trend of human social development and threatens the health of those ecosystems inhabited by humans. This study calculates the values of NPP (net primary productivity), carbon sequestration, water interception, soil conservation, and agricultural production in the Guanzhong-Tianshui Economic Zone. At the same time, we combined DMSP/OLS (Defense Meteorological Satellite Program Operational Line Scanner) night lights remote sensing data and statistical data to analyze the level of urbanization. Quantitative analysis was performed on the interactions between the ecosystem service functions and urbanization based on the calculations of their coupled coordination degrees. The results were the following: (1) The values of NPP, carbon sequestration, and agricultural production showed a trend of increase. However, water interception decreased before increasing, while soil conservation showed the reverse trend; (2) Urbanization levels in the Guanzhong-Tianshui Economic Zone for the last 10 years have proceeded at a fast pace with comprehensive promotion; and (3) Coupled and coupled coordination degrees between urbanization and ecosystem services show increasing trends. This research can provide a theoretical basis for the region's rapid economic development in the balance.

  12. Interplay of mesonic and baryonic degrees of freedom in quark matter

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Naseemuddin

    2015-11-03

    In this work we study the influence of mesonic and baryonic fluctuations on the phase diagram of quark matter with two flavors. By examining the hadronization process and related techniques, we derive effective low-energy models, where the gluons are integrated out. To be able to compare our model calculations with lattice results at finite chemical potential, we investigate a QCD-like theory with two colors, where the sign-problem is absent. To this end we introduce a quark-meson-diquark model, where the bosonic diquarks play the role of colorless, baryonic degrees of freedom competing with the mesons. To access the phase diagram and determine the phases of chiral and diquark condensation, we employ a functional renormalization group approach allowing for a systematic non-perturbative truncation scheme. Interesting phenomena arise that are known from condensed matter physics, as the BEC-BSC crossover and a phase of condensation within domains. We explore the impact of running wave function renormalizations and Yukawa couplings for the quarks and the boson fields on top of the scale dependence of the effective potential. In the course of this we discuss the Silver Blaze property and its realization within a functional approach. In parallel, we formulate a quark-meson-diquark-baryon model for physical QCD as a low-energy effective theory for baryonic matter at high density, and discuss the relevance of the diquark and baryon degrees of freedom. In this sense, we compute a phase diagram for QCD from functional methods, including a color superconducting phase.

  13. Stochastic substitute for coupled rate equations in the modeling of highly ionized transient plasmas

    International Nuclear Information System (INIS)

    Eliezer, S.; Falquina, R.; Minguez, E.

    1994-01-01

    Plasmas produced by intense laser pulses incident on solid targets often do not satisfy the conditions for local thermodynamic equilibrium, and so cannot be modeled by transport equations relying on equations of state. A proper description involves an excessively large number of coupled rate equations connecting many quantum states of numerous species having different degrees of ionization. Here we pursue a recent suggestion to model the plasma by a few dominant states perturbed by a stochastic driving force. The driving force is taken to be a Poisson impulse process, giving a Langevin equation which is equivalent to a Fokker-Planck equation for the probability density governing the distribution of electron density. An approximate solution to the Langevin equation permits calculation of the characteristic relaxation rate. An exact stationary solution to the Fokker-Planck equation is given as a function of the strength of the stochastic driving force. This stationary solution is used, along with a Laplace transform, to convert the Fokker-Planck equation to one of Schroedinger type. We consider using the classical Hamiltonian formalism and the WKB method to obtain the time-dependent solution

  14. Effect of wire size on maxillary arch force/couple systems for a simulated high canine malocclusion.

    Science.gov (United States)

    Major, Paul W; Toogood, Roger W; Badawi, Hisham M; Carey, Jason P; Seru, Surbhi

    2014-12-01

    To better understand the effects of copper nickel titanium (CuNiTi) archwire size on bracket-archwire mechanics through the analysis of force/couple distributions along the maxillary arch. The hypothesis is that wire size is linearly related to the forces and moments produced along the arch. An Orthodontic Simulator was utilized to study a simplified high canine malocclusion. Force/couple distributions produced by passive and elastic ligation using two wire sizes (Damon 0.014 and 0.018 inch) measured with a sample size of 144. The distribution and variation in force/couple loading around the arch is a complicated function of wire size. The use of a thicker wire increases the force/couple magnitudes regardless of ligation method. Owing to the non-linear material behaviour of CuNiTi, this increase is less than would occur based on linear theory as would apply for stainless steel wires. The results demonstrate that an increase in wire size does not result in a proportional increase of applied force/moment. This discrepancy is explained in terms of the non-linear properties of CuNiTi wires. This non-proportional force response in relation to increased wire size warrants careful consideration when selecting wires in a clinical setting. © 2014 British Orthodontic Society.

  15. The role of flavon cross couplings in leptonic flavour mixing

    Energy Technology Data Exchange (ETDEWEB)

    Pascoli, Silvia [Institute for Particle Physics Phenomenology, Department of Physics, Durham University,South Road, Durham DH1 3LE (United Kingdom); Zhou, Ye-Ling [Institute for Particle Physics Phenomenology, Department of Physics, Durham University,South Road, Durham DH1 3LE (United Kingdom); Center for High Energy Physics, Peking University,No. 5 Yiheyuan Road, Beijing 100080 (China)

    2016-06-13

    In models with discrete flavour symmetries, flavons are critical to realise specific flavour structures. Leptonic flavour mixing originates from the misalignment of flavon vacuum expectation values which respect different residual symmetries in the charged lepton and neutrino sectors. Flavon cross couplings are usually forbidden, in order to protect these symmetries. Contrary to this approach, we show that cross couplings can play a key role and give raise to necessary corrections to flavour-mixing patterns, including a non-zero value for the reactor angle and CP violation. For definiteness, we present two models based on A{sub 4}. In the first model, all flavons are assumed to be real or pseudo-real, with 7 real degrees of freedom in the flavon sector in total. A sizable reactor angle associated with nearly maximal CP violation is achieved, and, as both originate from the same cross coupling, a sum rule results with a precise prediction for the value of the Dirac CP-violating phase. In the second model, the flavons are taken to be complex scalars, which can be connected with supersymmetric models and multi-Higgs models. The complexity properties of flavons provide new sources for generating the reactor angle. Models in this new approach introduce very few degrees of freedom beyond the Standard Model and can be more economical than those in the framework of extra dimension or supersymmetry.

  16. Planar real polynomial differential systems of degree n > 3 having a weak focus of high order

    International Nuclear Information System (INIS)

    Llibre, J.; Rabanal, R.

    2008-06-01

    We construct planar polynomial differential systems of even (respectively odd) degree n > 3, of the form linear plus a nonlinear homogeneous part of degree n having a weak focus of order n 2 -1 (respectively (n 2 -1)/2 ) at the origin. As far as we know this provides the highest order known until now for a weak focus of a polynomial differential system of arbitrary degree n. (author)

  17. Ultrafast Coulomb-Induced Intervalley Coupling in Atomically Thin WS2.

    Science.gov (United States)

    Schmidt, Robert; Berghäuser, Gunnar; Schneider, Robert; Selig, Malte; Tonndorf, Philipp; Malić, Ermin; Knorr, Andreas; Michaelis de Vasconcellos, Steffen; Bratschitsch, Rudolf

    2016-05-11

    Monolayers of semiconducting transition metal dichalcogenides hold the promise for a new paradigm in electronics by exploiting the valley degree of freedom in addition to charge and spin. For MoS2, WS2, and WSe2, valley polarization can be conveniently initialized and read out by circularly polarized light. However, the underlying microscopic processes governing valley polarization in these atomically thin equivalents of graphene are still not fully understood. Here, we present a joint experiment-theory study on the ultrafast time-resolved intervalley dynamics in monolayer WS2. Based on a microscopic theory, we reveal the many-particle mechanisms behind the observed spectral features. We show that Coulomb-induced intervalley coupling explains the immediate and prominent pump-probe signal in the unpumped valley and the seemingly low valley polarization degrees typically observed in pump-probe measurements compared to photoluminescence studies. The gained insights are also applicable to other light-emitting monolayer transition metal dichalcogenides, such as MoS2 and WSe2, where the Coulomb-induced intervalley coupling also determines the initial carrier dynamics.

  18. Linear analysis of coupled lattices

    Directory of Open Access Journals (Sweden)

    D. Sagan

    1999-07-01

    Full Text Available A formalism for describing the coupled two-dimensional motion of high energy particle beams in a storage ring is developed and extended to circumstances where the coupling is very strong, such as for the Möbius twist accelerator.

  19. The infinite range Heisenberg model and high temperature superconductivity

    Science.gov (United States)

    Tahir-Kheli, Jamil

    1992-01-01

    The thesis deals with the theory of high temperature superconductivity from the standpoint of three-band Hubbard models.Chapter 1 of the thesis proposes a strongly coupled variational wavefunction that has the three-spin system of an oxygen hole and its two neighboring copper spins in a doublet and the background Cu spins in an eigenstate of the infinite range antiferromagnet. This wavefunction is expected to be a good "zeroth order" wavefunction in the superconducting regime of dopings. The three-spin polaron is stabilized by the hopping terms rather than the copper-oxygen antiferromagnetic coupling Jpd. Considering the effect of the copper-copper antiferromagnetic coupling Jdd, we show that the three-spin polaron cannot be pure Emery (Dg), but must have a non-negligible amount of doublet-u (Du) character for hopping stabilization. Finally, an estimate is made for the magnitude of the attractive coupling of oxygen holes.Chapter 2 presents an exact solution to a strongly coupled Hamiltonian for the motion of oxygen holes in a 1-D Cu-O lattice. The Hamiltonian separates into two pieces: one for the spin degrees of freedom of the copper and oxygen holes, and the other for the charge degrees of freedom of the oxygen holes. The spinon part becomes the Heisenberg antiferromagnet in 1-D that is soluble by the Bethe Ansatz. The holon piece is also soluble by a Bethe Ansatz with simple algebraic relations for the phase shifts.Finally, we show that the nearest neighbor Cu-Cu spin correlation increases linearly with doping and becomes positive at x [...] 0.70.

  20. Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes

    International Nuclear Information System (INIS)

    Edwin A. Harvego; Michael G. McKellar; James E. O'Brien; J. Stephen Herring

    2007-01-01

    High Temperature Electrolysis (HTE), when coupled to an advanced nuclear reactor capable of operating at reactor outlet temperatures of 800 C to 950 C, has the potential to efficiently produce the large quantities of hydrogen needed to meet future energy and transportation needs. To evaluate the potential benefits of nuclear-driven hydrogen production, the UniSim process analysis software was used to evaluate different reactor concepts coupled to a reference HTE process design concept. The reference HTE concept included an Intermediate Heat Exchanger and intermediate helium loop to separate the reactor primary system from the HTE process loops and additional heat exchangers to transfer reactor heat from the intermediate loop to the HTE process loops. The two process loops consisted of the water/steam loop feeding the cathode side of a HTE electrolysis stack, and the steam or air sweep loop used to remove oxygen from the anode side. The UniSim model of the process loops included pumps to circulate the working fluids and heat exchangers to recover heat from the oxygen and hydrogen product streams to improve the overall hydrogen production efficiencies. The reference HTE process loop model was coupled to separate UniSim models developed for three different advanced reactor concepts (a high-temperature helium cooled reactor concept and two different supercritical CO2 reactor concepts). Sensitivity studies were then performed to evaluate the affect of reactor outlet temperature on the power cycle efficiency and overall hydrogen production efficiency for each of the reactor power cycles. The results of these sensitivity studies showed that overall power cycle and hydrogen production efficiencies increased with reactor outlet temperature, but the power cycle producing the highest efficiencies varied depending on the temperature range considered

  1. A stochastic six-degree-of-freedom flight simulator for passively controlled high power rockets

    OpenAIRE

    Box, Simon; Bishop, Christopher M.; Hunt, Hugh

    2011-01-01

    This paper presents a method for simulating the flight of a passively controlled rocket in six degrees of freedom, and the descent under parachute in three degrees of freedom, Also presented is a method for modelling the uncertainty in both the rocket dynamics and the atmospheric conditions using stochastic parameters and the Monte-Carlo method. Included within this we present a method for quantifying the uncertainty in the atmospheric conditions using historical atmospheric data. The core si...

  2. Aeroelastic response and stability of tiltrotors with elastically-coupled composite rotor blades. Ph.D. Thesis

    Science.gov (United States)

    Nixon, Mark W.

    1993-01-01

    There is a potential for improving the performance and aeroelastic stability of tiltrotors through the use of elastically-coupled composite rotor blades. To study the characteristics of tiltrotors with these types of rotor blades it is necessary to formulate a new analysis which has the capabilities of modeling both a tiltrotor configuration and an anisotropic rotor blade. Background for these formulations is established in two preliminary investigations. In the first, the influence of several system design parameters on tiltrotor aeroelastic stability is examined for the high-speed axial flight mode using a newly-developed rigid-blade analysis with an elastic wing finite element model. The second preliminary investigation addresses the accuracy of using a one-dimensional beam analysis to predict frequencies of elastically-coupled highly-twisted rotor blades. Important aspects of the new aeroelastic formulations are the inclusion of a large steady pylon angle which controls tilt of the rotor system with respect to the airflow, the inclusion of elastic pitch-lag coupling terms related to rotor precone, the inclusion of hub-related degrees of freedom which enable modeling of a gimballed rotor system and engine drive-train dynamics, and additional elastic coupling terms which enable modeling of the anisotropic features for both the rotor blades and the tiltrotor wing. Accuracy of the new tiltrotor analysis is demonstrated by a comparison of the results produced for a baseline case with analytical and experimental results reported in the open literature. Two investigations of elastically tailored blades on a baseline tiltrotor are then conducted. One investigation shows that elastic bending-twist coupling of the rotor blade is a very effective means for increasing the flutter velocity of a tiltrotor, and the magnitude of coupling required does not have an adverse effect on performance or blade loads. The second investigation shows that passive blade twist control via

  3. A Coupled Resonator for Highly Tunable and Amplified Mixer/Filter

    KAUST Repository

    Ilyas, Saad; Jaber, Nizar; Younis, Mohammad I.

    2017-01-01

    We present an H-shaped resonator made of two clamped-clamped microbeams mechanically coupled at the middle with a strong coupler to achieve, in a single device, mechanical amplification of the response signal, filtering, and frequency conversion simultaneously. Using mechanical amplification combined with combination resonances generated from a mixed-frequency excitation, a wideband tunable filter, and a simultaneous frequency up and down convertors at multiple bands is demonstrated. The proposed coupled structure, when combined with the easy-to-implement technique of frequency mixing, is promising for applications in an RF chain.

  4. A Coupled Resonator for Highly Tunable and Amplified Mixer/Filter

    KAUST Repository

    Ilyas, Saad

    2017-04-25

    We present an H-shaped resonator made of two clamped-clamped microbeams mechanically coupled at the middle with a strong coupler to achieve, in a single device, mechanical amplification of the response signal, filtering, and frequency conversion simultaneously. Using mechanical amplification combined with combination resonances generated from a mixed-frequency excitation, a wideband tunable filter, and a simultaneous frequency up and down convertors at multiple bands is demonstrated. The proposed coupled structure, when combined with the easy-to-implement technique of frequency mixing, is promising for applications in an RF chain.

  5. Highly enantioselective catalytic cross-dehydrogenative coupling of N-carbamoyl tetrahydroisoquinolines and terminal alkynes.

    Science.gov (United States)

    Sun, Shutao; Li, Chengkun; Floreancig, Paul E; Lou, Hongxiang; Liu, Lei

    2015-04-03

    The first catalytic asymmetric cross-dehydrogenative coupling of cyclic carbamates and terminal alkynes has been established. The reaction features high enantiocontrol and excellent functional group tolerance and displays a wide range of structurally and electronically diverse carbamates as well as terminal alkynes. N-Acyl hemiaminals were identified as the reactive intermediates through preliminary control experiments. Employing readily removable carbamates as substrates rather than traditionally adopted N-aryl amines allows applications in complex molecule synthesis and therefore advances the C-H functionalization strategy to a synthetically useful level.

  6. Characterization of water absorption by CFRP using air-coupled ultrasonic testing

    International Nuclear Information System (INIS)

    Lee, Joo Min; Lee, Joo Sung; Park, Ik Keun; Kim, Yong Kwon

    2014-01-01

    Carbon-fiber-reinforced plastic (CFRP) composites are increasingly being used in a variety of industry applications, such as aircraft, automobiles, and ships because of their high specific stiffness and high specific strength. Aircraft are exposed to high temperatures and high humidity for a long duration during flights. CFRP materials of the aircraft can absorb water, which could decrease the adhesion strength of these materials and cause their volumes to change with variation in internal stress. Therefore, it is necessary to estimate the characteristics of CFRP composites under actual conditions from the viewpoint of aircraft safety. In this study air-coupled ultrasonic testing (ACUT) was applied to the evaluation of water absorption properties of CFRP composites. CFRP specimens were fabricated and immersed in distilled water at 75 degree C for 30, 60, and 120 days, after which their ultrasonic images were obtained by ACUT. The water absorption properties were determined by quantitatively analyzing the changes in ultrasonic signals. Further, shear strength was applied to the specimens to verify the changes in their mechanical properties for water absorption.

  7. Characterization of water absorption by CFRP using air-coupled ultrasonic testing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo Min; Lee, Joo Sung; Park, Ik Keun [Seoul National University of Science and Technology, Seoul (Korea, Republic of); Kim, Yong Kwon [Technology Research and Development Institute, KEPCO Plant Service and Engineering Co., Ltd, Naju (Korea, Republic of)

    2014-04-15

    Carbon-fiber-reinforced plastic (CFRP) composites are increasingly being used in a variety of industry applications, such as aircraft, automobiles, and ships because of their high specific stiffness and high specific strength. Aircraft are exposed to high temperatures and high humidity for a long duration during flights. CFRP materials of the aircraft can absorb water, which could decrease the adhesion strength of these materials and cause their volumes to change with variation in internal stress. Therefore, it is necessary to estimate the characteristics of CFRP composites under actual conditions from the viewpoint of aircraft safety. In this study air-coupled ultrasonic testing (ACUT) was applied to the evaluation of water absorption properties of CFRP composites. CFRP specimens were fabricated and immersed in distilled water at 75 degree C for 30, 60, and 120 days, after which their ultrasonic images were obtained by ACUT. The water absorption properties were determined by quantitatively analyzing the changes in ultrasonic signals. Further, shear strength was applied to the specimens to verify the changes in their mechanical properties for water absorption.

  8. Inflationary models with non-minimally derivative coupling

    International Nuclear Information System (INIS)

    Yang, Nan; Fei, Qin; Gong, Yungui; Gao, Qing

    2016-01-01

    We derive the general formulae for the scalar and tensor spectral tilts to the second order for the inflationary models with non-minimally derivative coupling without taking the high friction limit. The non-minimally kinetic coupling to Einstein tensor brings the energy scale in the inflationary models down to be sub-Planckian. In the high friction limit, the Lyth bound is modified with an extra suppression factor, so that the field excursion of the inflaton is sub-Planckian. The inflationary models with non-minimally derivative coupling are more consistent with observations in the high friction limit. In particular, with the help of the non-minimally derivative coupling, the quartic power law potential is consistent with the observational constraint at 95% CL. (paper)

  9. Microscopic theory of the Coulomb based exchange coupling in magnetic tunnel junctions.

    Science.gov (United States)

    Udalov, O G; Beloborodov, I S

    2017-05-04

    We study interlayer exchange coupling based on the many-body Coulomb interaction between conduction electrons in magnetic tunnel junction. This mechanism complements the known interaction between magnetic layers based on virtual electron hopping (or spin currents). We find that these two mechanisms have different behavior on system parameters. The Coulomb based coupling may exceed the hopping based exchange. We show that the Coulomb based exchange interaction, in contrast to the hopping based coupling, depends strongly on the dielectric constant of the insulating layer. The dependence of the interlayer exchange interaction on the dielectric properties of the insulating layer in magnetic tunnel junction is similar to magneto-electric effect where electric and magnetic degrees of freedom are coupled. We calculate the interlayer coupling as a function of temperature and electric field for magnetic tunnel junction with ferroelectric layer and show that the exchange interaction between magnetic leads has a sharp decrease in the vicinity of the ferroelectric phase transition and varies strongly with external electric field.

  10. The πNN coupling from high precision np charge exchange at 162 MeV

    International Nuclear Information System (INIS)

    Nilsson, J.; Blomgren, J.; Conde, H.; Elmgren, K.; Olsson, N.; Ericson, T.E.O.; Uppsala Univ.; Jonsson, O.; Nilsson, L.; Loiseau, B.; Ringbom, A.

    1995-02-01

    Differential cross sections for unpolarized neutrons of 162 MeV have been measured to high precision with particular attention to the absolute normalisation. These data can be extrapolated precisely and model-independently to the pion pole and give a πNN coupling constant g 2 =14.6±0.3 or f 2 =0.0808±0.0017. This is higher than recently suggested values. (author) 24 refs.; 3 figs.; 1 tab

  11. Coupling vibration research on Vehicle-bridge system

    Science.gov (United States)

    Zhou, Jiguo; Wang, Guihua

    2018-01-01

    The vehicle-bridge coupling system forms when vehicle running on a bridge. It will generate a relatively large influence on the driving comfort and driving safe when the vibration of the vehicle is bigger. A three-dimensional vehicle-bridge system with biaxial seven degrees of freedom has been establish in this paper based on finite numerical simulation. Adopting the finite element transient numerical simulation to realize the numerical simulation of vehicle-bridge system coupling vibration. Then, analyze the dynamic response of vehicle and bridge while different numbers of vehicles running on the bridge. Got the variation rule of vertical vibration of car body and bridge, and that of the contact force between the wheel and bridge deck. The research results have a reference value for the analysis about the vehicle running on a large-span cabled bridge.

  12. High-power fiber-coupled 100W visible spectrum diode lasers for display applications

    Science.gov (United States)

    Unger, Andreas; Küster, Matthias; Köhler, Bernd; Biesenbach, Jens

    2013-02-01

    Diode lasers in the blue and red spectral range are the most promising light sources for upcoming high-brightness digital projectors in cinemas and large venue displays. They combine improved efficiency, longer lifetime and a greatly improved color space compared to traditional xenon light sources. In this paper we report on high-power visible diode laser sources to serve the demands of this emerging market. A unique electro-optical platform enables scalable fiber coupled sources at 638 nm with an output power of up to 100 W from a 400 μm NA0.22 fiber. For the blue diode laser we demonstrate scalable sources from 5 W to 100 W from a 400 μm NA0.22 fiber.

  13. Evaluation of coupled thermo-hydro-mechanical phenomena in the near field for geological disposal of high-level radioactive waste

    International Nuclear Information System (INIS)

    Chijimatsu, Masakazu; Fujita, Tomoo; Sugita, Yutaka; Taniguchi, Wataru

    2000-01-01

    Geological disposal of high-level radioactive waste (HLW) in Japan is based on a multibarrier system composed of engineered and natural barriers. The engineered barriers are composed of vitrified waste confined within a canister, overpack and buffer material. Highly compacted bentonite clay is considered one of the most promising candidate buffer material mainly because of its low hydraulic conductivity and high adsorption capacity of radionuclides. In a repository of HLW, complex thermal, hydraulic and mechanical (T-H-M) phenomena will take place, involving the interactive processes between radioactive decay heat from the vitrified waste, infiltration of ground water and stress generation due to the earth pressure, the thermal loading and the swelling pressure of the buffer material. In order to evaluate the performance of the buffer material, the coupled T-H-M behaviors within the compacted bentonite have to be modelled. Before establishing a fully coupled T-H-M model, the mechanism of each single phenomenon or partially coupled phenomena should be identified. Furthermore, in order to evaluate the coupled T-H-M phenomena, the analysis model was developed physically and numerically and the adequacy and the applicability was tested though the engineered scale laboratory test and in-situ test. In this report, the investigative results for the development of coupled T-H-M model were described. This report consists of eight chapters. In Chapter 1, the necessity of coupled T-H-M model in the geological disposal project of the high-level radioactive waste was described . In Chapter 2, the laboratory test results of the rock sample and the buffer material for the coupled T-H-M analysis were shown. The rock samples were obtained from the in-situ experimental site at Kamaishi mine. As the buffer material, bentonite clay (Kunigel V1 and Kunigel OT-9607) and bentonite-sand mixture were used. In Chapter 3, in-situ tests to obtain the rock property were shown. As in-situ tests

  14. Evaluation of coupled thermo-hydro-mechanical phenomena in the near field for geological disposal of high-level radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Chijimatsu, Masakazu; Fujita, Tomoo; Sugita, Yutaka; Taniguchi, Wataru [Japan Nuclear Cycle Development Inst., Tokai Works, Waste Management and Fuel Cycle Research Center, Waste Isolation Research Division, Barrier Performance Group, Tokai, Ibaraki (Japan)

    2000-01-01

    Geological disposal of high-level radioactive waste (HLW) in Japan is based on a multibarrier system composed of engineered and natural barriers. The engineered barriers are composed of vitrified waste confined within a canister, overpack and buffer material. Highly compacted bentonite clay is considered one of the most promising candidate buffer material mainly because of its low hydraulic conductivity and high adsorption capacity of radionuclides. In a repository of HLW, complex thermal, hydraulic and mechanical (T-H-M) phenomena will take place, involving the interactive processes between radioactive decay heat from the vitrified waste, infiltration of ground water and stress generation due to the earth pressure, the thermal loading and the swelling pressure of the buffer material. In order to evaluate the performance of the buffer material, the coupled T-H-M behaviors within the compacted bentonite have to be modelled. Before establishing a fully coupled T-H-M model, the mechanism of each single phenomenon or partially coupled phenomena should be identified. Furthermore, in order to evaluate the coupled T-H-M phenomena, the analysis model was developed physically and numerically and the adequacy and the applicability was tested though the engineered scale laboratory test and in-situ test. In this report, the investigative results for the development of coupled T-H-M model were described. This report consists of eight chapters. In Chapter 1, the necessity of coupled T-H-M model in the geological disposal project of the high-level radioactive waste was described . In Chapter 2, the laboratory test results of the rock sample and the buffer material for the coupled T-H-M analysis were shown. The rock samples were obtained from the in-situ experimental site at Kamaishi mine. As the buffer material, bentonite clay (Kunigel V1 and Kunigel OT-9607) and bentonite-sand mixture were used. In Chapter 3, in-situ tests to obtain the rock property were shown. As in-situ tests

  15. Determination of technetium-99 in soil samples by high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Muto, Toshio; Shimokawa, Toshinari

    1997-01-01

    A new powerful analytical technique viz. high performance liquid chromatography(HPLC) coupled to inductively coupled plasma mass spectrometry(HPLC/ICP-MS) has been applied to the determination of technetium-99( 99 Tc) in soils as a typical environmental sample. Technetium was enriched in a solution from incinerated soil samples by leaching in HNO 3 and passed through 'TEVA resin' column. The solution was injected into HPLC/ICP-MS system to eliminate the interfering elements (i.e. Ru and Mo) and to determine the 99 Tc concentration at the same time. The concentrations of 99 Tc in the incinerated soils were found to be 0.49Bq/kg(0.77ng/kg)-1.4Bq/kg(2.2ng/kg) with the determination limit of 0.02Bq/kg(0.03ng/kg(0.03ppt)). The results indicate the following findings; 1) the determination of 99 Tc by ICP-MS after strict elimination of the interfering elements by HPLC brings about the improvement in their reliability; 2) the detection limits identified are much lower compared with those by conventional ICP-MS methods because of the concentration of 99 Tc to smaller volume, which is due to only 100μl of samples could be measured by HPLC/ICP-MS system; 3) sample preparation could be simplified because of strict elimination of the interfering elements by HPLC. This research showed that HPLC/ICP-MS system is very effective to determine 99 Tc in environmental samples. (author)

  16. A comparison of high and low degree of freedom alignment techniques in functional PET brain activation experiments)

    International Nuclear Information System (INIS)

    Sonkkila, C.P.; Egan, G.F.; Watson, J.D.G.; Wenderoth, P.

    1998-01-01

    Full text: Cognitive activation studies in PET commonly utilise intersubject alignment as a preprocessing stage before images are compared. The accepted technique included in statistical parametric mapping (SPM) an analysis package developed by Friston et al, uses a 12 'degree of freedom' (d.o.f.) affine transformation, while a more complicated non-linear approach has recently been developed by Woods et al, but it necessitates the use of higher resolution magnetic resonance images to give sufficient information to use the high degree of freedom nonlinear alignment. This study seeks to show the differences between using the low degree of freedom alignment approach in SPM compared to that of Woods. As an example, a group of 8 normal subjects are asked to perform a complex visual paradigm during a series of PET scans designed to be sensitive to changes in blood flow. Structural MR images are also acquired for each subject. The resulting scans are then analysed with two methods: One where all images are aligned using SPM and the PET images. The second method utilises Woods' algorithm (a 5th order polynomial fit with 168 d.o.f.) and the MR images. SPM is then used to assess regions of significant change in blood flow across the group for both methods, and the results compared. When using the PET images for alignment purposes, the maximal probability for rejecting the null hypothesis of no change in regional blood flow was p = 0.471 (Talairach atlas coordinate 10 -74 -8) while utilising the MR images gives p = 0.913 for the same region. Note that to reach higher statistical significance ( eg p > 0.95 ) more subjects would be included in the study. It was concluded that there is considerable evidence to show that using MR images and Woods' nonlinear alignment gives higher statistical power than using PET images only and a low degree of freedom alignment method for resolving changes in regional blood flow in cognitive activation experiments

  17. Highly relativistic magnetospheric electrons: A role in coupling to the middle atmosphere?

    International Nuclear Information System (INIS)

    Baker, D.N.; Blake, J.B.; Gorney, D.J.; Higbie, P.R.; Klebesadel, R.W.; King, J.H.

    1987-01-01

    Long-term (1979-present) observations of relativistic electrons (2--15 MeV) at geostationary orbit show a strong solar cycle dependence. Such electrons were largely absent near the last solar maximum (1979--80), while they were prominent during the approach to solar minimum (1983--85). This population now is dwindling as solar minimum has been reached. The strong magnetospheric presence of high-speed solar wind streams which results from solar coronal hole structures during the approach to solar activity (sunspot) minimum. We clearly observe 27-day periodic enhancements of the relativistic electrons in association with concurrently measured solar wind streams (V/sub S//sub W/approx. >600 km/s). We have used a numerical transport code to study the coupling of these high-energy electrons to earth's upper and middle atmosphere. We calculate using the observed energy spectra of the electrons that, when precipitated, these electrons show a large (maximum of ∼100 keV/cm 3 -s) energy deposition at 40--60 km altitude, which is 3--4 orders of magnitude greater than the galactic cosmic ray or solar EUV energy deposition at these altitudes. We also find that the global energy deposition in the mid-latitudes totals nearly 10 21 ergs for a typical 2--3 day event period. We conclude that this previously unrecognized electron population could play an important role in coupling solar wind and magnetospheric variability (on 27--day and 11--year cycles) to the middle atmosphere through a modulating effect on lower D-region ionization and, possibly, on upper level ozone chemistry. These electrons also may contribute to the recent Antarctic polar ozone depletion phenomenon. copyright American Geophysical Union 1987

  18. Coupled thermo-hydro-mechanical analysis for the conceptual repository of high-level radioactive waste in China

    International Nuclear Information System (INIS)

    Lin, Y.M.; Wang, J.; Ke, D.; Cai, M.F.

    2010-01-01

    In order to safely dispose of the high-level radioactive waste (HLW), RD guide of HLW disposal was published in February 2006 in China. The spent fuel from nuclear power plants will be reprocessed first, followed by verification and final disposal. A conceptual repository 3D configuration comprises a single vertical borehole in a continuous and homogeneous hard rock, containing a canister surrounded by an over-pack and a bentonite layer, and the backfilled upper portion of the gallery using FLAC3D. To take into account in situ stress, geothermal gradient and groundwater of Beishan area, thermal relief of HLW and swelling pressure of buffer/backfill material made by GMZ01 bentonite, the TM, HM and THM evolution of the whole configuration is simulated over a period of 100 years. The results demonstrate that temperature is hardly affected by the couplings. In contrast, the influence of the couplings on the mechanical stresses is considerable. The repository has long-term stability in fully THM coupling action condition. (authors)

  19. Probing WWγ and WWγγ couplings with high energy photon beams

    International Nuclear Information System (INIS)

    Choi, S.Y.; Schrempp, F.

    1992-01-01

    The potential of a 500 GeV 'Next Linear e + e - Collider' (NLC) for probing anomalous WWγ and WWγγ couplings in the γ(γ) mode is investigated. The γe - →W - ν and the γγ→W + W - processes are studied. Differential cross sections are given for polarized and unpolarized beams. CP violating couplings are also discussed. (K.A.) 13 refs., 6 figs

  20. Control of coupled oscillator networks with application to microgrid technologies

    Science.gov (United States)

    Arenas, Alex

    The control of complex systems and network-coupled dynamical systems is a topic of vital theoretical importance in mathematics and physics with a wide range of applications in engineering and various other sciences. Motivated by recent research into smart grid technologies, we study the control of synchronization and consider the important case of networks of coupled phase oscillators with nonlinear interactions-a paradigmatic example that has guided our understanding of self-organization for decades. We develop a method for control based on identifying and stabilizing problematic oscillators, resulting in a stable spectrum of eigenvalues, and in turn a linearly stable syn- chronized state. The amount of control, that is, number of oscillators, required to stabilize the network is primarily dictated by the coupling strength, dynamical heterogeneity, and mean degree of the network, and depends little on the structural heterogeneity of the network itself.

  1. Control of coupled oscillator networks with application to microgrid technologies.

    Science.gov (United States)

    Skardal, Per Sebastian; Arenas, Alex

    2015-08-01

    The control of complex systems and network-coupled dynamical systems is a topic of vital theoretical importance in mathematics and physics with a wide range of applications in engineering and various other sciences. Motivated by recent research into smart grid technologies, we study the control of synchronization and consider the important case of networks of coupled phase oscillators with nonlinear interactions-a paradigmatic example that has guided our understanding of self-organization for decades. We develop a method for control based on identifying and stabilizing problematic oscillators, resulting in a stable spectrum of eigenvalues, and in turn a linearly stable synchronized state. The amount of control, that is, number of oscillators, required to stabilize the network is primarily dictated by the coupling strength, dynamical heterogeneity, and mean degree of the network, and depends little on the structural heterogeneity of the network itself.

  2. On equivalence of high temperature series expansion and coupling parameter series expansion in thermodynamic perturbation theory of fluids

    International Nuclear Information System (INIS)

    Sai Venkata Ramana, A.

    2014-01-01

    The coupling parameter series expansion and the high temperature series expansion in the thermodynamic perturbation theory of fluids are shown to be equivalent if the interaction potential is pairwise additive. As a consequence, for the class of fluids with the potential having a hardcore repulsion, if the hard-sphere fluid is chosen as reference system, the terms of coupling parameter series expansion for radial distribution function, direct correlation function, and Helmholtz free energy follow a scaling law with temperature. The scaling law is confirmed by application to square-well fluids

  3. Fully vs. Sequentially Coupled Loads Analysis of Offshore Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Damiani, Rick; Wendt, Fabian; Musial, Walter; Finucane, Z.; Hulliger, L.; Chilka, S.; Dolan, D.; Cushing, J.; O' Connell, D.; Falk, S.

    2017-06-19

    The design and analysis methods for offshore wind turbines must consider the aerodynamic and hydrodynamic loads and response of the entire system (turbine, tower, substructure, and foundation) coupled to the turbine control system dynamics. Whereas a fully coupled (turbine and support structure) modeling approach is more rigorous, intellectual property concerns can preclude this approach. In fact, turbine control system algorithms and turbine properties are strictly guarded and often not shared. In many cases, a partially coupled analysis using separate tools and an exchange of reduced sets of data via sequential coupling may be necessary. In the sequentially coupled approach, the turbine and substructure designers will independently determine and exchange an abridged model of their respective subsystems to be used in their partners' dynamic simulations. Although the ability to achieve design optimization is sacrificed to some degree with a sequentially coupled analysis method, the central question here is whether this approach can deliver the required safety and how the differences in the results from the fully coupled method could affect the design. This work summarizes the scope and preliminary results of a study conducted for the Bureau of Safety and Environmental Enforcement aimed at quantifying differences between these approaches through aero-hydro-servo-elastic simulations of two offshore wind turbines on a monopile and jacket substructure.

  4. Predictors of depressive symptoms in older rural couples: the impact of work, stress and health.

    Science.gov (United States)

    Rayens, Mary Kay; Reed, Deborah B

    2014-01-01

    Older farmers experience a high rate of suicide, and depression is closely aligned with suicide among agricultural workers. Depressive symptoms may be influenced by work patterns, work satisfaction, stress, and health status. In addition, members of a couple may affect each other's depressive symptoms. The purpose was to determine whether depressive symptoms score is predicted by hours worked on the farm, satisfaction with work, number of health conditions, perceived stress, and demographics in a sample of older farm couples, and to assess the degree of influence on depressive symptoms spouses have on each other. A total of 494 couples participated in the initial interview for a longitudinal study of farmers aged 50 and above. Data from husbands and wives were used together in a multilevel, dyad-based regression model to determine predictors of depressive symptoms. Men's depressive symptoms scores were predicted by their own number of health conditions and stress and by their wives' stress and health conditions. Women's depressive symptoms scores were predicted by their own work satisfaction, stress, and number of health conditions and their husbands' time spent working on the farm and stress. Stress management may be particularly important in older farm couples, since perceived duress of 1 member of the dyad impacts both. Work factors and health conditions also affect depressive symptoms in older rural couples, but these may be less easily modified. © 2013 National Rural Health Association.

  5. Spatiotemporal complexity in coupled map lattices

    International Nuclear Information System (INIS)

    Kaneko, Kunihiko

    1986-01-01

    Some spatiotemporal patterns of couple map lattices are presented. The chaotic kink-like motions are shown for the phase motion of the coupled circle lattices. An extension of the couple map lattice approach to Hamiltonian dynamics is briefly reported. An attempt to characterize the high-dimensional attractor by the extension of the correlation dimension is discussed. (author)

  6. The use of coupled atmospheric and hydrological models for water-resources management in headwater basins

    Science.gov (United States)

    Leavesley, G.; Hay, L.

    1998-01-01

    Coupled atmospheric and hydrological models provide an opportunity for the improved management of water resources in headwater basins. Issues currently limiting full implementation of coupled-model methodologies include (a) the degree of uncertainty in the accuracy of precipitation and other meteorological variables simulated by atmospheric models, and (b) the problem of discordant scales between atmospheric and bydrological models. Alternative methodologies being developed to address these issues are reviewed.

  7. High resolution spectroscopy of 1,2-difluoroethane in a molecular beam: A case study of vibrational mode-coupling

    Science.gov (United States)

    Mork, Steven W.; Miller, C. Cameron; Philips, Laura A.

    1992-09-01

    The high resolution infrared spectrum of 1,2-difluoroethane (DFE) in a molecular beam has been obtained over the 2978-2996 cm-1 spectral region. This region corresponds to the symmetric combination of asymmetric C-H stretches in DFE. Observed rotational fine structure indicates that this C-H stretch is undergoing vibrational mode coupling to a single dark mode. The dark mode is split by approximately 19 cm-1 due to tunneling between the two identical gauche conformers. The mechanism of the coupling is largely anharmonic with a minor component of B/C plane Coriolis coupling. Effects of centrifugal distortion along the molecular A-axis are also observed. Analysis of the fine structure identifies the dark state as being composed of C-C torsion, CCF bend, and CH2 rock. Coupling between the C-H stretches and the C-C torsion is of particular interest because DFE has been observed to undergo vibrationally induced isomerization from the gauche to trans conformer upon excitation of the C-H stretch.

  8. Dynamics of coupled electron-nuclei-systems in laser fields; Dynamik gekoppelter Elektronen-Kern-Systeme in Laserfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Falge, Mirjam

    2012-07-01

    This work aimed at the theoretical analysis of high harmonic generation in molecules and the influence of coupled electron and nuclear dynamics on ultra-short pulse ionization processes. In the first part of this thesis, the isotope effect and influence of vibrational excitation on high harmonic generation were investigated for the isotope pairs H{sub 2}O/D{sub 2}O and H{sub 2}/D{sub 2}. It was shown that on the one hand high harmonic intensities strongly depend on the vibrational quantum number of the initial state of the water molecule and on the other hand the spectra of H{sub 2}O and D{sub 2}O exhibit a clear isotope effect for certain vibrationally excited states. Also it was shown that high harmonics of vibrationally excited states show an even more pronounced isotope effect than the ground state. The second and third part of this work treats the influence of coupled electron and nuclear dynamics on photoelectron spectra. In order to facilitate a numerically exact description of this dynamics, a simple one-dimensional model system (Shin-Metiu model) was used. It consists of only a single electronic and nuclear degree-of-freedom and allows for a switching between adiabatic and strongly non-adiabatic dynamics by its parameterization. This model served for the analysis of the dynamics of three different cases ranging from weak over intermediate to strong electron-nuclear coupling. To investigate the influence of non-adiabatic effects on photoelectron spectra, time-resolved photoelectron spectra were calculated applying two methods: a numerically exact treatment and an adiabatic approach neglecting the electron-nuclear coupling. Subsequently, the dependence of the efficiency of a non-adiabatic transition on the nuclear mass was analysed. To this end, the population dynamics and photoelectron spectra were calculated numerically exactly for a strong electron and nuclear coupling. Thereafter the asymmetry in forward and backward direction of time

  9. Baryon bags in strong coupling QCD

    Science.gov (United States)

    Gattringer, Christof

    2018-04-01

    We discuss lattice QCD with one flavor of staggered fermions and show that in the path integral the baryon contributions can be fully separated from quark and diquark contributions. The baryonic degrees of freedom (d.o.f.) are independent of the gauge field, and the corresponding free fermion action describes the baryons through the joint propagation of three quarks. The nonbaryonic dynamics is described by quark and diquark terms that couple to the gauge field. When evaluating the quark and diquark contributions in the strong coupling limit, the partition function completely factorizes into baryon bags and a complementary domain. Baryon bags are regions in space-time where the dynamics is described by a single free fermion made out of three quarks propagating coherently as a baryon. Outside the baryon bags, the relevant d.o.f. are monomers and dimers for quarks and diquarks. The partition sum is a sum over all baryon bag configurations, and for each bag, a free fermion determinant appears as a weight factor.

  10. High efficiency all-optical plasmonic diode based on a nonlinear side-coupled waveguide-cavity structure with broken symmetry

    Science.gov (United States)

    Liang, Hong-Qin; Liu, Bin; Hu, Jin-Feng; He, Xing-Dao

    2018-05-01

    An all-optical plasmonic diode, comprising a metal-insulator-metal waveguide coupled with a stub cavity, is proposed based on a nonlinear Fano structure. The key technique used is to break structural spatial symmetry by a simple reflector layer in the waveguide. The spatial asymmetry of the structure gives rise to the nonreciprocity of coupling efficiencies between the Fano cavity and waveguides on both sides of the reflector layer, leading to a nonreciprocal nonlinear response. Transmission properties and dynamic responses are numerically simulated and investigated by the nonlinear finite-difference time-domain method. In the proposed structure, high-efficiency nonreciprocal transmission can be achieved with a low power threshold and an ultrafast response time (subpicosecond level). A high maximum transmittance of 89.3% and an ultra-high transmission contrast ratio of 99.6% can also be obtained. The device can be flexibly adjusted for working wavebands by altering the stub cavity length.

  11. Dibaryonic degrees of freedom in Hadronic and nuclear physics

    International Nuclear Information System (INIS)

    Kukulin, V.I.; Shikhalev, M.A.

    2005-01-01

    The basic aim of the talk is to show that the dibaryons (independently upon the fact of existence or nonexistence of narrow dibaryons) may become one of the main ingredients and degrees of freedom in hadronic and nuclear physics. It follows straightforwardly from the new model for nuclear force, in which the intermediate-state dibaryons play the role of main carriers of strong interaction of nucleons at intermediate and short ranges in 2N, 3N and other nuclear systems. These intermediate-state dibaryons, or dressed six-quark bags in NN-scattering are strongly coupled to the initial and final NN-channels and thus they have large widths which prevent their direct experimental evidence. However the new model predicts a lot of new effects of dibaryons, which should be seen experimentally in hadronic and nuclear processes. Some of these new predictions have been already confirmed in numerous calculations made jointly in Moscow and Tuebingen university groups. We enumerate shortly here only the most interesting effects of dibaryons in hadronic and nuclear physics: (i) partial restoration of chiral symmetry in multiquark (i.e. 6q, 9q etc.) systems with the respective reduction of the scalar sigma-meson mass; (ii) enhancement of the near-threshold π 0 and π + π − , π 0 π 0 – production in pp, pd etc. collisions; explanation of the long-term ABC-puzzle; (iii) enhancement of the vector-meson and (e + e − ) production in the GeV region in pp, pd etc. collisions; (iv) large yield of cumulative mesons and other hadrons (studied experimentally by Baldin with coworkers) in p-A, d-A etc. high-energy collisions; (v) new electro-magnetic currents related intimately to the dibaryon degrees of freedom, which contribute to the all deuteron e.-m. observables, like deuteron magnetic and quadrupole moments, cross sections of photo-disintegration etc.; (vi) some novel contribution to the Coulomb energies of all nuclei (∼ 15%), which is able to explain the long-standing Nollen

  12. Belpex and trilateral market coupling

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-01-15

    This document describes the operation of Belpex, the Belgian power transmission spot market, and its linking with the French (Powernext) and Dutch (APX) auction-style day-ahead spot markets. A last part deals with the extension of this trilateral market to other European countries. Content: Belpex day-ahead market (DAM) (Goals of the DAM: Provide consumers with a wider choice of electrical energy sources, Enable the ARP's to optimize their portfolio in terms of imbalance costs, Reduce trade and credit risks for market players compared with the risks involved in concluding bilateral contracts, Provide economic players with a transparent price benchmark, Stimulate the opening of the electricity market); Market model Product (description, Contracts, Collateral calculation, From 12 January to launch date Corporate and Legal Aspects, Next developments); Trilateral Market Coupling (What is market coupling and what are the benefits?, Implementation of trilateral market coupling ('TLC') in France/Belgium/Netherlands, From Trilateral to Multilateral, Implementation of Trilateral Market Coupling (TLC) in France/Belgium/Netherlands, Decentralized market coupling mechanism, influence of import and export on area prices); Decentralized market coupling (2 countries Situations: unconstrained/constrained, Decentralized market coupling: 3 countries, High Level Properties of Market Coupling, Maximize flow until prices across link converge (or ATC limit reached), Power flows from low price area to high price area, Implementing a decentralized technical approach, Market Coupling Daily Process, Impact on Existing Exchange Arrangements, Implementing a decentralized contractual approach, TLC Project Process); From Trilateral to Multilateral (Geographic extensions, Towards an Open and Multilateral Market Coupling, Management of Interconnection Capacities, Interconnection Capacities: current situation, TSO Roles and Responsibilities in the TLC, Other Import/Export products

  13. Belpex and trilateral market coupling

    International Nuclear Information System (INIS)

    2006-01-01

    This document describes the operation of Belpex, the Belgian power transmission spot market, and its linking with the French (Powernext) and Dutch (APX) auction-style day-ahead spot markets. A last part deals with the extension of this trilateral market to other European countries. Content: Belpex day-ahead market (DAM) (Goals of the DAM: Provide consumers with a wider choice of electrical energy sources, Enable the ARP's to optimize their portfolio in terms of imbalance costs, Reduce trade and credit risks for market players compared with the risks involved in concluding bilateral contracts, Provide economic players with a transparent price benchmark, Stimulate the opening of the electricity market); Market model Product (description, Contracts, Collateral calculation, From 12 January to launch date Corporate and Legal Aspects, Next developments); Trilateral Market Coupling (What is market coupling and what are the benefits?, Implementation of trilateral market coupling ('TLC') in France/Belgium/Netherlands, From Trilateral to Multilateral, Implementation of Trilateral Market Coupling (TLC) in France/Belgium/Netherlands, Decentralized market coupling mechanism, influence of import and export on area prices); Decentralized market coupling (2 countries Situations: unconstrained/constrained, Decentralized market coupling: 3 countries, High Level Properties of Market Coupling, Maximize flow until prices across link converge (or ATC limit reached), Power flows from low price area to high price area, Implementing a decentralized technical approach, Market Coupling Daily Process, Impact on Existing Exchange Arrangements, Implementing a decentralized contractual approach, TLC Project Process); From Trilateral to Multilateral (Geographic extensions, Towards an Open and Multilateral Market Coupling, Management of Interconnection Capacities, Interconnection Capacities: current situation, TSO Roles and Responsibilities in the TLC, Other Import/Export products on the

  14. Effects of extracellular potassium diffusion on electrically coupled neuron networks

    Science.gov (United States)

    Wu, Xing-Xing; Shuai, Jianwei

    2015-02-01

    Potassium accumulation and diffusion during neuronal epileptiform activity have been observed experimentally, and potassium lateral diffusion has been suggested to play an important role in nonsynaptic neuron networks. We adopt a hippocampal CA1 pyramidal neuron network in a zero-calcium condition to better understand the influence of extracellular potassium dynamics on the stimulus-induced activity. The potassium concentration in the interstitial space for each neuron is regulated by potassium currents, Na+-K+ pumps, glial buffering, and ion diffusion. In addition to potassium diffusion, nearby neurons are also coupled through gap junctions. Our results reveal that the latency of the first spike responding to stimulus monotonically decreases with increasing gap-junction conductance but is insensitive to potassium diffusive coupling. The duration of network oscillations shows a bell-like shape with increasing potassium diffusive coupling at weak gap-junction coupling. For modest electrical coupling, there is an optimal K+ diffusion strength, at which the flow of potassium ions among the network neurons appropriately modulates interstitial potassium concentrations in a degree that provides the most favorable environment for the generation and continuance of the action potential waves in the network.

  15. Population equations for degree-heterogenous neural networks

    Science.gov (United States)

    Kähne, M.; Sokolov, I. M.; Rüdiger, S.

    2017-11-01

    We develop a statistical framework for studying recurrent networks with broad distributions of the number of synaptic links per neuron. We treat each group of neurons with equal input degree as one population and derive a system of equations determining the population-averaged firing rates. The derivation rests on an assumption of a large number of neurons and, additionally, an assumption of a large number of synapses per neuron. For the case of binary neurons, analytical solutions can be constructed, which correspond to steps in the activity versus degree space. We apply this theory to networks with degree-correlated topology and show that complex, multi-stable regimes can result for increasing correlations. Our work is motivated by the recent finding of subnetworks of highly active neurons and the fact that these neurons tend to be connected to each other with higher probability.

  16. Contraception knowledge status of marriage applicants couples in the Van city

    Directory of Open Access Journals (Sweden)

    Ahmet Yılmaz

    2013-09-01

    Full Text Available This study was performed to determine ofcontraception knowledge levels and planning contraceptionmethods after marriage that couples have applied tofamily planning center in the Van city.Methods: Study has planned as descriptive manner. Thisstudy was performed on 255 couples who have appliedfor official wedding procedure to Van maternal and childhealth and family planning center between September2010 - January 2011. Participants were determined on avoluntary basis. Questionnaires were filled out by familymedicine face to face with couples.Results: Totally, 21.3% percent of women, 23.5% percentof men have primary school degree. 18% of women,93.4% of men have a profession. 12.1% percent of womenand 12.9% percent of men does not have any knowledgeabout contraceptive and 43% of couples do not consideruse any contraceptive method after marriage. The resultshas shown that when evaluate the couples, in terms ofthe distribution of contraception information, the coupleshave more information about condoms, pills, coil, injectionand withdraw methods then tube ligation, implants,spermicides, vasectomy and the calendar methodsConclusion: Van region has a low socio-economic status.The couples should be informed about family planningbefore marriage, to talk about advantages of collaborationbetween the couples about birth control methodchoice.Key words: Reproductive health, family planning, contraception

  17. Descriptions of the equilibration process of the intrinsic degrees of freedom and dissipative process of the nuclear collective motion

    International Nuclear Information System (INIS)

    Feng Renfa; Zhang Jingshang; Ma Zhongyu; Wu Xizhen; Zhuo Yizhong

    1984-01-01

    In this paper the Hamiltonian model is used for studying the nuclear dynamics by taking both the one-body and two-body interaction mechanisms into account. On the basis of the Von Neuman equation the coupling between the collective motion and the single particle degrees of freedom is discussed. Thus, the equations obtained are physically transparent and easy for numerical computations. They may be useful for describing the dissipative process of the nuclear collective motion as well as the equilibration process of the intrinsic degrees of freedom. (Author)

  18. G protein-coupled receptor internalization assays in the high-content screening format.

    Science.gov (United States)

    Haasen, Dorothea; Schnapp, Andreas; Valler, Martin J; Heilker, Ralf

    2006-01-01

    High-content screening (HCS), a combination of fluorescence microscopic imaging and automated image analysis, has become a frequently applied tool to study test compound effects in cellular disease-modeling systems. This chapter describes the measurement of G protein-coupled receptor (GPCR) internalization in the HCS format using a high-throughput, confocal cellular imaging device. GPCRs are the most successful group of therapeutic targets on the pharmaceutical market. Accordingly, the search for compounds that interfere with GPCR function in a specific and selective way is a major focus of the pharmaceutical industry today. This chapter describes methods for the ligand-induced internalization of GPCRs labeled previously with either a fluorophore-conjugated ligand or an antibody directed against an N-terminal tag of the GPCR. Both labeling techniques produce robust assay formats. Complementary to other functional GPCR drug discovery assays, internalization assays enable a pharmacological analysis of test compounds. We conclude that GPCR internalization assays represent a valuable medium/high-throughput screening format to determine the cellular activity of GPCR ligands.

  19. Effects of high-frequency yoga breathing called kapalabhati compared with breath awareness on the degree of optical illusion perceived.

    Science.gov (United States)

    Telles, Shirley; Maharana, Kanchan; Balrana, Budhi; Balkrishna, Acharya

    2011-06-01

    Prior research has shown that methods of meditation, breath control, and different kinds of yoga breathing affect attention and visual perception, including decreasing the size of certain optical illusions. Evaluating relationships sheds light on the perceptual and cognitive changes induced by yoga and related methods, and the locus of the effects. In the present study, the degree of optical illusion was assessed using Müller-Lyer stimuli before and immediately after two different kinds of practice, a high frequency yoga breathing called kapalabhati, and breath awareness. A nonyoga, control session tested for practice effects. Thirty participants (with group M age = 26.9 yr., SD = 5.7) practiced the two techniques for 18 min. on two separate days. The control group had 15 nonyoga practitioners assessed before and after 18 min. in which they did not perform any specific activity but were seated and relaxed. After both kapalabhati and breath awareness there was a significant decrease in the degree of optical illusion. The possibility that this was due to a practice or repetition effect was ruled out when 15 nonyoga practitioners showed no change in the degree of illusion when retested after 18 min. The changes were interpreted as due to changes in perception related to the way the stimuli were judged.

  20. The impact of high-risk drivers and benefits of limiting their driving degree of freedom.

    Science.gov (United States)

    Habtemichael, Filmon G; de Picado-Santos, Luis

    2013-11-01

    The perception of drivers regarding risk-taking behaviour is widely varied. High-risk drivers are the segment of drivers who are disproportionately represented in the majority of crashes. This study examines the typologies of drivers in risk-taking behaviour, the common high-risk driving errors (speeding, close following, abrupt lane-changing and impaired driving), their safety consequences and the technological (ITS) devices for their detection and correction. Limiting the driving degree of freedom of high-risk drivers is proposed and its benefits on safety as well as traffic operations are quantified using VISSIM microscopic traffic simulation at various proportions of high-risk drivers; namely, 4%, 8% and 12%. Assessment of the safety benefits was carried out by using the technique of simulated vehicle conflicts which was validated against historic crashes, and reduction in travel time was used to quantify the operational benefits. The findings imply that limiting the freedom of high-risk drivers resulted in a reduction of crashes by 12%, 21% and 27% in congested traffic conditions; 9%, 13% and 18% in lightly congested traffic conditions as well as 9%, 10% and 17% in non-congested traffic conditions for high-risk drivers in proportions of 4%, 8% and 12% respectively. Moreover, the surrogate safety measures indicated that there was a reduction in crash severity levels. The operational benefits amounted to savings of nearly 1% in travel time for all the proportions of high-risk drivers considered. The study concluded that limiting the freedom of high-risk drivers has safety and operational benefits; though there could be social, legal and institutional concerns for its practical implementation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Further studies on beam breakup growth reduction by cavity cross-couplings in recirculating accelerators: Effects of long pulse length and multiturn recirculation

    International Nuclear Information System (INIS)

    Colombant, D.; Lau, Y.Y.

    1992-01-01

    Cavity cross-coupling was recently found to reduce beam breakup (BBU) growth in a recirculating accelerator known as the Spiral Line Induction Accelerator (SLIA). Here, we extend the analysis in two prespects: ong beam pulse lengths and a SLIA upgrade geometry which accelerates a 10 kA, 35 ns beam to 25 MeV via a 70 cavity, 7 turn recirculation. We found that when the beam pulse length τ exceeds the beam's transit time τ' between cross-coupled cavities, BBU growth may be worsened as a result of the cross-coupling among cavities. This situation is not unlike other long pulse recirculating accelerators where beam recirculation leads to beam breakup of a regenerative type. Thus, the advantage of BBU reduction by cavity cross-coupling is restricted primarily to beams with τ<τ', a condition envisioned for all SLIA geometries. For the 70 gap, 7 turn SLIA upgrade, we found that cavity cross-coupling may reduce BBU growth up to factors of a thousand when the quality factor Q of the deflecting modes are relatively high (like 100). In these high Q cases, the amount of growth reduction depends on the arrangement and sequence of beam recirculation. For Q < or approx. 20, BBU growth reduction by factors of hundreds is observed, but this reduction is insensitive to the sequence of beam recirculation. The above conclusions were based on simple models of cavity coupling that have been used in conventional microwave literature. Not addressed is the detail design consideration that leads to the desired degree of cavity coupling. (orig.)

  2. The Effect of Mutual Coupling on a High Altitude Platform Diversity System Using Compact Antenna Arrays

    Directory of Open Access Journals (Sweden)

    Tommy Hult

    2010-01-01

    Full Text Available We analyze the destructive effects of mutual coupling and spatial correlation between the separate antenna elements on a combined diversity system consisting of multiple HAPs (High-Altitude Platforms employing various compact MIMO (Multiple-Input Multiple-Output antenna array configurations, in order to enhance the mutual information in HAP communication links. In addition, we assess the influence of the separation angle between HAPs on system performance, and determine the optimal separation angles that maximize the total mutual information of the system for various compact MIMO antennas. Simulation results show that although the mutual information is degraded by mutual coupling and spatial correlation, the proposed HAP diversity system still provides better performance compared to a nondiversity system for all tested scenarios.

  3. Oil spill model coupled to an ultra-high-resolution circulation model: implementation for the Adriatic Sea

    Science.gov (United States)

    Korotenko, K.

    2003-04-01

    An ultra-high-resolution version of DieCAST was adjusted for the Adriatic Sea and coupled with an oil spill model. Hydrodynamic module was developed on base of th low dissipative, four-order-accuracy version DieCAST with the resolution of ~2km. The oil spill model was developed on base of particle tracking technique The effect of evaporation is modeled with an original method developed on the base of the pseudo-component approach. A special dialog interface of this hybrid system allowing direct coupling to meteorlogical data collection systems or/and meteorological models. Experiments with hypothetic oil spill are analyzed for the Northern Adriatic Sea. Results (animations) of mesoscale circulation and oil slick modeling are presented at wabsite http://thayer.dartmouth.edu/~cushman/adriatic/movies/

  4. ESPC Coupled Global Prediction System

    Science.gov (United States)

    2015-09-30

    through an improvement to the sea ice albedo . Fig. 3: 2-m Temperature bias (deg C) of 120-h forecasts for the month of May 2014 for the Arctic...forecast system (NAVGEM) and ocean- sea ice forecast system (HYCOM/CICE) have never been coupled at high resolution. The coupled processes will be...winds and currents across the interface. The sea - ice component of this project requires modification of CICE versions 4 and 5 to run in the coupled

  5. Autonomy and couples' joint decision-making in healthcare.

    Science.gov (United States)

    Osamor, Pauline E; Grady, Christine

    2018-01-11

    Respect for autonomy is a key principle in bioethics. However, respecting autonomy in practice is complex because most people define themselves and make decisions influenced by a complex network of social relationships. The extent to which individual autonomy operates for each partner within the context of decision-making within marital or similar relationships is largely unexplored. This paper explores issues related to decision-making by couples (couples' joint decision-making) for health care and the circumstances under which such a practice should be respected as compatible with autonomous decision-making. We discuss the concept of autonomy as it applies to persons and to actions, human interdependency and gender roles in decision-making, the dynamics and outcomes of couples' joint decision-making, and the ethics of couples' joint decision-making. We believe that the extent to which couples' joint decision-making might be deemed ethically acceptable will vary depending on the context. Given that in many traditional marriages the woman is the less dominant partner, we consider a spectrum of scenarios of couples' joint decision-making about a woman's own health care that move from those that are acceptably autonomous to those that are not consistent with respecting the woman's autonomous decision-making. To the extent that there is evidence that both members of a couple understand a decision, intend it, and that neither completely controls the other, couples' joint decision-making should be viewed as consistent with the principle of respect for the woman's autonomy. At the other end of the spectrum are decisions made by the man without the woman's input, representing domination of one partner by the other. We recommend viewing the dynamics of couples' joint decision-making as existing on a continuum of degrees of autonomy. This continuum-based perspective implies that couples' joint decision-making should not be taken at face value but should be assessed against

  6. Patterns of strong coupling for LHC searches

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Da [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics,Chinese Academy of Sciences, Beijing, People’s Republic of (China); Theoretical Particle Physics Laboratory, Institute of Physics,EPFL, CH-1015 Lausanne (Switzerland); Pomarol, Alex [CERN, Theoretical Physics Department,1211 Geneva 23 (Switzerland); Dept. de Física and IFAE-BIST,Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona (Spain); Rattazzi, Riccardo [Theoretical Particle Physics Laboratory, Institute of Physics,EPFL, CH-1015 Lausanne (Switzerland); Riva, Francesco [CERN, Theoretical Physics Department,1211 Geneva 23 (Switzerland)

    2016-11-23

    Even though the Standard Model (SM) is weakly coupled at the Fermi scale, a new strong dynamics involving its degrees of freedom may conceivably lurk at slightly higher energies, in the multi TeV range. Approximate symmetries provide a structurally robust context where, within the low energy description, the dimensionless SM couplings are weak, while the new strong dynamics manifests itself exclusively through higher-derivative interactions. We present an exhaustive classification of such scenarios in the form of effective field theories, paying special attention to new classes of models where the strong dynamics involves, along with the Higgs boson, the SM gauge bosons and/or the fermions. The IR softness of the new dynamics suppresses its effects at LEP energies, but deviations are in principle detectable at the LHC, even at energies below the threshold for production of new states. We believe our construction provides the so far unique structurally robust context where to motivate several LHC searches in Higgs physics, diboson production, or WW scattering. Perhaps surprisingly, the interplay between weak coupling, strong coupling and derivatives, which is controlled by symmetries, can override the naive expansion in operator dimension, providing instances where dimension-8 dominates dimension-6, well within the domain of validity of the low energy effective theory. This result reveals the limitations of an analysis that is both ambitiously general and restricted to dimension-6 operators.

  7. Long-term stability of the near-field about high-level radioactive waste repository in thermo-hydro-mechanical coupling action condition

    International Nuclear Information System (INIS)

    Liu Yuemiao; Wang Ju; Ke Dan; Cai Meifeng

    2008-01-01

    It is a long-term process for the high-level radioactive waste repository, from opening, construction to end of its service. The long-term stability of the near-field is the key issue for the design of HLW repository because the opening and heat generated from the HLW. Through a nationwide investigation, Beishan area, a Gobi desert in Gansu province, is considered as a suitable candidate and GMZ bentonite deposit which located in Xinghe County, Inner Mongolia has been proposed for the supplier of buffer/backfill material for HLW geological repository in China. According to the R and D guide of high-level radioactive waste disposal in China, the 3D model of HLW repository with high-level radioactive waste, canister and buffer/backfill material is established using FLAC3D. To take into account in situ stress, geothermal gradient, groundwater, thermal relief of HLW and swelling pressure of buffer/backfill material, the evolution of temperature, stress and displacement of HLW repository under thermo-mechanical coupling, hydro-mechanical coupling and thermo-hydro-mechanical coupling conditions was analyzed respectively. The long-term stability of HLW repository in Beishan area was studied. (authors)

  8. Choroidal thickness in eyes with different degrees of myopia

    Directory of Open Access Journals (Sweden)

    Yuriy Sergeyevich Astakhov

    2013-12-01

    Full Text Available 66 healthy people (124 eyes with different degrees of myopia and emmetropia were examined using enhanced depth imaging optical coherence tomography (EDI-OCT using the “Spectralis OCT”. It was found that the choroid in subjects with medium and high degrees of myopia was significantly thinner than that in the control group. In the study, a negative correlation was found between the subfoveal choroidal thickness and the degree of myopia (r = -0.75, p < 0.0001. It was also found that the subfoveal choroidal thickness decreased for each diopter of myopia by approximately 18.03 μm.

  9. Resonant x-ray scattering in manganites: study of the orbital degree of freedom

    International Nuclear Information System (INIS)

    Ishihara, Sumio; Maekawa, Sadamichi

    2002-01-01

    The orbital degree of freedom of electrons and its interplay with spin, charge and lattice degrees of freedom are some of the central issues in colossal magnetoresistive manganites. The orbital degree of freedom has until recently remained hidden, since it does not couple directly to most experimental probes. Development of synchrotron light sources has changed the situation; by the resonant x-ray scattering (RXS) technique the orbital ordering has successfully been observed. In this article, we review progress in the recent studies of RXS in manganites. We start with a detailed review of the RXS experiments applied to the orbital-ordered manganites and other correlated electron systems. We derive the scattering cross section of RXS, where the tensor character of the atomic scattering factor (ASF) with respect to the x-ray polarization is stressed. Microscopic mechanisms of the anisotropic tensor character of the ASF are introduced and numerical results of the ASF and the scattering intensity are presented. The azimuthal angle scan is a unique experimental method to identify RXS from the orbital degree of freedom. A theory of the azimuthal angle and polarization dependence of the RXS intensity is presented. The theoretical results show good agreement with the experiments in manganites. Apart from the microscopic description of the ASF, a theoretical framework of RXS to relate directly to the 3d orbital is presented. The scattering cross section is represented by the correlation function of the pseudo-spin operator for the orbital degree of freedom. A theory is extended to the resonant inelastic x-ray scattering and methods to observe excitations of the orbital degree of freedom are proposed. (author)

  10. Dynamics of unidirectionally coupled bistable Henon maps

    International Nuclear Information System (INIS)

    Sausedo-Solorio, J.M.; Pisarchik, A.N.

    2011-01-01

    We study dynamics of two bistable Henon maps coupled in a master-slave configuration. In the case of coexistence of two periodic orbits, the slave map evolves into the master map state after transients, which duration determines synchronization time and obeys a -1/2 power law with respect to the coupling strength. This scaling law is almost independent of the map parameter. In the case of coexistence of chaotic and periodic attractors, very complex dynamics is observed, including the emergence of new attractors as the coupling strength is increased. The attractor of the master map always exists in the slave map independently of the coupling strength. For a high coupling strength, complete synchronization can be achieved only for the attractor similar to that of the master map. -- Highlights: → We study dynamics of two bistable Henon maps coupled in a master-slave configuration. → Synchronization time for periodic orbits obeys a -1/2 power law with respect to coupling. → For a high coupling strength, the slave map remains bistable. → Complete synchronization can be achieved only when both maps stay at the same attractor.

  11. Exploring Partner Intimacy Among Couples Raising Children on the Autism Spectrum: A Grounded Theory Investigation.

    Science.gov (United States)

    Johnson, Jake; Piercy, Fred P

    2017-10-01

    In this study, we explored how couples raising children with autism spectrum disorder negotiate intimacy, including what contextual and temporal factors influence these processes. We conducted conjoint interviews with 12 couples, employing grounded theory methodology to collect and analyze the data. Our results indicated that fostering intimacy in these couples' relationships involves partners working together to make key cognitive and relational shifts. Couples are aided or hindered in making these shifts by the degree to which they experience various contextual and environmental factors as resources or roadblocks. We also found that intimacy is not a fixed point at which couples one day arrive, but is an iterative process taking place over time and requiring work to develop and maintain. © 2017 American Association for Marriage and Family Therapy.

  12. Proximity of couples to parents: influences of gender, labor market, and family.

    Science.gov (United States)

    Chan, Tak Wing; Ermisch, John

    2015-04-01

    We use household survey data from the UK to study how close middle-aged men and women in partnerships live to their parents and their partner's parents. We find a slight tendency for couples to live closer to the woman's parents than the man's. This tendency is more pronounced among couples in which neither partner has a college degree and in which there is a child. In other respects, proximity to parents is gender-neutral, with the two partners having equal influence on intergenerational proximity. Better-educated couples live farther from their parents. And although certain family characteristics matter, intergenerational proximity is primarily driven by factors affecting mobility over long distances, which are mainly associated with the labor market, as opposed to gender or family circumstances.

  13. Tooth enamel oxygen "isoscapes" show a high degree of human mobility in prehistoric Britain.

    Science.gov (United States)

    Pellegrini, Maura; Pouncett, John; Jay, Mandy; Pearson, Mike Parker; Richards, Michael P

    2016-10-07

    A geostatistical model to predict human skeletal oxygen isotope values (δ 18 O p ) in Britain is presented here based on a new dataset of Chalcolithic and Early Bronze Age human teeth. The spatial statistics which underpin this model allow the identification of individuals interpreted as 'non-local' to the areas where they were buried (spatial outliers). A marked variation in δ 18 O p is observed in several areas, including the Stonehenge region, the Peak District, and the Yorkshire Wolds, suggesting a high degree of human mobility. These areas, rich in funerary and ceremonial monuments, may have formed focal points for people, some of whom would have travelled long distances, ultimately being buried there. The dataset and model represent a baseline for future archaeological studies, avoiding the complex conversions from skeletal to water δ 18 O values-a process known to be problematic.

  14. Structural stability of the smectite-doped lanthanum under high pressures and high temperatures

    International Nuclear Information System (INIS)

    Stefani, Vicente Fiorini

    2012-01-01

    Smectites are phyllosilicates that have a tetrahedron: octahedron structure ratio of 2:1, with high cation exchange capacity (CEC) in the interlayers. For these and other features, smectites have been used in many parts of the world as secondary barriers with the goal of containing a possible leak of radioactive elements in final disposal facilities for radioactive waste through cation exchange. Our aim in this work is to reach the cation exchange in calcium montmorillonite (smectite dioctahedral) by lanthanum to simulate trivalent radionuclides and to study the stability of this structure under high pressure and high temperature. To achieve high pressure it was used two different technique: DAC (Diamond Anvil Cell), achieving pressures up to 12GPa at room temperature and hydraulic press with a toroidal chamber profile to achieve pressures up to 7,7GPa and temperatures up to 900 degree C. The heating is achieved simultaneously by an electric system coupled in the hydraulic press. The outcomes show that the smectite structure doped with lanthanum remains stable under 12GPa at room temperature and 2.5GPa at 200 degree C. However, above 300 degree C at 2.5GPa the structure becomes a new phase of muscovite-like, rich of La, where it loses its interlayer water and turns out to be irreversible. Furthermore, it is important to point out that the higher temperature the better ordered is the structure and it is still stable under 7.7GPa and 900 degree C. Moreover, after all experiments the structure continues being dioctahedral. The new phase of muscovite-like, rich of La, in contact with a calcium solution remains partially unchanged, whereas the other part returns to the original structure (montmorillonite-Ca). The following analyses were performed: X-ray diffraction (XRD) for evaluating the spatial structure; Fourier transform infrared spectroscopy (FTIR) for getting information about the vibrational modes; scanning electron microscopy with dispersive Xray spectroscopy

  15. Quo Vadis the B.A. degree: Perceptions and visions1

    Directory of Open Access Journals (Sweden)

    Annette L. Combrink

    1993-03-01

    Full Text Available Today is a very special day for all the graduates assembled to have a B.A. degree conferred on them. It is a day on which to celebrate the reward for hard work and for realized dreams. This is a very homogeneous group of people - in the sense that they will be receiving B.A. degrees, and for that reason it would be highly apposite to share some cherished thought and ideas about the B.A. degree.

  16. Gold nanoparticle-mediated (GNOME) laser perforation: a new method for a high-throughput analysis of gap junction intercellular coupling.

    Science.gov (United States)

    Begandt, Daniela; Bader, Almke; Antonopoulos, Georgios C; Schomaker, Markus; Kalies, Stefan; Meyer, Heiko; Ripken, Tammo; Ngezahayo, Anaclet

    2015-10-01

    The present report evaluates the advantages of using the gold nanoparticle-mediated laser perforation (GNOME LP) technique as a computer-controlled cell optoperforation to introduce Lucifer yellow (LY) into cells in order to analyze the gap junction coupling in cell monolayers. To permeabilize GM-7373 endothelial cells grown in a 24 multiwell plate with GNOME LP, a laser beam of 88 μm in diameter was applied in the presence of gold nanoparticles and LY. After 10 min to allow dye uptake and diffusion through gap junctions, we observed a LY-positive cell band of 179 ± 8 μm width. The presence of the gap junction channel blocker carbenoxolone during the optoperforation reduced the LY-positive band to 95 ± 6 μm. Additionally, a forskolin-related enhancement of gap junction coupling, recently found using the scrape loading technique, was also observed using GNOME LP. Further, an automatic cell imaging and a subsequent semi-automatic quantification of the images using a java-based ImageJ-plugin were performed in a high-throughput sequence. Moreover, the GNOME LP was used on cells such as RBE4 rat brain endothelial cells, which cannot be mechanically scraped as well as on three-dimensionally cultivated cells, opening the possibility to implement the GNOME LP technique for analysis of gap junction coupling in tissues. We conclude that the GNOME LP technique allows a high-throughput automated analysis of gap junction coupling in cells. Moreover this non-invasive technique could be used on monolayers that do not support mechanical scraping as well as on cells in tissue allowing an in vivo/ex vivo analysis of gap junction coupling.

  17. Vector magnetometry of Fe/Cr/Fe trilayers with biquadratic coupling

    International Nuclear Information System (INIS)

    Mansell, R; Petit, D; Fernández-Pacheco, A; Lee, J H; Chin, S-L; Lavrijsen, R; Cowburn, R P

    2017-01-01

    The magnetic reversal of epitaxial Fe/Cr/Fe trilayer samples grown on GaAs is studied. In wedged samples both long and short period coupling oscillations associated with Ruderman–Kittel–Kasuya–Yosida (RKKY) coupling in Cr are seen in the easy axis saturation fields. By using vector vibrating sample magnetometry and both longitudinal and transverse magneto-optical Kerr effect magnetometry we are able to determine the exact reversal path of both the magnetic layers. Changes in the reversal behavior are seen with sub-monolayer changes of the thickness of the Cr interlayer. The two main reversal paths are described in terms of whether the reversal is dominated by bilinear RKKY coupling, which leads to an antiparallel state at remanence or by biquadratic coupling which leads to a 90 degree alignment of layers at remanence. The changing reversal behaviour is discussed with respect to the possibility of using such systems for multilayer memory applications and, in particular, the limits on the required accuracy of the sample growth. (letter)

  18. Transient coupling relationships of the Holocene Australian monsoon

    Science.gov (United States)

    McRobie, F. H.; Stemler, T.; Wyrwoll, K.-H.

    2015-08-01

    The northwest Australian summer monsoon owes a notable degree of its interannual variability to interactions with other regional monsoon systems. Therefore, changes in the nature of these relationships may contribute to variability in monsoon strength over longer time scales. Previous attempts to evaluate how proxy records from the Indonesian-Australian monsoon region correspond to other records from the Indian and East Asian monsoon regions, as well as to El Niño-related proxy records, have been qualitative, relying on 'curve-fitting' methods. Here, we seek a quantitative approach for identifying coupling relationships between paleoclimate proxy records, employing statistical techniques to compute the interdependence of two paleoclimate time series. We verify the use of complex networks to identify coupling relationships between modern climate indices. This method is then extended to a set of paleoclimate proxy records from the Asian, Australasian and South American regions spanning the past 9000 years. The resulting networks demonstrate the existence of coupling relationships between regional monsoon systems on millennial time scales, but also highlight the transient nature of teleconnections during this period. In the context of the northwest Australian summer monsoon, we recognise a shift in coupling relationships from strong interhemispheric links with East Asian and ITCZ-related proxy records in the mid-Holocene to significantly weaker coupling in the later Holocene. Although the identified links cannot explain the underlying physical processes leading to coupling between regional monsoon systems, this method provides a step towards understanding the role that changes in teleconnections play in millennial-to orbital-scale climate variability.

  19. Dynamical analysis of highly excited molecular spectra

    Energy Technology Data Exchange (ETDEWEB)

    Kellman, M.E. [Univ. of Oregon, Eugene (United States)

    1993-12-01

    The goal of this program is new methods for analysis of spectra and dynamics of highly excited vibrational states of molecules. In these systems, strong mode coupling and anharmonicity give rise to complicated classical dynamics, and make the simple normal modes analysis unsatisfactory. New methods of spectral analysis, pattern recognition, and assignment are sought using techniques of nonlinear dynamics including bifurcation theory, phase space classification, and quantization of phase space structures. The emphasis is chaotic systems and systems with many degrees of freedom.

  20. Coupled Flow and Mechanics in Porous and Fractured Media*

    Science.gov (United States)

    Martinez, M. J.; Newell, P.; Bishop, J.

    2012-12-01

    Numerical models describing subsurface flow through deformable porous materials are important for understanding and enabling energy security and climate security. Some applications of current interest come from such diverse areas as geologic sequestration of anthropogenic CO2, hydro-fracturing for stimulation of hydrocarbon reservoirs, and modeling electrochemistry-induced swelling of fluid-filled porous electrodes. Induced stress fields in any of these applications can lead to structural failure and fracture. The ultimate goal of this research is to model evolving faults and fracture networks and flow within the networks while coupling to flow and mechanics within the intact porous structure. We report here on a new computational capability for coupling of multiphase porous flow with geomechanics including assessment of over-pressure-induced structural damage. The geomechanics is coupled to the flow via the variation in the fluid pore pressures, whereas the flow problem is coupled to mechanics by the concomitant material strains which alter the pore volume (porosity field) and hence the permeability field. For linear elastic solid mechanics a monolithic coupling strategy is utilized. For nonlinear elastic/plastic and fractured media, a segregated coupling is presented. To facilitate coupling with disparate flow and mechanics time scales, the coupling strategy allows for different time steps in the flow solve compared to the mechanics solve. If time steps are synchronized, the controller allows user-specified intra-time-step iterations. The iterative coupling is dynamically controlled based on a norm measuring the degree of variation in the deformed porosity. The model is applied for evaluation of the integrity of jointed caprock systems during CO2 sequestration operations. Creation or reactivation of joints can lead to enhanced pathways for leakage. Similarly, over-pressures can induce flow along faults. Fluid flow rates in fractures are strongly dependent on the

  1. NK sensitivity of neuroblastoma cells determined by a highly sensitive coupled luminescent method

    International Nuclear Information System (INIS)

    Ogbomo, Henry; Hahn, Anke; Geiler, Janina; Michaelis, Martin; Doerr, Hans Wilhelm; Cinatl, Jindrich

    2006-01-01

    The measurement of natural killer (NK) cells toxicity against tumor or virus-infected cells especially in cases with small blood samples requires highly sensitive methods. Here, a coupled luminescent method (CLM) based on glyceraldehyde-3-phosphate dehydrogenase release from injured target cells was used to evaluate the cytotoxicity of interleukin-2 activated NK cells against neuroblastoma cell lines. In contrast to most other methods, CLM does not require the pretreatment of target cells with labeling substances which could be toxic or radioactive. The effective killing of tumor cells was achieved by low effector/target ratios ranging from 0.5:1 to 4:1. CLM provides highly sensitive, safe, and fast procedure for measurement of NK cell activity with small blood samples such as those obtained from pediatric patients

  2. A 2-DOF microstructure-dependent model for the coupled torsion/bending instability of rotational nanoscanner

    Science.gov (United States)

    Keivani, M.; Abadian, N.; Koochi, A.; Mokhtari, J.; Abadyan, M.

    2016-10-01

    It has been well established that the physical performance of nanodevices might be affected by the microstructure. Herein, a two-degree-of-freedom model base on the modified couple stress theory is developed to incorporate the impact of microstructure in the torsion/bending coupled instability of rotational nanoscanner. Effect of microstructure dependency on the instability parameters is determined as a function of the microstructure parameter, bending/torsion coupling ratio, van der Waals force parameter and geometrical dimensions. It is found that the bending/torsion coupling substantially affects the stable behavior of the scanners especially those with long rotational beam elements. Impact of microstructure on instability voltage of the nanoscanner depends on coupling ratio and the conquering bending mode over torsion mode. This effect is more highlighted for higher values of coupling ratio. Depending on the geometry and material characteristics, the presented model is able to simulate both hardening behavior (due to microstructure) and softening behavior (due to torsion/bending coupling) of the nanoscanners.

  3. Determination of Dibutyltin in Sediments Using Isotope Dilution Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

    International Nuclear Information System (INIS)

    Yim, Yong Hyeon; Park, Ji Youn; Han, Myung Sub; Park, Mi Kyung; Kim, Byung Joo; Lim, Young Ran; Hwang, Eui Jin; So, Hun Young

    2005-01-01

    A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties

  4. Determination of Dibutyltin in Sediments Using Isotope Dilution Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yim, Yong Hyeon; Park, Ji Youn; Han, Myung Sub; Park, Mi Kyung; Kim, Byung Joo; Lim, Young Ran; Hwang, Eui Jin; So, Hun Young [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2005-03-15

    A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.

  5. Study of a charge-coupled device for high-energy-particle detection

    International Nuclear Information System (INIS)

    Bhuiya, A.H.

    1983-05-01

    This presentation is based on measurements made to evaluate the application of charge-coupled devices as detectors of high-energy particles. The experiment was performed with a Fairchild Linear 256-Cell CCD111 array (size 8μm x 17 μm/cell), utilizing a light source instead of a particle beam. It was observed that the minimum detectable signal was limited to approx. 488 electrons at -50 0 C, where the readout and exposure times were about 260 ms and 400 ms respectively. The transfer inefficiency of the CCD111 was determined to be approx. 10 -4 . It has been concluded that at a lower temperature (approx. -100 0 C) or with faster readout (approx. 10 ms), the CCD111 would be able to detect the total deposited energy of minimum-ionizing charged particles

  6. Emergent Ising degrees of freedom above a double-stripe magnetic ground state

    Science.gov (United States)

    Zhang, Guanghua; Flint, Rebecca

    2017-12-01

    Double-stripe magnetism [Q =(π /2 ,π /2 )] has been proposed as the magnetic ground state for both the iron-telluride and BaTi2Sb2O families of superconductors. Double-stripe order is captured within a J1-J2-J3 Heisenberg model in the regime J3≫J2≫J1 . Intriguingly, besides breaking spin-rotational symmetry, the ground-state manifold has three additional Ising degrees of freedom associated with bond ordering. Via their coupling to the lattice, they give rise to an orthorhombic distortion and to two nonuniform lattice distortions with wave vector (π ,π ) . Because the ground state is fourfold degenerate, modulo rotations in spin space, only two of these Ising bond order parameters are independent. Here, we introduce an effective field theory to treat all Ising order parameters, as well as magnetic order, and solve it within a large-N limit. All three transitions, corresponding to the condensations of two Ising bond order parameters and one magnetic order parameter are simultaneous and first order in three dimensions, but lower dimensionality, or equivalently weaker interlayer coupling, and weaker magnetoelastic coupling can split the three transitions, and in some cases allows for two separate Ising phase transitions above the magnetic one.

  7. Dynamical analysis for a scalar-tensor model with Gauss-Bonnet and non-minimal couplings

    Energy Technology Data Exchange (ETDEWEB)

    Granda, L.N.; Jimenez, D.F. [Universidad del Valle, Departamento de Fisica, Cali (Colombia)

    2017-10-15

    We study the autonomous system for a scalar-tensor model of dark energy with Gauss-Bonnet and non-minimal couplings. The critical points describe important stable asymptotic scenarios including quintessence, phantom and de Sitter attractor solutions. Two functional forms for the coupling functions and the scalar potential are considered: power-law and exponential functions of the scalar field. For the exponential functions the existence of stable quintessence, phantom or de Sitter solutions, allows for an asymptotic behavior where the effective Newtonian coupling becomes constant. The phantom solutions could be realized without appealing to ghost degrees of freedom. Transient inflationary and radiation-dominated phases can also be described. (orig.)

  8. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1996-05-01

    A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration was installed at a benign site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington. The composite barrier was emplaced beneath a 7,500 liter tank. The tank was chosen to simulate a typical DOE Complex waste form. The stresses induced on the waste form were evaluated during barrier construction. The barrier was constructed using conventional jet grouting techniques. Drilling was completed at a 45 degree angle to the ground, forming a conical shaped barrier with the waste form inside the cone. Two overlapping rows of cylindrical cement columns were grouted in a honeycomb fashion to form the secondary backdrop barrier layer. The primary barrier, a high molecular weight polymer manufactured by 3M Company, was then installed providing a relatively thin inner liner for the secondary barrier. The primary barrier was emplaced by panel jet grouting with a dual wall drill stem, two phase jet grouting system

  9. Comparison of two-stage thermophilic (68 degrees C/55 degrees C) anaerobic digestion with one-stage thermophilic (55 degrees C) digestion of cattle manure.

    Science.gov (United States)

    Nielsen, H B; Mladenovska, Z; Westermann, P; Ahring, B K

    2004-05-05

    A two-stage 68 degrees C/55 degrees C anaerobic degradation process for treatment of cattle manure was studied. In batch experiments, an increase of the specific methane yield, ranging from 24% to 56%, was obtained when cattle manure and its fractions (fibers and liquid) were pretreated at 68 degrees C for periods of 36, 108, and 168 h, and subsequently digested at 55 degrees C. In a lab-scale experiment, the performance of a two-stage reactor system, consisting of a digester operating at 68 degrees C with a hydraulic retention time (HRT) of 3 days, connected to a 55 degrees C reactor with 12-day HRT, was compared with a conventional single-stage reactor running at 55 degrees C with 15-days HRT. When an organic loading of 3 g volatile solids (VS) per liter per day was applied, the two-stage setup had a 6% to 8% higher specific methane yield and a 9% more effective VS-removal than the conventional single-stage reactor. The 68 degrees C reactor generated 7% to 9% of the total amount of methane of the two-stage system and maintained a volatile fatty acids (VFA) concentration of 4.0 to 4.4 g acetate per liter. Population size and activity of aceticlastic methanogens, syntrophic bacteria, and hydrolytic/fermentative bacteria were significantly lower in the 68 degrees C reactor than in the 55 degrees C reactors. The density levels of methanogens utilizing H2/CO2 or formate were, however, in the same range for all reactors, although the degradation of these substrates was significantly lower in the 68 degrees C reactor than in the 55 degrees C reactors. Temporal temperature gradient electrophoresis profiles (TTGE) of the 68 degrees C reactor demonstrated a stable bacterial community along with a less divergent community of archaeal species. Copyright 2004 Wiley Periodicals, Inc.

  10. Highly selective etching of silicon nitride to physical-vapor-deposited a-C mask in dual-frequency capacitively coupled CH2F2/H2 plasmas

    International Nuclear Information System (INIS)

    Kim, J. S.; Kwon, B. S.; Heo, W.; Jung, C. R.; Park, J. S.; Shon, J. W.; Lee, N.-E.

    2010-01-01

    A multilevel resist (MLR) structure can be fabricated based on a very thin amorphous carbon (a-C) layer ( congruent with 80 nm) and Si 3 N 4 hard-mask layer ( congruent with 300 nm). The authors investigated the selective etching of the Si 3 N 4 layer using a physical-vapor-deposited (PVD) a-C mask in a dual-frequency superimposed capacitively coupled plasma etcher by varying the process parameters in the CH 2 F 2 /H 2 /Ar plasmas, viz., the etch gas flow ratio, high-frequency source power (P HF ), and low-frequency source power (P LF ). They found that under certain etch conditions they obtain infinitely high etch selectivities of the Si 3 N 4 layers to the PVD a-C on both the blanket and patterned wafers. The etch gas flow ratio played a critical role in determining the process window for infinitely high Si 3 N 4 /PVD a-C etch selectivity because of the change in the degree of polymerization. The etch results of a patterned ArF photoresisit/bottom antireflective coating/SiO x /PVD a-C/Si 3 N 4 MLR structure supported the idea of using a very thin PVD a-C layer as an etch-mask layer for the Si 3 N 4 hard-mask pattern with a pattern width of congruent with 80 nm and high aspect ratio of congruent with 5.

  11. Coupled modes, frequencies and fields of a dielectric resonator and a cavity using coupled mode theory

    Science.gov (United States)

    Elnaggar, Sameh Y.; Tervo, Richard; Mattar, Saba M.

    2014-01-01

    Probes consisting of a dielectric resonator (DR) inserted in a cavity are important integral components of electron paramagnetic resonance (EPR) spectrometers because of their high signal-to-noise ratio. This article studies the behavior of this system, based on the coupling between its dielectric and cavity modes. Coupled-mode theory (CMT) is used to determine the frequencies and electromagnetic fields of this coupled system. General expressions for the frequencies and field distributions are derived for both the resulting symmetric and anti-symmetric modes. These expressions are applicable to a wide range of frequencies (from MHz to THz). The coupling of cavities and DRs of various sizes and their resonant frequencies are studied in detail. Since the DR is situated within the cavity then the coupling between them is strong. In some cases the coupling coefficient, κ, is found to be as high as 0.4 even though the frequency difference between the uncoupled modes is large. This is directly attributed to the strong overlap between the fields of the uncoupled DR and cavity modes. In most cases, this improves the signal to noise ratio of the spectrometer. When the DR and the cavity have the same frequency, the coupled electromagnetic fields are found to contain equal contributions from the fields of the two uncoupled modes. This situation is ideal for the excitation of the probe through an iris on the cavity wall. To verify and validate the results, finite element simulations are carried out. This is achieved by simulating the coupling between a cylindrical cavity's TE011 and the dielectric insert's TE01δ modes. Coupling between the modes of higher order is also investigated and discussed. Based on CMT, closed form expressions for the fields of the coupled system are proposed. These expressions are crucial in the analysis of the probe's performance.

  12. Coupling of (ultra- relativistic atomic nuclei with photons

    Directory of Open Access Journals (Sweden)

    M. Apostol

    2013-11-01

    Full Text Available The coupling of photons with (ultra- relativistic atomic nuclei is presented in two particular circumstances: very high electromagnetic fields and very short photon pulses. We consider a typical situation where the (bare nuclei (fully stripped of electrons are accelerated to energies ≃ 1 TeV per nucleon (according to the state of the art at LHC, for instance and photon sources like petawatt lasers ≃ 1 eV-radiation (envisaged by ELI-NP project, for instance, or free-electron laser ≃ 10 keV-radiation, or synchrotron sources, etc. In these circumstances the nuclear scale energy can be attained, with very high field intensities. In particular, we analyze the nuclear transitions induced by the radiation, including both one- and two-photon proceses, as well as the polarization-driven transitions which may lead to giant dipole resonances. The nuclear (electrical polarization concept is introduced. It is shown that the perturbation theory for photo-nuclear reactions is applicable, although the field intensity is high, since the corresponding interaction energy is low and the interaction time (pulse duration is short. It is also shown that the description of the giant nuclear dipole resonance requires the dynamics of the nuclear electrical polarization degrees of freedom.

  13. RF and microwave coupled-line circuits

    CERN Document Server

    Mongia, R K; Bhartia, P; Hong, J; Gupta, K C

    2007-01-01

    This extensively revised edition of the 1999 Artech House classic, RF and Microwave Coupled-Line Circuits, offers you a thoroughly up-to-date understanding of coupled line fundamentals, explaining their applications in designing microwave and millimeter-wave components used in today's communications, microwave, and radar systems. The Second Edition includes a wealth of new material, particularly relating to applications. You find brand new discussions on a novel simple design technique for multilayer coupled circuits, high pass filters using coupled lines, software packages used for filter des

  14. Is self-disclosure in couples coping with cancer associated with improvement in depressive symptoms?

    NARCIS (Netherlands)

    Hagedoorn, Mariet; Puterman, Eli; Sanderman, Robbert; Wiggers, Theo; Baas, Peter C.; van Haastert, Michiel; DeLongis, Anita; van, Haastert M.

    2011-01-01

    Objective: This study examined associations between the degree of self-disclosure and changes in depressive symptoms in couples coping with colorectal cancer. Method: Sixty-four newly diagnosed patients and their partners completed a measure of depressive symptoms (Center of Epidemiologic Studies

  15. Oxidative coupling polymerization in a Langmuir monolayer of octadecyl 3,5-diaminobenzoate

    NARCIS (Netherlands)

    Kimkes, P.; Sohling, U.; Oostergetel, G.T.; Schouten, A.J.

    1996-01-01

    In a Langmuir monolayer of the surface active monomer octadecyl 3,5-diaminobenzoate (ODDB), stabilized at a surface pressure of 10 mN/m and a temperature of 23.7 degrees C at the air-water interface, oxidative coupling polymerization occurs when copper(II) chloride was added or already was present

  16. The Top 100: Graduate Degrees Conferred

    Science.gov (United States)

    Borden, Victor M. H.

    2011-01-01

    Recently, some critics and policymakers have started to question the value of a college education given the increasing costs of attending and the commensurate high debt levels of college graduates. Past and present studies also demonstrate that the average value masks important variation by degree level and field of study. This paper focuses on…

  17. Some results on the neutron transport and the coupling of equations; Quelques resultats sur le transport neutronique et le couplage d`equations

    Energy Technology Data Exchange (ETDEWEB)

    Bal, G. [Electricite de France (EDF), Direction des Etudes et Recherches, 92 - Clamart (France)

    1997-12-31

    Neutron transport in nuclear reactors is well modeled by the linear Boltzmann transport equation. Its resolution is relatively easy but very expensive. To achieve whole core calculations, one has to consider simpler models, such as diffusion or homogeneous transport equations. However, the solutions may become inaccurate in particular situations (as accidents for instance). That is the reason why we wish to solve the equations on small area accurately and more coarsely on the remaining part of the core. It is than necessary to introduce some links between different discretizations or modelizations. In this note, we give some results on the coupling of different discretizations of all degrees of freedom of the integral-differential neutron transport equation (two degrees for the angular variable, on for the energy component, and two or three degrees for spatial position respectively in 2D (cylindrical symmetry) and 3D). Two chapters are devoted to the coupling of discrete ordinates methods (for angular discretization). The first one is theoretical and shows the well posing of the coupled problem, whereas the second one deals with numerical applications of practical interest (the results have been obtained from the neutron transport code developed at the R and D, which has been modified for introducing the coupling). Next, we present the nodal scheme RTN0, used for the spatial discretization. We show well posing results for the non-coupled and the coupled problems. At the end, we deal with the coupling of energy discretizations for the multigroup equations obtained by homogenization. Some theoretical results of the discretization of the velocity variable (well-posing of problems), which do not deal directly with the purposes of coupling, are presented in the annexes. (author). 34 refs.

  18. A cAMP Biosensor-Based High-Throughput Screening Assay for Identification of Gs-Coupled GPCR Ligands and Phosphodiesterase Inhibitors

    DEFF Research Database (Denmark)

    Vedel, Line; Bräuner-Osborne, Hans; Mathiesen, Jesper Mosolff

    2015-01-01

    Cyclic adenosine 3',5'-monophosphate (cAMP) is an important second messenger, and quantification of intracellular cAMP levels is essential in studies of G protein-coupled receptors (GPCRs). The intracellular cAMP levels are regulated by the adenylate cyclase (AC) upon activation of either Gs- or ...... also observed for the other representative Gs-coupled GPCRs tested, GLP-1R and GlucagonR. The FRET-based cAMP biosensor assay is robust, reproducible, and inexpensive with good Z factors and is highly applicable for HTS....

  19. Acoustic emission analysis coupled with thermogravimetric experiments dedicated to high temperature corrosion studies on metallic alloys

    International Nuclear Information System (INIS)

    Serris, Eric; Al Haj, Omar; Peres, Veronique; Cournil, Michel; Kittel, Jean; Grosjean, Francois; Ropital, Francois

    2014-01-01

    High temperature corrosion of metallic alloys (like iron, nickel, zirconium alloys) can damage equipment of many industrial fields (refinery, petrochemical, nuclear..). Acoustic emission (AE) is an interesting method owing to its sensitivity and its non-destructive aspect to quantify the level of damage in use of these alloys under various environmental conditions. High temperature corrosive phenomena create stresses in the materials; the relaxation by cracks of these stresses can be recorded and analyzed using the AE system. The goal of our study is to establish an acoustic signals database which assigns the acoustic signals to the specific corrosion phenomena. For this purpose, thermogravimetric analysis (TGA) is coupled with acoustic emission (AE) devices. The oxidation of a zirconium alloy, zircaloy-4, is first studied using thermogravimetric experiment coupled to acoustic emission analysis at 900 C. An inward zirconium oxide scale, preliminary dense, then porous, grow during the isothermal isobaric step. The kinetic rate increases significantly after a kinetic transition (breakaway). This acceleration occurs with an increase of acoustic emission activity. Most of the acoustic emission bursts are recorded after the kinetic transition. Acoustic emission signals are also observed during the cooling of the sample. AE numerical treatments (using wavelet transform) completed by SEM microscopy characterizations allows us to distinguish the different populations of cracks. Metal dusting represents also a severe form of corrosive degradation of metal alloy. Iron metal dusting corrosion is studied by AE coupled with TGA at 650 C under C 4 H 10 + H 2 + He atmosphere. Acoustic emission signals are detected after a significant increase of the sample mass.

  20. Effects of c-axis Josephson coupling on dissipation, flux dynamics and the mechanism of high-Tc superconductivity

    International Nuclear Information System (INIS)

    Gray, K.E.; Hettinger, J.D.

    1995-01-01

    Measurements of the c-axis transport in highly anisotropic HTS materials strongly indicate that Josephson coupling is involved. This conclusion affects various properties of the HTS cuprates, including the irreversibility behavior for transport in the ab planes, the direct c-axis transport and potentially the mechanism of Cooper pairing