Directory of Open Access Journals (Sweden)
C.G. Ozoegwu
2016-01-01
Full Text Available The general least squares model for milling process state term is presented. A discrete map for milling stability analysis that is based on the third-order case of the presented general least squares milling state term model is first studied and compared with its third-order counterpart that is based on the interpolation theory. Both numerical rate of convergence and chatter stability results of the two maps are compared using the single degree of freedom (1DOF milling model. The numerical rate of convergence of the presented third-order model is also studied using the two degree of freedom (2DOF milling process model. Comparison gave that stability results from the two maps agree closely but the presented map demonstrated reduction in number of needed calculations leading to about 30% savings in computational time (CT. It is seen in earlier works that accuracy of milling stability analysis using the full-discretization method rises from first-order theory to second-order theory and continues to rise to the third-order theory. The present work confirms this trend. In conclusion, the method presented in this work will enable fast and accurate computation of stability diagrams for use by machinists.
International Nuclear Information System (INIS)
Tian, Si-Cong; Tong, Cun-Zhu; Zhang, Jin-Long; Shan, Xiao-Nan; Fu, Xi-Hong; Zeng, Yu-Gang; Qin, Li; Ning, Yong-Qiang; Wan, Ren-Gang
2015-01-01
The optical bistability of a triangular quantum dot molecules embedded inside a unidirectional ring cavity is studied. The type, the threshold and the hysteresis loop of the optical bistability curves can be modified by the tunneling parameters, as well as the probe laser field. The linear and nonlinear susceptibilities of the medium are also studied to interpret the corresponding results. The physical interpretation is that the tunneling can induce the quantum interference, which modifies the linear and the nonlinear response of the medium. As a consequence, the characteristics of the optical bistability are changed. The scheme proposed here can be utilized for optimizing and controlling the optical switching process
Indian Academy of Sciences (India)
N. Centre for Advanced Scientific Research, Bangalore 560 064, India. 2Indian Institute of ... for rational functions φ with poles off R. In [5,16], Koplienko's trace formula was derived ... be a sequence of complex numbers such that ..... Again if we set the sum of the second and fourth term inside the integral in (2.3) to be. I2 ≡.
Novel third-order Lovelock wormhole solutions
Mehdizadeh, Mohammad Reza; Lobo, Francisco S. N.
2016-06-01
In this work, we consider wormhole geometries in third-order Lovelock gravity and investigate the possibility that these solutions satisfy the energy conditions. In this framework, by applying a specific equation of state, we obtain exact wormhole solutions, and by imposing suitable values for the parameters of the theory, we find that these geometries satisfy the weak energy condition in the vicinity of the throat, due to the presence of higher-order curvature terms. Finally, we trace out a numerical analysis, by assuming a specific redshift function, and find asymptotically flat solutions that satisfy the weak energy condition throughout the spacetime.
Optofluidic third order distributed feedback dye laser
DEFF Research Database (Denmark)
Gersborg-Hansen, Morten; Kristensen, Anders
2006-01-01
which has a refractive index lower than that of the polymer. In combination with a third order DFB grating, formed by the array of nanofluidic channels, this yields a low threshold for lasing. The laser is straightforward to integrate on lab-on-a-chip microsystems where coherent, tunable light......This letter describes the design and operation of a polymer-based third order distributed feedback (DFB) microfluidic dye laser. The device relies on light confinement in a nanostructured polymer film where an array of nanofluidic channels is filled by capillary action with a liquid dye solution...
Third order differential equations with delay
Directory of Open Access Journals (Sweden)
Petr Liška
2015-05-01
Full Text Available In this paper, we study the oscillation and asymptotic properties of solutions of certain nonlinear third order differential equations with delay. In particular, we extend results of I. Mojsej (Nonlinear Analysis 68, 2008 and we improve conditions on the property B of N. Parhi and S. Padhi (Indian J. Pure Appl. Math., 33, 2002.
Decay ratio for third order Brownian oscillators
International Nuclear Information System (INIS)
Konno, H.; Kanemoto, S.
1998-01-01
We have obtained the analytical expressions of the decay ratios for two types of third order Brownian oscillators which are generalizations of the second order Brownian oscillator driven by the Gaussian-white noise. The resulting expressions will provide us useful baseline information for more complicated practical problems and their applications
Transposes, L-Eigenvalues and Invariants of Third Order Tensors
Qi, Liqun
2017-01-01
Third order tensors have wide applications in mechanics, physics and engineering. The most famous and useful third order tensor is the piezoelectric tensor, which plays a key role in the piezoelectric effect, first discovered by Curie brothers. On the other hand, the Levi-Civita tensor is famous in tensor calculus. In this paper, we study third order tensors and (third order) hypermatrices systematically, by regarding a third order tensor as a linear operator which transforms a second order t...
Optical nonclassicality test based on third-order intensity correlations
Rigovacca, L.; Kolthammer, W. S.; Di Franco, C.; Kim, M. S.
2018-03-01
We develop a nonclassicality criterion for the interference of three delayed, but otherwise identical, light fields in a three-mode Bell interferometer. We do so by comparing the prediction of quantum mechanics with those of a classical framework in which independent sources emit electric fields with random phases. In particular, we evaluate third-order correlations among output intensities as a function of the delays, and show how the presence of a correlation revival for small delays cannot be explained by the classical model of light. The observation of a revival is thus a nonclassicality signature, which can be achieved only by sources with a photon-number statistics that is highly sub-Poissonian. Our analysis provides strong evidence for the nonclassicality of the experiment discussed by Menssen et al. [Phys. Rev. Lett. 118, 153603 (2017), 10.1103/PhysRevLett.118.153603], and shows how a collective "triad" phase affects the interference of any three or more light fields, irrespective of their quantum or classical character.
Third-order optical intensity correlation measurements of pseudo-thermal light
International Nuclear Information System (INIS)
Chen Xi-Hao; Wu Wei; Meng Shao-Ying; Li Ming-Fei
2014-01-01
Third-order Hanbrury Brown—Twiss and double-slit interference experiments with a pseudo-thermal light are performed by recording intensities in single, double and triple optical paths, respectively. The experimental results verifies the theoretical prediction that the indispensable condition for achieving a interference pattern or ghost image in Nth-order intensity correlation measurements is the synchronous detection of the same light field by each reference detector, no matter the intensities recorded in one, or two, or N optical paths. It is shown that, when the reference detectors are scanned in the opposite directions, the visibility and resolution of the third-order spatial correlation function of thermal light is much better than that scanned in the same direction, but it is no use for obtaining the Nth-order interference pattern or ghost image in the thermal Nth-order interference or ghost imaging. (general)
Some third order rotatable designs in five dimensions | Mutiso | East ...
African Journals Online (AJOL)
... performed according to our dimensional designs need not be discarded. These deisgns require a smaller number of points than most of the available five dimensional third order rotatable designs. Keywords: third order; rotatable designs; four dimensions; five dimensions; sequential > East African Journal of Statistics Vol.
Application of third order stochastic dominance algorithm in investments ranking
Directory of Open Access Journals (Sweden)
Lončar Sanja
2012-01-01
Full Text Available The paper presents the use of third order stochastic dominance in ranking Investment alternatives, using TSD algorithms (Levy, 2006for testing third order stochastic dominance. The main goal of using TSD rule is minimization of efficient investment set for investor with risk aversion, who prefers more money and likes positive skew ness.
Ghost imaging with third-order correlated thermal light
International Nuclear Information System (INIS)
Ou, L-H; Kuang, L-M
2007-01-01
In this paper, we propose a ghost imaging scheme with third-order correlated thermal light. We show that it is possible to produce the spatial information of an object at two different places in a nonlocal fashion by means of a third-order correlated imaging process with a third-order correlated thermal source and third-order correlation measurement. Concretely, we propose a protocol to create two ghost images at two different places from one object. This protocol involves two optical configurations. We derive the Gaussian thin lens equations and plot the geometrical optics of the ghost imaging processes for the two configurations. It is indicated that third-order correlated ghost imaging with thermal light exhibits richer correlated imaging effects than second-order correlated ghost imaging with thermal light
Embedded solitons in the third-order nonlinear Schroedinger equation
International Nuclear Information System (INIS)
Pal, Debabrata; Ali, Sk Golam; Talukdar, B
2008-01-01
We work with a sech trial function with space-dependent soliton parameters and envisage a variational study for the nonlinear Schoedinger (NLS) equation in the presence of third-order dispersion. We demonstrate that the variational equations for pulse evolution in this NLS equation provide a natural basis to derive a potential model which can account for the existence of a continuous family of embedded solitons supported by the third-order NLS equation. Each member of the family is parameterized by the propagation velocity and co-efficient of the third-order dispersion
Proactive Interference in Short-Term Recognition and Recall Memory
Dillon, Richard F.; Petrusic, William M.
1972-01-01
Purpose of study was to (a) compare the rate of increase of proactive interference over the first few trials under recall and recognition memory test conditions, (2) determine the effects of two types of distractors on short-term recognition, and (3) test memory after proactive interference had reached a stable level under each of three test…
Third order TRANSPORT with MAD [Methodical Accelerator Design] input
International Nuclear Information System (INIS)
Carey, D.C.
1988-01-01
This paper describes computer-aided design codes for particle accelerators. Among the topics discussed are: input beam description; parameters and algebraic expressions; the physical elements; beam lines; operations; and third-order transfer matrix
Anisotropic Third-Order Regularization for Sparse Digital Elevation Models
Lellmann, Jan; Morel, Jean-Michel; Schö nlieb, Carola-Bibiane
2013-01-01
features of the contours while ensuring smoothness across level lines. We propose an anisotropic third-order model and an efficient method to adaptively estimate both the surface and the anisotropy. Our experiments show that the approach outperforms AMLE
Oscillation criteria for third order delay nonlinear differential equations
Directory of Open Access Journals (Sweden)
E. M. Elabbasy
2012-01-01
via comparison with some first differential equations whose oscillatory characters are known. Our results generalize and improve some known results for oscillation of third order nonlinear differential equations. Some examples are given to illustrate the main results.
Synthesis, characterization and third-order nonlinear optical ...
Indian Academy of Sciences (India)
2016-09-20
Sep 20, 2016 ... the past, several strategies have been evolved to enhance the third-order nonlinear ..... retical fit using the formulation given in ref. [22]. Fit param- ..... Acknowledgement. The corresponding author acknowledges the financial.
Hojman's theorem of the third-order ordinary differential equation
International Nuclear Information System (INIS)
Hong-Sheng, Lü; Hong-Bin, Zhang; Shu-Long, Gu
2009-01-01
This paper extends Hojman's conservation law to the third-order differential equation. A new conserved quantity is constructed based on the Lie group of transformation generators of the equations of motion. The generators contain variations of the time and generalized coordinates. Two independent non-trivial conserved quantities of the third-order ordinary differential equation are obtained. A simple example is presented to illustrate the applications of the results. (general)
Dynamics of platicons due to third-order dispersion
Lobanov, Valery E.; Cherenkov, Artem V.; Shitikov, Artem E.; Bilenko, Igor A.; Gorodetsky, Michael L.
2017-07-01
Dynamics of platicons caused by the third-order dispersion is studied. It is shown that under the influence of the third-order dispersion platicons obtain angular velocity depending both on dispersion and on detuning value. A method of tuning of platicon associated optical frequency comb repetition rate is proposed. Contribution to the Topical Issue "Theory and Applications of the Lugiato-Lefever Equation", edited by Yanne K. Chembo, Damia Gomila, Mustapha Tlidi, Curtis R. Menyuk.
Extension of relativistic dissipative hydrodynamics to third order
International Nuclear Information System (INIS)
El, Andrej; Xu Zhe; Greiner, Carsten
2010-01-01
Following the procedure introduced by Israel and Stewart, we expand the entropy current up to the third order in the shear stress tensor π αβ and derive a novel third-order evolution equation for π αβ . This equation is solved for the one-dimensional Bjorken boost-invariant expansion. The scaling solutions for various values of the shear viscosity to the entropy density ratio η/s are shown to be in very good agreement with those obtained from kinetic transport calculations. For the pressure isotropy starting with 1 at τ 0 =0.4 fm/c, the third-order corrections to Israel-Stewart theory are approximately 10% for η/s=0.2 and more than a factor of 2 for η/s=3. We also estimate all higher-order corrections to Israel-Stewart theory and demonstrate their importance in describing highly viscous matters.
Convergence of third order correlation energy in atoms and molecules.
Kahn, Kalju; Granovsky, Alex A; Noga, Jozef
2007-01-30
We have investigated the convergence of third order correlation energy within the hierarchies of correlation consistent basis sets for helium, neon, and water, and for three stationary points of hydrogen peroxide. This analysis confirms that singlet pair energies converge much slower than triplet pair energies. In addition, singlet pair energies with (aug)-cc-pVDZ and (aug)-cc-pVTZ basis sets do not follow a converging trend and energies with three basis sets larger than aug-cc-pVTZ are generally required for reliable extrapolations of third order correlation energies, making so the explicitly correlated R12 calculations preferable.
Third-order aberration-free ion-optical system for an electromagnetic isotope separator
International Nuclear Information System (INIS)
Chavet, I.
1982-12-01
The essential qualities required of a production isotope separator are high output and high enrichment factor. For this purpose, the imaging system should have as little geometric aberration as possible. In the proposed system, consisting of a homogeneous sector-type analyzing magnet, the beam is crossed in the axial direction at the entrance boundary of the magnetic field and the incidence to this boundary is normal. It is shown that for this case all radial aberrations to the ''practical'' third order can be eliminated provided four optical conditions are satisfied: two related to heterogeneous aberration terms in addition to the two conditions related to the second and third order homogeneous aperture aberration terms. The resulting equations take into account the magnetic fringe-field effects to the third order. (author)
An approximation to the interference term using Frobenius Method
Energy Technology Data Exchange (ETDEWEB)
Palma, Daniel A.P.; Martinez, Aquilino S.; Silva, Fernando C. da [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear; E-mail: aquilino@lmp.ufrj.br
2007-07-01
An analytical approximation of the interference term {chi}(x,{xi}) is proposed. The approximation is based on the differential equation to {chi}(x,{xi}) using the Frobenius method and the parameter variation. The analytical expression of the {chi}(x,{xi}) obtained in terms of the elementary functions is very simple and precise. In this work one applies the approximations to the Doppler broadening functions and to the interference term in determining the neutron cross sections. Results were validated for the resonances of the U{sup 238} isotope for different energies and temperature ranges. (author)
An approximation to the interference term using Frobenius Method
International Nuclear Information System (INIS)
Palma, Daniel A.P.; Martinez, Aquilino S.; Silva, Fernando C. da
2007-01-01
An analytical approximation of the interference term χ(x,ξ) is proposed. The approximation is based on the differential equation to χ(x,ξ) using the Frobenius method and the parameter variation. The analytical expression of the χ(x,ξ) obtained in terms of the elementary functions is very simple and precise. In this work one applies the approximations to the Doppler broadening functions and to the interference term in determining the neutron cross sections. Results were validated for the resonances of the U 238 isotope for different energies and temperature ranges. (author)
Taub-NUT black holes in third order Lovelock gravity
International Nuclear Information System (INIS)
Hendi, S.H.; Dehghani, M.H.
2008-01-01
We consider the existence of Taub-NUT solutions in third order Lovelock gravity with cosmological constant, and obtain the general form of these solutions in eight dimensions. We find that, as in the case of Gauss-Bonnet gravity and in contrast with the Taub-NUT solutions of Einstein gravity, the metric function depends on the specific form of the base factors on which one constructs the circle fibration. Thus, one may say that the independence of the NUT solutions on the geometry of the base space is not a robust feature of all generally covariant theories of gravity and is peculiar to Einstein gravity. We find that when Einstein gravity admits non-extremal NUT solutions with no curvature singularity at r=N, then there exists a non-extremal NUT solution in third order Lovelock gravity. In 8-dimensional spacetime, this happens when the metric of the base space is chosen to be CP 3 . Indeed, third order Lovelock gravity does not admit non-extreme NUT solutions with any other base space. This is another property which is peculiar to Einstein gravity. We also find that the third order Lovelock gravity admits extremal NUT solution when the base space is T 2 xT 2 xT 2 or S 2 xT 2 xT 2 . We have extended these observations to two conjectures about the existence of NUT solutions in Lovelock gravity in any even-dimensional spacetime
Third-Order Matching in the Polymorphic Lambda Calculus
Springintveld, J.
We show that it is decidable whether a third-order matching problem in the polymorphic lambda calculus has a solution. The proof is constructive in the sense that an algorithm can be extracted from it that, given such a problem, returns a substitution if it has a solution and fail otherwise.
A new third order rotatable design in five dimensions through ...
African Journals Online (AJOL)
Experiments of this kind could be widely applicable in human medicine, veterinary medicine, agriculture and in general, product research-innovation development for optimum resource utilisation based industrialisation process in line with the Kenya Vision 2030. In this paper, a third order rotatable design in five dimensions ...
An accurate scheme by block method for third order ordinary ...
African Journals Online (AJOL)
problems of ordinary differential equations is presented in this paper. The approach of collocation approximation is adopted in the derivation of the scheme and then the scheme is applied as simultaneous integrator to special third order initial value problem of ordinary differential equations. This implementation strategy is ...
MPDATA: Third-order accuracy for variable flows
Waruszewski, Maciej; Kühnlein, Christian; Pawlowska, Hanna; Smolarkiewicz, Piotr K.
2018-04-01
This paper extends the multidimensional positive definite advection transport algorithm (MPDATA) to third-order accuracy for temporally and spatially varying flows. This is accomplished by identifying the leading truncation error of the standard second-order MPDATA, performing the Cauchy-Kowalevski procedure to express it in a spatial form and compensating its discrete representation-much in the same way as the standard MPDATA corrects the first-order accurate upwind scheme. The procedure of deriving the spatial form of the truncation error was automated using a computer algebra system. This enables various options in MPDATA to be included straightforwardly in the third-order scheme, thereby minimising the implementation effort in existing code bases. Following the spirit of MPDATA, the error is compensated using the upwind scheme resulting in a sign-preserving algorithm, and the entire scheme can be formulated using only two upwind passes. Established MPDATA enhancements, such as formulation in generalised curvilinear coordinates, the nonoscillatory option or the infinite-gauge variant, carry over to the fully third-order accurate scheme. A manufactured 3D analytic solution is used to verify the theoretical development and its numerical implementation, whereas global tracer-transport benchmarks demonstrate benefits for chemistry-transport models fundamental to air quality monitoring, forecasting and control. A series of explicitly-inviscid implicit large-eddy simulations of a convective boundary layer and explicitly-viscid simulations of a double shear layer illustrate advantages of the fully third-order-accurate MPDATA for fluid dynamics applications.
Third-order theory for multi-directional irregular waves
DEFF Research Database (Denmark)
Madsen, Per A.; Fuhrman, David R.
2012-01-01
A new third-order solution for multi-directional irregular water waves in finite water depth is presented. The solution includes explicit expressions for the surface elevation, the amplitude dispersion and the vertical variation of the velocity potential. Expressions for the velocity potential at...
Third-order monochromatic aberrations via Fermat's principle
International Nuclear Information System (INIS)
Marasco, A.; Romano, A.
2006-01-01
By Fermat's principle and particular optical paths, which are not rays, a new aberration function is introduced. This function allows to derive, without resorting to the whole Hamiltonian formalism, the third-order geometrical aberrations of an optical system with a symmetry of revolution
Energy Technology Data Exchange (ETDEWEB)
Mark, J. Abraham Hudson, E-mail: a.john.peter@gmail.com; Peter, A. John, E-mail: a.john.peter@gmail.com [Dept. of Physics, SSM Institute of Engineering and Technology, Dindigul-624002 (India)
2014-04-24
Third order susceptibility of third order harmonic generation is investigated in a Zn{sub 0.1}Mg{sub 0.9}Se/Zn{sub 0.8}Mg{sub 0.2}Se/Zn{sub 0.1}Mg{sub 0.9}Se quantum well in the presence of magnetic field strength. The confinement potential is considered as the addition of energy offsets of the conduction band (or valence band) and the strain-induced potential in our calculations. The material dependent effective mass is followed throughout the computation because it has a high influence on the electron energy levels in low dimensional semiconductor systems.
Instability of black strings in the third-order Lovelock theory
Giacomini, Alex; Henríquez-Báez, Carla; Lagos, Marcela; Oliva, Julio; Vera, Aldo
2016-05-01
We show that homogeneous black strings of third-order Lovelock theory are unstable under s-wave perturbations. This analysis is done in dimension D =9 , which is the lowest dimension that allows the existence of homogeneous black strings in a theory that contains only the third-order Lovelock term in the Lagrangian. As is the case in general relativity, the instability is produced by long wavelength perturbations and it stands for the perturbative counterpart of a thermal instability. We also provide a comparative analysis of the instabilities of black strings at a fixed radius in general relativity, Gauss-Bonnet, and third-order Lovelock theories. We show that the minimum critical wavelength that triggers the instability grows with the power of the curvature defined in the Lagrangian. The maximum exponential growth during the time of the perturbation is the largest in general relativity and it decreases with the number of curvatures involved in the Lagrangian.
The effect of scattering interference term on the practical width
International Nuclear Information System (INIS)
Martins do Amaral, C.; Martinez, A.S.
2001-01-01
The practical width Γ p has an important application in the characterization of the resonance type for the calculation of neutron average cross sections. Previous treatments ignore the interference term χζ,x for the Doppler broadening function in the practical width calculation. In the present paper, a rational approximation for the χζ,x function is derived, using a modified asymptotic Pade method. A new approximation for Γ p is obtained. The results which are presented here provide evidence that the practical width as a function of temperature varies considerably with the inclusion of the interference term χζ,x
Memory Reactivation Enables Long-Term Prevention of Interference.
Herszage, Jasmine; Censor, Nitzan
2017-05-22
The ability of the human brain to successively learn or perform two competing tasks constitutes a major challenge in daily function. Indeed, exposing the brain to two different competing memories within a short temporal offset can induce interference, resulting in deteriorated performance in at least one of the learned memories [1-4]. Although previous studies have investigated online interference and its effects on performance [5-13], whether the human brain can enable long-term prevention of future interference is unknown. To address this question, we utilized the memory reactivation-reconsolidation framework [2, 12] stemming from studies at the synaptic level [14-17], according to which reactivation of a memory enables its update. In a set of experiments, using the motor sequence learning task [18] we report that a unique pairing of reactivating the original memory (right hand) in synchrony with novel memory trials (left hand) prevented future interference between the two memories. Strikingly, these effects were long-term and observed a month following reactivation. Further experiments showed that preventing future interference was not due to practice per se, but rather specifically depended on a limited time window induced by reactivation of the original memory. These results suggest a mechanism according to which memory reactivation enables long-term prevention of interference, possibly by creating an updated memory trace integrating original and novel memories during the reconsolidation time window. The opportunity to induce a long-term preventive effect on memories may enable the utilization of strategies optimizing normal human learning, as well as recovery following neurological insults. Copyright © 2017 Elsevier Ltd. All rights reserved.
Third-order gap plasmon based metasurfaces for visible light
DEFF Research Database (Denmark)
Deshpande, Rucha Anil; Pors, Anders; Bozhevolnyi, Sergey I.
2017-01-01
with different dimensions, to operate as a polarization beam splitter for linearly polarized light. The fabricated polarization beam splitter is characterized using a super-continuum light source at normal light incidence and found to exhibit a polarization contrast ratio of up to 40 dB near the design...... of the performance of polarization beam splitters based on third-order GSP resonance as well as other potential applications of the suggested approach....... by an optically thick gold film are calculated for the operation wavelength of 633 nm. Exploiting the occurrence of the third-order GSP resonance for nanobricks having their lengths close to 300 nm, we design the phase-gradient metasurface, representing an array of (450 x 2250 nm2) supercells made of 5 nanobricks...
Brown's TRANSPORT up to third order aberration by artificial intelligence
International Nuclear Information System (INIS)
Xia Jiawen; Xie Xi; Qiao Qingwen
1991-01-01
Brown's TRANSPORT is a first and second order matrix multiplication computer program intended for the design of accelerator beam transport systems, neglecting the third order aberration. Recently a new method was developed to derive analytically any order aberration coefficients of general charged particle optic system, applicable to any practical systems, such as accelerators, electron microscopes, lithographs, etc., including those unknown systems yet to be invented. An artificial intelligence program in Turbo Prolog was implemented on IBM-PC 286 or 386 machine to generate automatically the analytical expression of any order aberration coefficients of general charged particle optic system. Based on this new method and technique, Brown's TRANSPORT is extended beyond the second order aberration effects by artificial intelligence, outputing automatically all the analytical expressions up to the third order aberration coefficients
Brown's transport up to third order aberration by artificial intelligence
International Nuclear Information System (INIS)
Xia Jiawen; Xie Xi; Qiao Qingwen
1992-01-01
Brown's TRANSPORT is a first and second order matrix multiplication computer program intended for the design of accelerator beam transport systems, neglecting the third order aberration. Recently a new method was developed to derive analytically any order aberration coefficients of general charged particle optic system, applicable to any practical systems, such as accelerators, electron microscopes, lithographs, including those unknown systems yet to be invented. An artificial intelligence program in Turbo Prolog was implemented on IBM-PC 286 or 386 machine to generate automatically the analytical expression of any order aberration coefficients of general charged particle optic system. Based on this new method and technique, Brown's TRANSPORT is extended beyond the second order aberration effect by artificial intelligence, outputting automatically all the analytical expressions up to the third order aberration coefficients
Computer program 'TRIO' for third order calculation of ion trajectory
International Nuclear Information System (INIS)
Matsuo, Takekiyo; Matsuda, Hisashi; Fujita, Yoshitaka; Wollnik, H.
1976-01-01
A computer program for the calculation of ion trajectory is described. This program ''TRIO'' (Third Order Ion Optics) is applicable to any ion optical system consisting of drift spaces, cylindrical or toroidal electric sector fields, homogeneous or inhomogeneous magnetic sector fields, magnetic and electrostatic Q-lenses. The influence of the fringing field is taken into consideration. A special device is introduced to the method of matrix multiplication to shorten the calculation time and the required time proves to be about 40 times shorter than the ordinary method as a result. The trajectory calculation is possible to execute with accuracy up to third order. Any one of three dispersion bases, momentum, energy, mass and energy, is possible to be selected. Full LIST of the computer program and an example are given. (auth.)
Ultrafast third-order nonlinearity of silver nanospheres and nanodiscs
Energy Technology Data Exchange (ETDEWEB)
Jayabalan, J; Singh, Asha; Chari, Rama; Oak, Shrikant M [Ultrafast Studies Section, Laser Physics Application Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)
2007-08-08
We have measured and compared the absolute values of nonlinear susceptibility of colloidal solutions containing silver nanospheres and nanodiscs at their respective plasmon peaks using a femtosecond laser. The nonlinear process responsible for the laser-induced grating formation in the sample is determined to be of third order. The ratio between the third-order susceptibility (|{chi}{sup (3)}|) and the linear absorption coefficient ({alpha}) of the nanodiscs at 590 nm is three times than that of the similar ratio for nanospheres at 398 nm. Using a randomly oriented ellipsoidal model, we have shown that the increase in |{chi}{sup (3)}|/{alpha} for a nanodisc at 590 nm can be attributed to the change in the field enhancement factor with shape.
Ultrafast third-order nonlinearity of silver nanospheres and nanodiscs
International Nuclear Information System (INIS)
Jayabalan, J; Singh, Asha; Chari, Rama; Oak, Shrikant M
2007-01-01
We have measured and compared the absolute values of nonlinear susceptibility of colloidal solutions containing silver nanospheres and nanodiscs at their respective plasmon peaks using a femtosecond laser. The nonlinear process responsible for the laser-induced grating formation in the sample is determined to be of third order. The ratio between the third-order susceptibility (|χ (3) |) and the linear absorption coefficient (α) of the nanodiscs at 590 nm is three times than that of the similar ratio for nanospheres at 398 nm. Using a randomly oriented ellipsoidal model, we have shown that the increase in |χ (3) |/α for a nanodisc at 590 nm can be attributed to the change in the field enhancement factor with shape
A memristor-based third-order oscillator: beyond oscillation
Talukdar, Abdul Hafiz Ibne
2012-10-06
This paper demonstrates the first third-order autonomous linear time variant circuit realization that enhances parametric oscillation through the usage of memristor in conventional oscillators. Although the output has sustained oscillation, the linear features of the conventional oscillators become time dependent. The poles oscillate in nonlinear behavior due to the oscillation of memristor resistance. The mathematical formulas as well as SPICE simulations are introduced for the memristor-based phase shift oscillator showing a great matching.
Third-order susceptibility of gold for ultrathin layers
DEFF Research Database (Denmark)
Lysenko, Oleg; Bache, Morten; Lavrinenko, Andrei
2016-01-01
This Letter presents an experimental study of nonlinear plasmonic effects in gold-stripe waveguides. The optical characterization is performed by a picosecond laser and reveals two nonlinear effects related to propagation of long-range surface plasmon polaritons: nonlinear power transmission...... of plasmonic modes and spectral broadening of plasmonic modes. The experimental values of the third-order susceptibility of the gold layers are extracted. They exhibit a clear dependence on layer thickness. (C) 2016 Optical Society of America...
Experimental determination of third-order elastic constants of diamond.
Lang, J M; Gupta, Y M
2011-03-25
To determine the nonlinear elastic response of diamond, single crystals were shock compressed along the [100], [110], and [111] orientations to 120 GPa peak elastic stresses. Particle velocity histories and elastic wave velocities were measured by using laser interferometry. The measured elastic wave profiles were used, in combination with published acoustic measurements, to determine the complete set of third-order elastic constants. These constants represent the first experimental determination, and several differ significantly from those calculated by using theoretical models.
A memristor-based third-order oscillator: beyond oscillation
Talukdar, Abdul Hafiz Ibne; Radwan, Ahmed G.; Salama, Khaled N.
2012-01-01
This paper demonstrates the first third-order autonomous linear time variant circuit realization that enhances parametric oscillation through the usage of memristor in conventional oscillators. Although the output has sustained oscillation, the linear features of the conventional oscillators become time dependent. The poles oscillate in nonlinear behavior due to the oscillation of memristor resistance. The mathematical formulas as well as SPICE simulations are introduced for the memristor-based phase shift oscillator showing a great matching.
Energy Technology Data Exchange (ETDEWEB)
Yan, Hao-Peng; Liu, Wen-Biao, E-mail: wbliu@bnu.edu.cn
2016-08-10
Using Parikh–Wilczek tunneling framework, we calculate the tunneling rate from a Schwarzschild black hole under the third order WKB approximation, and then obtain the expressions for emission spectrum and black hole entropy to the third order correction. The entropy contains four terms including the Bekenstein–Hawking entropy, the logarithmic term, the inverse area term, and the square of inverse area term. In addition, we analyse the correlation between sequential emissions under this approximation. It is shown that the entropy is conserved during the process of black hole evaporation, which consists with the request of quantum mechanics and implies the information is conserved during this process. We also compare the above result with that of pure thermal spectrum case, and find that the non-thermal correction played an important role.
Third-order differential ladder operators and supersymmetric quantum mechanics
International Nuclear Information System (INIS)
Mateo, J; Negro, J
2008-01-01
Hierarchies of one-dimensional Hamiltonians in quantum mechanics admitting third-order differential ladder operators are studied. Each Hamiltonian has associated three-step Darboux (pseudo)-cycles and Painleve IV equations as a closure condition. The whole hierarchy is generated applying some operations on the cycles. These operations are investigated in the frame of supersymmetric quantum mechanics and mainly involve algebraic manipulations. A consistent geometric representation for the hierarchy and cycles is built that also helps in understanding the operations. Three kinds of hierarchies are distinguished and a realization based on the harmonic oscillator Hamiltonian is supplied, giving an interpretation for the spectral properties of the Hamiltonians of each hierarchy
Anisotropic Third-Order Regularization for Sparse Digital Elevation Models
Lellmann, Jan
2013-01-01
We consider the problem of interpolating a surface based on sparse data such as individual points or level lines. We derive interpolators satisfying a list of desirable properties with an emphasis on preserving the geometry and characteristic features of the contours while ensuring smoothness across level lines. We propose an anisotropic third-order model and an efficient method to adaptively estimate both the surface and the anisotropy. Our experiments show that the approach outperforms AMLE and higher-order total variation methods qualitatively and quantitatively on real-world digital elevation data. © 2013 Springer-Verlag.
Systems of conservation laws with third-order Hamiltonian structures
Ferapontov, Evgeny V.; Pavlov, Maxim V.; Vitolo, Raffaele F.
2018-02-01
We investigate n-component systems of conservation laws that possess third-order Hamiltonian structures of differential-geometric type. The classification of such systems is reduced to the projective classification of linear congruences of lines in P^{n+2} satisfying additional geometric constraints. Algebraically, the problem can be reformulated as follows: for a vector space W of dimension n+2 , classify n-tuples of skew-symmetric 2-forms A^{α } \\in Λ ^2(W) such that φ _{β γ }A^{β }\\wedge A^{γ }=0, for some non-degenerate symmetric φ.
Driven similarity renormalization group: Third-order multireference perturbation theory.
Li, Chenyang; Evangelista, Francesco A
2017-03-28
A third-order multireference perturbation theory based on the driven similarity renormalization group (DSRG-MRPT3) approach is presented. The DSRG-MRPT3 method has several appealing features: (a) it is intruder free, (b) it is size consistent, (c) it leads to a non-iterative algorithm with O(N 6 ) scaling, and (d) it includes reference relaxation effects. The DSRG-MRPT3 scheme is benchmarked on the potential energy curves of F 2 , H 2 O 2 , C 2 H 6 , and N 2 along the F-F, O-O, C-C, and N-N bond dissociation coordinates, respectively. The nonparallelism errors of DSRG-MRPT3 are consistent with those of complete active space third-order perturbation theory and multireference configuration interaction with singles and doubles and show significant improvements over those obtained from DSRG second-order multireference perturbation theory. Our efficient implementation of the DSRG-MRPT3 based on factorized electron repulsion integrals enables studies of medium-sized open-shell organic compounds. This point is demonstrated with computations of the singlet-triplet splitting (Δ ST =E T -E S ) of 9,10-anthracyne. At the DSRG-MRPT3 level of theory, our best estimate of the adiabatic Δ ST is 3.9 kcal mol -1 , a value that is within 0.1 kcal mol -1 from multireference coupled cluster results.
Criticality in third order lovelock gravity and butterfly effect
International Nuclear Information System (INIS)
Qaemmaqami, Mohammad M.
2018-01-01
We study third order Lovelock Gravity in D = 7 at the critical point which three (A)dS vacua degenerate into one. We see there is not propagating graviton at the critical point. And also we compute the butterfly velocity for this theory at the critical point by considering the shock wave solutions near horizon, this is important to note that although there is no propagating graviton at the critical point, due to boundary gravitons the butterfly velocity is non-zero. Finally we observe that the butterfly velocity for third order Lovelock Gravity at the critical point in D = 7 is less than the butterfly velocity for Einstein-Gauss-Bonnet Gravity at the critical point in D = 7 which is less than the butterfly velocity in D = 7 for Einstein Gravity, v B E.H > v B E.G.B > v B 3rdLovelock . Maybe we can conclude that by adding higher order curvature corrections to Einstein Gravity the butterfly velocity decreases. (orig.)
Effect of third-order aberrations on dynamic accommodation.
López-Gil, Norberto; Rucker, Frances J; Stark, Lawrence R; Badar, Mustanser; Borgovan, Theodore; Burke, Sean; Kruger, Philip B
2007-03-01
We investigate the potential for the third-order aberrations coma and trefoil to provide a signed cue to accommodation. It is first demonstrated theoretically (with some assumptions) that the point spread function is insensitive to the sign of spherical defocus in the presence of odd-order aberrations. In an experimental investigation, the accommodation response to a sinusoidal change in vergence (1-3D, 0.2Hz) of a monochromatic stimulus was obtained with a dynamic infrared optometer. Measurements were obtained in 10 young visually normal individuals with and without custom contact lenses that induced low and high values of r.m.s. trefoil (0.25, 1.03 microm) and coma (0.34, 0.94 microm). Despite variation between subjects, we did not find any statistically significant increase or decrease in the accommodative gain for low levels of trefoil and coma, although effects approached or reached significance for the high levels of trefoil and coma. Theoretical and experimental results indicate that the presence of Zernike third-order aberrations on the eye does not seem to play a crucial role in the dynamics of the accommodation response.
Criticality in third order lovelock gravity and butterfly effect
Energy Technology Data Exchange (ETDEWEB)
Qaemmaqami, Mohammad M. [Institute for Research in Fundamental Sciences (IPM), School of Particles and Accelerators, Tehran (Iran, Islamic Republic of)
2018-01-15
We study third order Lovelock Gravity in D = 7 at the critical point which three (A)dS vacua degenerate into one. We see there is not propagating graviton at the critical point. And also we compute the butterfly velocity for this theory at the critical point by considering the shock wave solutions near horizon, this is important to note that although there is no propagating graviton at the critical point, due to boundary gravitons the butterfly velocity is non-zero. Finally we observe that the butterfly velocity for third order Lovelock Gravity at the critical point in D = 7 is less than the butterfly velocity for Einstein-Gauss-Bonnet Gravity at the critical point in D = 7 which is less than the butterfly velocity in D = 7 for Einstein Gravity, v{sub B}{sup E.H} > v{sub B}{sup E.G.B} > v{sub B}{sup 3rdLovelock}. Maybe we can conclude that by adding higher order curvature corrections to Einstein Gravity the butterfly velocity decreases. (orig.)
Criticality in third order lovelock gravity and butterfly effect
Qaemmaqami, Mohammad M.
2018-01-01
We study third order Lovelock Gravity in D=7 at the critical point which three (A)dS vacua degenerate into one. We see there is not propagating graviton at the critical point. And also we compute the butterfly velocity for this theory at the critical point by considering the shock wave solutions near horizon, this is important to note that although there is no propagating graviton at the critical point, due to boundary gravitons the butterfly velocity is non-zero. Finally we observe that the butterfly velocity for third order Lovelock Gravity at the critical point in D=7 is less than the butterfly velocity for Einstein-Gauss-Bonnet Gravity at the critical point in D=7 which is less than the butterfly velocity in D = 7 for Einstein Gravity, vB^{E.H}>vB^{E.G.B}>vB^{3rd Lovelock} . Maybe we can conclude that by adding higher order curvature corrections to Einstein Gravity the butterfly velocity decreases.
Einstein-Weyl spaces and third-order differential equations
Tod, K. P.
2000-08-01
The three-dimensional null-surface formalism of Tanimoto [M. Tanimoto, "On the null surface formalism," Report No. gr-qc/9703003 (1997)] and Forni et al. [Forni et al., "Null surfaces formation in 3D," J. Math Phys. (submitted)] are extended to describe Einstein-Weyl spaces, following Cartan [E. Cartan, "Les espaces généralisées et l'integration de certaines classes d'equations différentielles," C. R. Acad. Sci. 206, 1425-1429 (1938); "La geometria de las ecuaciones diferenciales de tercer order," Rev. Mat. Hispano-Am. 4, 1-31 (1941)]. In the resulting formalism, Einstein-Weyl spaces are obtained from a particular class of third-order differential equations. Some examples of the construction which include some new Einstein-Weyl spaces are given.
Third order nonlinear optical properties of a paratellurite single crystal
Duclère, J.-R.; Hayakawa, T.; Roginskii, E. M.; Smirnov, M. B.; Mirgorodsky, A.; Couderc, V.; Masson, O.; Colas, M.; Noguera, O.; Rodriguez, V.; Thomas, P.
2018-05-01
The (a,b) plane angular dependence of the third-order nonlinear optical susceptibility, χ(3) , of a c-cut paratellurite (α-TeO2) single crystal was quantitatively evaluated here by the Z-scan technique, using a Ti:sapphire femtosecond laser operated at 800 nm. In particular, the mean value Re( ⟨χ(3)⟩a,b )(α-TeO2) of the optical tensor has been extracted from such experiments via a direct comparison with the data collected for a fused silica reference glass plate. A R e (⟨χ(3)⟩(a,b )(α-TeO2)):R e (χ(3))(SiO2 glass) ratio roughly equal to 49.1 is found, and our result compares thus very favourably with the unique experimental value (a ratio of ˜50) reported by Kim et al. [J. Am. Ceram. Soc. 76, 2486 (1993)] for a pure TeO2 glass. In addition, it is shown that the angular dependence of the phase modulation within the (a,b) plane can be fully understood in the light of the strong dextro-rotatory power known for TeO2 materials. Taking into account the optical activity, some analytical model serving to estimate the diagonal and non-diagonal components of the third order nonlinear susceptibility tensor has been thus developed. Finally, Re( χxxxx(3) ) and Re( χxxyy(3) ) values of 95.1 ×10-22 m 2/V2 and 42.0 ×10-22 m2/V2 , respectively, are then deduced for a paratellurite single crystal, considering fused silica as a reference.
Quadratic third-order tensor optimization problem with quadratic constraints
Directory of Open Access Journals (Sweden)
Lixing Yang
2014-05-01
Full Text Available Quadratically constrained quadratic programs (QQPs problems play an important modeling role for many diverse problems. These problems are in general NP hard and numerically intractable. Semidenite programming (SDP relaxations often provide good approximate solutions to these hard problems. For several special cases of QQP, e.g., convex programs and trust region subproblems, SDP relaxation provides the exact optimal value, i.e., there is a zero duality gap. However, this is not true for the general QQP, or even the QQP with two convex constraints, but a nonconvex objective.In this paper, we consider a certain QQP where the variable is neither vector nor matrix but a third-order tensor. This problem can be viewed as a generalization of the ordinary QQP with vector or matrix as it's variant. Under some mild conditions, we rst show that SDP relaxation provides exact optimal solutions for the original problem. Then we focus on two classes of homogeneous quadratic tensor programming problems which have no requirements on the constraints number. For one, we provide an easily implemental polynomial time algorithm to approximately solve the problem and discuss the approximation ratio. For the other, we show there is no gap between the SDP relaxation and itself.
Third-order nonlinear optical properties of ADP crystal
Wang, Mengxia; Wang, Zhengping; Chai, Xiangxu; Sun, Yuxiang; Sui, Tingting; Sun, Xun; Xu, Xinguang
2018-05-01
By using the Z-scan method, we investigated the third-order nonlinear optical (NLO) properties of ADP crystal at different wavelengths (355, 532, and 1064 nm) and different orientations ([001], [100], [110], I and II). The experimental data were fitted by NLO theory, to give out the two photon absorption (TPA) coefficient β 2 and the nonlinear refractive index n 2. When the light source changed from a 40 ps, 1064 nm fundamental laser to a 30 ps, 355 nm third-harmonic-generation (THG) laser, the β 2 value increased about 5 times (0.2 × 10‑2 → 1 × 10‑2 cm GW‑1), and the n 2 value increased about 1.5 times (1.5 × 10‑16 → 2.2 × 10‑16 cm2 W‑1). Among all of the orientations, the [110] sample exhibits the smallest β 2, and the second smallest n 2. It indicates that this orientation and its surroundings will be the preferred directions for high-power laser applications of ADP crystal.
Testing quantum mechanics using third-order correlations
International Nuclear Information System (INIS)
Kinsler, P.
1996-01-01
Semiclassical theories similar to stochastic electrodynamics are widely used in optics. The distinguishing feature of such theories is that the quantum uncertainty is represented by random statistical fluctuations. They can successfully predict some quantum-mechanical phenomena; for example, the squeezing of the quantum uncertainty in the parametric oscillator. However, since such theories are not equivalent to quantum mechanics, they will not always be useful. Complex number representations can be used to exactly model the quantum uncertainty, but care has to be taken that approximations do not reduce the description to a hidden variable one. This paper helps show the limitations of open-quote open-quote semiclassical theories,close-quote close-quote and helps show where a true quantum-mechanical treatment needs to be used. Third-order correlations are a test that provides a clear distinction between quantum and hidden variable theories in a way analogous to that provided by the open-quote open-quote all or nothing close-quote close-quote Greenberger-Horne-Zeilinger test of local hidden variable theories. copyright 1996 The American Physical Society
A covariant Poisson deformation quantization with separation of variables up to the third order
Karabegov, Alexander
2002-01-01
We give a simple formula for the operator C_3 of the standard deformation quantization with separation of variables on a K\\"ahler manifold M. Unlike C_1 and C_2, this operator can not be expressed in terms of the K\\"ahler-Poisson tensor on M. We modify C_3 to obtain a covariant deformation quantization with separation of variables up to the third order which is expressed in terms of the Poisson tensor on M and thus can be defined on an arbitrary complex manifold endowed with a Poisson bivecto...
International Nuclear Information System (INIS)
Hwang, Jai-chan; Noh, Hyerim
2005-01-01
We consider a general relativistic zero-pressure irrotational cosmological medium perturbed to the third order. We assume a flat Friedmann background but include the cosmological constant. We ignore the rotational perturbation which decays in expanding phase. In our previous studies we discovered that, to the second-order perturbation, except for the gravitational wave contributions, the relativistic equations coincide exactly with the previously known Newtonian ones. Since the Newtonian second-order equations are fully nonlinear, any nonvanishing third- and higher-order terms in the relativistic analyses are supposed to be pure relativistic corrections. In this work, we derive such correction terms appearing in the third order. Continuing our success in the second-order perturbations, we take the comoving gauge. We discover that the third-order correction terms are of φ v order higher than the second-order terms where φ v is a gauge-invariant combination related to the three-space curvature perturbation in the comoving gauge; compared with the Newtonian potential, we have δΦ∼(3/5)φ v to the linear order. Therefore, the pure general relativistic effects are of φ v order higher than the Newtonian ones. The corrections terms are independent of the horizon scale and depend only on the linear-order gravitational potential (curvature) perturbation strength. From the temperature anisotropy of cosmic microwave background, we have (δT/T)∼(1/3)δΦ∼(1/5)φ v ∼10 -5 . Therefore, our present result reinforces our previous important practical implication that near the current era one can use the large-scale Newtonian numerical simulation more reliably even as the simulation scale approaches near (and goes beyond) the horizon
Stabilization of third-order bilinear systems using constant controls
Directory of Open Access Journals (Sweden)
A. E. Golubev
2014-01-01
Full Text Available This paper deals with the zero equilibrium stabilization for dynamical systems that have control input singularities. A dynamical system with scalar control input is called nonregular if the coefficient of input becomes null on a subset of the phase space that contains the origin. One of the classes of nonregular dynamical systems is represented by bilinear systems. In case of second-order bilinear systems the necessary and sufficient conditions for the zero equilibrium stabilizability are known in the literature. However, in general case the stabilization problem in the presence of control input singularities has not been solved yet.In this note we solve the problem of the zero equilibrium stabilization for the third-order bilinear dynamical systems given in a canonical form. The solution is found in the class of constant controls. The necessary and sufficient conditions are obtained for the zero equilibrium stabilizability of the bilinear systems in question.The dependence of the zero equilibrium stabilizability on system parameter values is analyzed. The general criteria of stabilizability by means of constant controls are given for the bilinear systems in question. In case when all the system parameters have nonzero values the necessary and sufficient stabilizability conditions are proved. The case when some of the parameters are equal to zero is also considered.Further research can be focused on extending the obtained results to a higher-order case of bilinear and affine dynamical systems. The solution of the considered stabilization problem should also be found not only within constant controls but also in a class of state feedbacks, particularly, in the case when stabilizing constant control does not exist.One of the potential application areas for the obtained theoretical results is automatic control of technical plants like unmanned aerial vehicles and mobile robots.
Dynamics of solitons and quasisolitons of the cubic third-order nonlinear Schrödinger equation
DEFF Research Database (Denmark)
Karpman, V.I.; Juul Rasmussen, J.; Shagalov, A.G.
2001-01-01
The dynamics of soliton and quasisoliton solutions of the cubic third-order nonlinear Schrodinger equation is studied. Regular solitons exist due to a balance between the nonlinear terms and (linear) third-order dispersion; they are not important at small alpha (3) (alpha (3) is the coefficient...... in the third derivative term) and vanish at alpha3 -->0. The most essential, at small alpha (3), is a quasisoliton emitting resonant radiation (resonantly radiating soliton). Its relationship with the other (steady) quasisoliton, called embedded soliton, is studied analytically and also in numerical...
Third-order nonlinear differential operators preserving invariant subspaces of maximal dimension
International Nuclear Information System (INIS)
Qu Gai-Zhu; Zhang Shun-Li; Li Yao-Long
2014-01-01
In this paper, third-order nonlinear differential operators are studied. It is shown that they are quadratic forms when they preserve invariant subspaces of maximal dimension. A complete description of third-order quadratic operators with constant coefficients is obtained. One example is given to derive special solutions for evolution equations with third-order quadratic operators. (general)
Traversable wormholes satisfying the weak energy condition in third-order Lovelock gravity
Zangeneh, Mahdi Kord; Lobo, Francisco S. N.; Dehghani, Mohammad Hossein
2015-12-01
In this paper, we consider third-order Lovelock gravity with a cosmological constant term in an n -dimensional spacetime M4×Kn -4, where Kn -4 is a constant curvature space. We decompose the equations of motion to four and higher dimensional ones and find wormhole solutions by considering a vacuum Kn -4 space. Applying the latter constraint, we determine the second- and third-order Lovelock coefficients and the cosmological constant in terms of specific parameters of the model, such as the size of the extra dimensions. Using the obtained Lovelock coefficients and Λ , we obtain the four-dimensional matter distribution threading the wormhole. Furthermore, by considering the zero tidal force case and a specific equation of state, given by ρ =(γ p -τ )/[ω (1 +γ )], we find the exact solution for the shape function which represents both asymptotically flat and nonflat wormhole solutions. We show explicitly that these wormhole solutions in addition to traversibility satisfy the energy conditions for suitable choices of parameters and that the existence of a limited spherically symmetric traversable wormhole with normal matter in a four-dimensional spacetime implies a negative effective cosmological constant.
Third-order QCD corrections to the charged-current structure function F3
International Nuclear Information System (INIS)
Moch, S.; Vermaseren, J.A.M.; Vogt, A.
2008-12-01
We compute the coefficient function for the charge-averaged W ± -exchange structure function F 3 in deep-inelastic scattering (DIS) to the third order in massless perturbative QCD. Our new three-loop contribution to this quantity forms, at not too small values of the Bjorken variable x, the dominant part of the next-to-next-to-next-to-leading order corrections. It thus facilitates improved determinations of the strong coupling α s and of 1/Q 2 power corrections from scaling violations measured in neutrino-nucleon DIS. The expansion of F 3 in powers of α s is stable at all values of x relevant to measurements at high scales Q 2 . At small x the third-order coefficient function is dominated by diagrams with the colour structure d abc d abc not present at lower orders. At large x the coefficient function for F 3 is identical to that of F 1 up to terms vanishing for x→1. (orig.)
Third-order QCD corrections to the charged-current structure function F{sub 3}
Energy Technology Data Exchange (ETDEWEB)
Moch, S. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Vermaseren, J.A.M. [NIKHEF, Amsterdam (Netherlands); Vogt, A. [Liverpool Univ. (United Kingdom). Dept. of Mathematical Sciences
2008-12-15
We compute the coefficient function for the charge-averaged W{sup {+-}}-exchange structure function F{sub 3} in deep-inelastic scattering (DIS) to the third order in massless perturbative QCD. Our new three-loop contribution to this quantity forms, at not too small values of the Bjorken variable x, the dominant part of the next-to-next-to-next-to-leading order corrections. It thus facilitates improved determinations of the strong coupling {alpha}{sub s} and of 1/Q{sup 2} power corrections from scaling violations measured in neutrino-nucleon DIS. The expansion of F{sub 3} in powers of {alpha}{sub s} is stable at all values of x relevant to measurements at high scales Q{sup 2}. At small x the third-order coefficient function is dominated by diagrams with the colour structure d{sup abc}d{sub abc} not present at lower orders. At large x the coefficient function for F{sub 3} is identical to that of F{sub 1} up to terms vanishing for x{yields}1. (orig.)
Comparison of third-order plasma wave echoes with ballistic second-order plasma wave echoes
International Nuclear Information System (INIS)
Leppert, H.D.; Schuelter, H.; Wiesemann, K.
1982-01-01
The apparent dispersion of third-order plasma wave echoes observed in a high frequency plasma is compared with that of simultaneously observed ballistic second-order echoes. Amplitude and wavelength of third-order echoes are found to be always smaller than those of second-order echoes, however, the dispersion curves of both types of echoes are very similar. These observations are in qualitative agreement with calculations of special ballistic third-order echoes. The ballistic nature of the observed third-order echoes may, therefore, be concluded from these measurements. (author)
Spherically Symmetric Gravitational Collapse of a Dust Cloud in Third-Order Lovelock Gravity
Zhou, Kang; Yang, Zhan-Ying; Zou, De-Cheng; Yue, Rui-Hong
We investigate the spherically symmetric gravitational collapse of an incoherent dust cloud by considering a LTB-type spacetime in third-order Lovelock Gravity without cosmological constant, and give three families of LTB-like solutions which separately corresponding to hyperbolic, parabolic and elliptic. Notice that the contribution of high-order curvature corrections have a profound influence on the nature of the singularity, and the global structure of spacetime changes drastically from the analogous general relativistic case. Interestingly, the presence of high order Lovelock terms leads to the formation of massive, naked and timelike singularities in the 7D spacetime, which is disallowed in general relativity. Moveover, we point out that the naked singularities in the 7D case may be gravitational weak therefore may not be a serious threat to the cosmic censorship hypothesis, while the naked singularities in the D ≥ 8 inhomogeneous collapse violate the cosmic censorship hypothesis seriously.
A fluctuation method to calculate the third order elastic constants in crystalline solids
Energy Technology Data Exchange (ETDEWEB)
Chen, Zimu [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Qu, Jianmin, E-mail: j-qu@northwestern.edu [Department of Civil and Environmental Engineering, Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208 (United States)
2015-05-28
This paper derives exact expressions of the isothermal third order elastic constants (TOE) in crystalline solids in terms of the kinetic and potential energies of the system. These expressions reveal that the TOE constants consist of a Born component and a relaxation component. The Born component is simply the third derivative of the system's potential energy with respect to the deformation, while the relaxation component is related to the non-uniform rearrangements of the atoms when the system is subject to a macroscopic deformation. Further, based on the general expressions derived here, a direct (fluctuation) method of computing the isothermal TOE constants is developed. Numerical examples of using this fluctuation method are given to compute the TOE constants of single crystal iron.
SIMPLE MODELS OF THREE COUPLED PT -SYMMETRIC WAVE GUIDES ALLOWING FOR THIRD-ORDER EXCEPTIONAL POINTS
Directory of Open Access Journals (Sweden)
Jan Schnabel
2017-12-01
Full Text Available We study theoretical models of three coupled wave guides with a PT-symmetric distribution of gain and loss. A realistic matrix model is developed in terms of a three-mode expansion. By comparing with a previously postulated matrix model it is shown how parameter ranges with good prospects of finding a third-order exceptional point (EP3 in an experimentally feasible arrangement of semiconductors can be determined. In addition it is demonstrated that continuous distributions of exceptional points, which render the discovery of the EP3 difficult, are not only a feature of extended wave guides but appear also in an idealised model of infinitely thin guides shaped by delta functions.
Photo-physics of third-order nonlinear optical processes in organic dyes
International Nuclear Information System (INIS)
Delysse, Stephane
1997-01-01
We study some aspects of the nonlinear picosecond photo-physics in organic dyes using Kerr ellipsometry. The aim is to establish link between the photo-physics and nonlinear optics in these compounds. First, we study coherent processes directly linked to the third-order susceptibility. Thus, we measure two-photon absorption spectra of large internal charge transfer dyes. We take into account all coupling between three electronic states which can interfere to explain the particular response of some stilbene dyes. On the second hand, we expose a more photophysical approach to determine the S 1 → S n transition energies and moments using the measurement of excited state absorption cross sections. These results allow the prediction of the susceptibilities relevant to alternative nonlinear optical methods. Nevertheless, the stationary approach hides the complex relaxation processes which can take place in organic dyes. As an illustration, we study the formation and disappearance of a TICT (Twisted intramolecular charge transfer) in a pyrylium salt in solvents of increasing viscosity. (author) [fr
Orientational and electronic contributions to the third-order susceptibilities of cryogenic liquids
International Nuclear Information System (INIS)
Kildal, H.; Brueck, S.R.J.
1980-01-01
Alternating current Kerr effect and third-harmonic generation (THG) are reported for the cryogenic liquids CO, O 2 , N 2 , and Ar pumped by CO 2 TEA laser radiation. The THG experiments measure the hyperpolarizability, while the Kerr effect measurements probe the total nonresonant third-order susceptibility chi/sup( 3 ), arising from both molecular orientation and electronic hyperpolarizability. The THG process in liquid CO is dominated by a vibrational two-photon resonant contribution for the CO 2 R(6) pump line at 9.35 μm. By studying the interference between the resonant and nonresonant contributions in liquid CO--O 2 mixtures the hyperpolarizability of liquid O 2 has been determined relative to the two-photon resonant chi/sup( 3 ) of liquid CO. These measurements give the first experimental confirmation for liquid media that the two-photon resonance contribution to polarized scattering consists of both narrow and broad linewidth components associated with, respectively, the isotropic and anisotropic Raman polarizabilities
Third-order particle-hole ring diagrams with contact-interactions and one-pion exchange
Energy Technology Data Exchange (ETDEWEB)
Kaiser, N. [Technische Universitaet Muenchen, Physik-Department T39, Garching (Germany)
2017-05-15
The third-order particle-hole ring diagrams are evaluated for a NN-contact interaction of the Skyrme type. The pertinent four-loop coefficients in the energy per particle anti E(k{sub f}) ∝ k{sub f}{sup 5+2n} are reduced to double integrals over cubic expressions in Euclidean polarization functions. Dimensional regularization of divergent integrals is performed by subtracting power divergences and the validity of this method is checked against the known analytical results at second order. The complete O(p{sup 2}) NN-contact interaction is obtained by adding two tensor terms and their third-order ring contributions are also calculated in detail. The third-order ring energy arising from long-range 1π-exchange is computed and it is found that direct and exchange contributions are all attractive. The very large size of the three-ring energy due to point-like 1π-exchange, anti E(k{sub f0}) ≅ -92 MeV at saturation density, is however in no way representative for that of realistic chiral NN-potentials. Moreover, the third-order (particle-particle and hole-hole) ladder diagrams are evaluated with the full O(p{sup 2}) contact interaction, and the simplest three-ring contributions to the isospin-asymmetry energy A(k{sub f}) ∝ k{sub f}{sup 5} are studied. (orig.)
Transfer Failure and Proactive Interference in Short-Term Memory
Ellis, John A.
1977-01-01
Two experiments tested the hypothesis that proactive interference over a series of Brown-Peterson trials results from a combination of the subject's failure to transfer information to a permanent memory state and failure to retrieve information from permanent memory. (Editor)
Periodic solutions of certain third order nonlinear differential systems with delay
International Nuclear Information System (INIS)
Tejumola, H.O.; Afuwape, A.U.
1990-12-01
This paper investigates the existence of 2π-periodic solutions of systems of third-order nonlinear differential equations, with delay, under varied assumptions. The results obtained extend earlier works of Tejumola and generalize to third order systems those of Conti, Iannacci and Nkashama as well as DePascale and Iannacci and Iannacci and Nkashama. 16 refs
Yang, Lin; Guo, Peng; Yang, Aiying; Qiao, Yaojun
2018-02-01
In this paper, we propose a blind third-order dispersion estimation method based on fractional Fourier transformation (FrFT) in optical fiber communication system. By measuring the chromatic dispersion (CD) at different wavelengths, this method can estimation dispersion slope and further calculate the third-order dispersion. The simulation results demonstrate that the estimation error is less than 2 % in 28GBaud dual polarization quadrature phase-shift keying (DP-QPSK) and 28GBaud dual polarization 16 quadrature amplitude modulation (DP-16QAM) system. Through simulations, the proposed third-order dispersion estimation method is shown to be robust against nonlinear and amplified spontaneous emission (ASE) noise. In addition, to reduce the computational complexity, searching step with coarse and fine granularity is chosen to search optimal order of FrFT. The third-order dispersion estimation method based on FrFT can be used to monitor the third-order dispersion in optical fiber system.
Resolving semantic and proactive interference in memory over the short-term.
Atkins, Alexandra S; Berman, Marc G; Reuter-Lorenz, Patricia A; Lewis, Richard L; Jonides, John
2011-07-01
Interference is a major source of short-term errors of memory. The present investigation explores the relationship between two important forms of interference: proactive interference (PI), induced by the need to reject recently studied items no longer relevant to task performance, and semantic interference (SI), induced by the need to reject lures sharing a meaningful relationship with current memoranda. We explore the possibility that shared cognitive control processes are recruited to resolve both forms of interference. In Experiment 1, we find that the requirement to engage in articulatory suppression during the retention interval of tasks that induce either PI or SI increases both forms of interference similarly and selectively. In Experiment 2, we develop a task to examine PI and SI within the same experimental context. The results show interactive effects between factors that lead to the two forms of interference. Taken together, these findings support contextual-cuing models of short-term remembering (Nairne, Annual Review of Psychology, 53, 53-81 2002), where the context in which retrieval occurs can influence susceptibility to interference. Lastly, we discuss several theoretical hypotheses concerning the cognitive control processes that are recruited to resolve SI and PI in short-term remembering.
Correlation effects of third-order perturbation in the extended Hubbard model
International Nuclear Information System (INIS)
Wei, G.Z.; Nie, H.Q.; Li, L.; Zhang, K.Y.
1989-01-01
Using the local approach, a third-order perturbation calculation has been performed to investigate the effects of intra-atomic electron correlation and electron and spin correlation between nearest neighbour sites in the extended Hubbard model. It was found that significant correction of the third order over the second order results and, in comparison with the results of the third-order perturbation where only the intra-atomic electron correlation is included, the influence of the electron and spin correlation between nearest neighbour sites on the correlation energy is non-negligible. 17 refs., 3 figs
Proactive Interference and Directed Forgetting in Short-Term Motor Memory
Burwitz, Leslie
1974-01-01
The present study was designed to test the effect of instructions to forget prior motor learning and the results were relevant to the understanding of short-term motor memory (STMM) proactive interference (PI). (Author/RK)
Mordik, S N
2002-01-01
The third-order transfer matrices are calculated for an electrostatic toroidal sector condenser using a rigorously conserved matrix method that implies the conservation of the beam phase volume at each step in the calculations. The transfer matrices (matrizants) obtained, include the fringing-field effect due to the stray fields. In the case of a rectangular distribution of the field components along the optical axis, the analytical expressions for all aberration coefficients, including the dispersion ones, are derived accurate to the third-order terms. In simulations of real fields with the stray field width other than zero, a smooth distribution of the field components is used for which similar aberration coefficients were calculated by means of the conserved numerical method . It has been found that for a smooth model, as the stray field width tends to zero, the aberration coefficients approach the corresponding aberration values in the rectangular model.
International Nuclear Information System (INIS)
Davies, J.; Vogt, A.
2016-06-01
We have calculated the coefficient functions for the structure functions F_2, F_L and F_3 in ν- anti ν charged-current deep-inelastic scattering (DIS) at the third order in the strong coupling α_s, thus completing the description of unpolarized inclusive W"±-exchange DIS to this order of massless perturbative QCD. In this brief note, our new results are presented in terms of compact approximate expressions that are sufficiently accurate for phenomenological analyses. For the benefit of such analyses we also collect, in a unified notation, the corresponding lower-order contributions and the flavour non-singlet coefficient functions for ν+ anti ν charged-current DIS. The behaviour of all six third-order coefficient functions at small Bjorken-x is briefly discussed.
International Nuclear Information System (INIS)
Mordik, S.N.; Ponomarev, A.G.
2002-01-01
The third-order transfer matrices are calculated for an electrostatic toroidal sector condenser using a rigorously conserved matrix method that implies the conservation of the beam phase volume at each step in the calculations. The transfer matrices (matrizants) obtained, include the fringing-field effect due to the stray fields. In the case of a rectangular distribution of the field components along the optical axis, the analytical expressions for all aberration coefficients, including the dispersion ones, are derived accurate to the third-order terms. In simulations of real fields with the stray field width other than zero, a smooth distribution of the field components is used for which similar aberration coefficients were calculated by means of the conserved numerical method . It has been found that for a smooth model, as the stray field width tends to zero, the aberration coefficients approach the corresponding aberration values in the rectangular model
Free vibration analysis of beams by using a third-order shear ...
Indian Academy of Sciences (India)
Free vibrations of beams; the third-order shear deformation theory; ... Thus, a shear correction factor is required to compensate for the error because of ...... Wang C M, Kitipornchai S 2003 Vibration of Timoshenko beams with internal hinge.
Two new solutions to the third-order symplectic integration method
International Nuclear Information System (INIS)
Iwatsu, Reima
2009-01-01
Two new solutions are obtained for the symplecticity conditions of explicit third-order partitioned Runge-Kutta time integration method. One of them has larger stability limit and better dispersion property than the Ruth's method.
ON THE BOUNDEDNESS AND THE STABILITY OF SOLUTION TO THIRD ORDER NON-LINEAR DIFFERENTIAL EQUATIONS
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
In this paper we investigate the global asymptotic stability,boundedness as well as the ultimate boundedness of solutions to a general third order nonlinear differential equation,using complete Lyapunov function.
Third-order ordinary differential equations Y”' = f(x, y, y'', y′”) with ...
African Journals Online (AJOL)
dimensional symmetry algebra. Mathematics Subject Classication (2010): 34A05, 34A25, 53A55, 76M60. Key words: Linearization, third order ODEs, point transformation, contact transformation, Lie symmetries, relative differential invariants.
Z-scan: A simple technique for determination of third-order optical nonlinearity
Energy Technology Data Exchange (ETDEWEB)
Singh, Vijender, E-mail: chahal-gju@rediffmail.com [Department of Applied Science, N.C. College of Engineering, Israna, Panipat-132107, Haryana (India); Aghamkar, Praveen, E-mail: p-aghamkar@yahoo.co.in [Department of Physics, Chaudhary Devi Lal University, Sirsa-125055, Haryana (India)
2015-08-28
Z-scan is a simple experimental technique to measure intensity dependent nonlinear susceptibilities of third-order nonlinear optical materials. This technique is used to measure the sign and magnitude of both real and imaginary part of the third order nonlinear susceptibility (χ{sup (3)}) of nonlinear optical materials. In this paper, we investigate third-order nonlinear optical properties of Ag-polymer composite film by using single beam z-scan technique with Q-switched, frequency doubled Nd: YAG laser (λ=532 nm) at 5 ns pulse. The values of nonlinear absorption coefficient (β), nonlinear refractive index (n{sub 2}) and third-order nonlinear optical susceptibility (χ{sup (3)}) of permethylazine were found to be 9.64 × 10{sup −7} cm/W, 8.55 × 10{sup −12} cm{sup 2}/W and 5.48 × 10{sup −10} esu, respectively.
Time manages interference in visual short-term memory.
Smith, Amy V; McKeown, Denis; Bunce, David
2017-09-01
Emerging evidence suggests that age-related declines in memory may reflect a failure in pattern separation, a process that is believed to reduce the encoding overlap between similar stimulus representations during memory encoding. Indeed, behavioural pattern separation may be indexed by a visual continuous recognition task in which items are presented in sequence and observers report for each whether it is novel, previously viewed (old), or whether it shares features with a previously viewed item (similar). In comparison to young adults, older adults show a decreased pattern separation when the number of items between "old" and "similar" items is increased. Yet the mechanisms of forgetting underpinning this type of recognition task are yet to be explored in a cognitively homogenous group, with careful control over the parameters of the task, including elapsing time (a critical variable in models of forgetting). By extending the inter-item intervals, number of intervening items and overall decay interval, we observed in a young adult sample (N = 35, M age = 19.56 years) that the critical factor governing performance was inter-item interval. We argue that tasks using behavioural continuous recognition to index pattern separation in immediate memory will benefit from generous inter-item spacing, offering protection from inter-item interference.
Neipert, Christine; Space, Brian
2006-12-14
Sum vibrational frequency spectroscopy, a second order optical process, is interface specific in the dipole approximation. At charged interfaces, there exists a static field, and as a direct consequence, the experimentally detected signal is a combination of enhanced second and static field induced third order contributions. There is significant evidence in the literature of the importance/relative magnitude of this third order contribution, but no previous molecularly detailed approach existed to separately calculate the second and third order contributions. Thus, for the first time, a molecularly detailed time correlation function theory is derived here that allows for the second and third order contributions to sum frequency vibrational spectra to be individually determined. Further, a practical, molecular dynamics based, implementation procedure for the derived correlation functions that describe the third order phenomenon is also presented. This approach includes a novel generalization of point atomic polarizability models to calculate the hyperpolarizability of a molecular system. The full system hyperpolarizability appears in the time correlation functions responsible for third order contributions in the presence of a static field.
Third-order elastic moduli for alkali-halide crystals possessing the sodium chloride structure
International Nuclear Information System (INIS)
Ray, U.
2010-01-01
The values of third-order elastic moduli for alkali halides, having NaCl-type crystal structure are calculated according to the Born-Mayer potential model, considering the repulsive interactions up to the second nearest neighbours and calculating the values of the potential parameters for each crystal, independently, from the compressibility data. This work presents the first published account of the calculation of the third-order elastic moduli taking the actual value of the potential parameter unlike the earlier works. Third-order elastic constants have been computed for alkali halides at 0 and 300 K. The results of the third-order elastic constants are compared with the available experimental and theoretical data. Very good agreement between experimental and theoretical third-order elastic constant data (except C 123 ) is found. We have also computed the values of the pressure derivatives of second-order elastic constants and Anderson-Grueneisen parameter for alkali halides, which agree reasonably well with the experimental values, indicating the satisfactory nature of our computed data for third-order elastic constants.
Directory of Open Access Journals (Sweden)
Qicheng Meng
2016-04-01
Full Text Available A third-order KdV solution to the internal solitary wave is derived by a new method based on the weakly nonlinear assumptions in a rigid-lid two-layer system. The solution corrects an error by Mirie and Su (1984. A two-dimensional numerical wave tank has been established with the help of the open source CFD library OpenFOAM and the third-party software waves2Foam. Various analytical solutions, including the first-order to third-order KdV solutions, the eKdV solution and the MCC solution, have been used to initialise the flow fields in the CFD simulations of internal solitary waves. Two groups including 11 numerical cases have been carried out. In the same group, the initial wave amplitudes are the same but the implemented analytical solutions are different. The simulated wave profiles at different moments have been presented. The relative errors in terms of the wave amplitude between the last time step and the initial input have been analysed quantitatively. It is found that the third-order KdV solution results in the most stable internal solitary wave in the numerical wave tank for both small-amplitude and finite-amplitude cases. The finding is significant for the further simulations involving internal solitary waves.
Long-term effects of interference on short-term memory performance in the rat.
Missaire, Mégane; Fraize, Nicolas; Joseph, Mickaël Antoine; Hamieh, Al Mahdy; Parmentier, Régis; Marighetto, Aline; Salin, Paul Antoine; Malleret, Gaël
2017-01-01
A distinction has always been made between long-term and short-term memory (also now called working memory, WM). The obvious difference between these two kinds of memory concerns the duration of information storage: information is supposedly transiently stored in WM while it is considered durably consolidated into long-term memory. It is well acknowledged that the content of WM is erased and reset after a short time, to prevent irrelevant information from proactively interfering with newly stored information. In the present study, we used typical WM radial maze tasks to question the brief lifespan of spatial WM content in rodents. Groups of rats were submitted to one of two different WM tasks in a radial maze: a WM task involving the repetitive presentation of a same pair of arms expected to induce a high level of proactive interference (PI) (HIWM task), or a task using a different pair in each trial expected to induce a low level of PI (LIWM task). Performance was effectively lower in the HIWM group than in LIWM in the final trial of each training session, indicative of a "within-session/short-term" PI effect. However, we also observed a different "between-session/long-term" PI effect between the two groups: while performance of LIWM trained rats remained stable over days, the performance of HIWM rats dropped after 10 days of training, and this impairment was visible from the very first trial of the day, hence not attributable to within-session PI. We also showed that a 24 hour-gap across training sessions known to allow consolidation processes to unfold, was a necessary and sufficient condition for the long-term PI effect to occur. These findings suggest that in the HIWM task, WM content was not entirely reset between training sessions and that, in specific conditions, WM content can outlast its purpose by being stored more permanently, generating a long-term deleterious effect of PI. The alternative explanation is that WM content could be transferred and stored
Long-term effects of interference on short-term memory performance in the rat.
Directory of Open Access Journals (Sweden)
Mégane Missaire
Full Text Available A distinction has always been made between long-term and short-term memory (also now called working memory, WM. The obvious difference between these two kinds of memory concerns the duration of information storage: information is supposedly transiently stored in WM while it is considered durably consolidated into long-term memory. It is well acknowledged that the content of WM is erased and reset after a short time, to prevent irrelevant information from proactively interfering with newly stored information. In the present study, we used typical WM radial maze tasks to question the brief lifespan of spatial WM content in rodents. Groups of rats were submitted to one of two different WM tasks in a radial maze: a WM task involving the repetitive presentation of a same pair of arms expected to induce a high level of proactive interference (PI (HIWM task, or a task using a different pair in each trial expected to induce a low level of PI (LIWM task. Performance was effectively lower in the HIWM group than in LIWM in the final trial of each training session, indicative of a "within-session/short-term" PI effect. However, we also observed a different "between-session/long-term" PI effect between the two groups: while performance of LIWM trained rats remained stable over days, the performance of HIWM rats dropped after 10 days of training, and this impairment was visible from the very first trial of the day, hence not attributable to within-session PI. We also showed that a 24 hour-gap across training sessions known to allow consolidation processes to unfold, was a necessary and sufficient condition for the long-term PI effect to occur. These findings suggest that in the HIWM task, WM content was not entirely reset between training sessions and that, in specific conditions, WM content can outlast its purpose by being stored more permanently, generating a long-term deleterious effect of PI. The alternative explanation is that WM content could be
Validity testing of third-order nonlinear models for synchronous generators
Energy Technology Data Exchange (ETDEWEB)
Arjona, M.A. [Division de Estudios de Posgrado e Investigacion, Instituto Tecnologico de La Laguna Torreon, Coah. (Mexico); Escarela-Perez, R. [Universidad Autonoma Metropolitana - Azcapotzalco, Departamento de Energia, Av. San Pablo 180, Col. Reynosa, C.P. 02200 (Mexico); Espinosa-Perez, G. [Division de Estudios Posgrado de la Facultad de Ingenieria Universidad Nacional Autonoma de Mexico (Mexico); Alvarez-Ramirez, J. [Universidad Autonoma Metropolitana -Iztapalapa, Division de Ciencias Basicas e Ingenieria (Mexico)
2009-06-15
Third-order nonlinear models are commonly used in control theory for the analysis of the stability of both open-loop and closed-loop synchronous machines. However, the ability of these models to describe the electrical machine dynamics has not been tested experimentally. This work focuses on this issue by addressing the parameters identification problem for third-order models for synchronous generators. For a third-order model describing the dynamics of power angle {delta}, rotor speed {omega} and quadrature axis transient EMF E{sub q}{sup '}, it is shown that the parameters cannot be identified because of the effects of the unknown initial condition of E{sub q}{sup '}. To avoid this situation, a model that incorporates the measured electrical power dynamics is considered, showing that state measurements guarantee the identification of the model parameters. Data obtained from a 7 kVA lab-scale synchronous generator and from a 150 MVA finite-element simulation were used to show that, at least for the worked examples, the estimated parameters display only moderate variations over the operating region. This suggests that third-order models can suffice to describe the main dynamical features of synchronous generators, and that third-order models can be used to design and tune power system stabilizers and voltage regulators. (author)
Algebraic Properties of First Integrals for Scalar Linear Third-Order ODEs of Maximal Symmetry
Directory of Open Access Journals (Sweden)
K. S. Mahomed
2013-01-01
Full Text Available By use of the Lie symmetry group methods we analyze the relationship between the first integrals of the simplest linear third-order ordinary differential equations (ODEs and their point symmetries. It is well known that there are three classes of linear third-order ODEs for maximal cases of point symmetries which are 4, 5, and 7. The simplest scalar linear third-order equation has seven-point symmetries. We obtain the classifying relation between the symmetry and the first integral for the simplest equation. It is shown that the maximal Lie algebra of a first integral for the simplest equation y′′′=0 is unique and four-dimensional. Moreover, we show that the Lie algebra of the simplest linear third-order equation is generated by the symmetries of the two basic integrals. We also obtain counting theorems of the symmetry properties of the first integrals for such linear third-order ODEs. Furthermore, we provide insights into the manner in which one can generate the full Lie algebra of higher-order ODEs of maximal symmetry from two of their basic integrals.
Directory of Open Access Journals (Sweden)
K. S. Mahomed
2013-01-01
Full Text Available The relationship between first integrals of submaximal linearizable third-order ordinary differential equations (ODEs and their symmetries is investigated. We obtain the classifying relations between the symmetries and the first integral for submaximal cases of linear third-order ODEs. It is known that the maximum Lie algebra of the first integral is achieved for the simplest equation and is four-dimensional. We show that for the other two classes they are not unique. We also obtain counting theorems of the symmetry properties of the first integrals for these classes of linear third-order ODEs. For the 5 symmetry class of linear third-order ODEs, the first integrals can have 0, 1, 2, and 3 symmetries, and for the 4 symmetry class of linear third-order ODEs, they are 0, 1, and 2 symmetries, respectively. In the case of submaximal linear higher-order ODEs, we show that their full Lie algebras can be generated by the subalgebras of certain basic integrals.
International Nuclear Information System (INIS)
Matsyuk, R.Ya.
1985-01-01
The problem on the existence of the invariant third-order Euler-Poisson equations in the pseudo-Euclidean space is investigated. The locally variational problem is determined by the Lagrangian density over the space of the second-order jets. The one - parameter family of the invariant third-order Euler-Poisson equations is groved to be the only one in the three-dimensional pseudo-Euclidean space. No invariant third-order Euler-Poisson equations exist in the four-dimensional pseudo-Euclidean space. It is shown that the Mathisson equation and the equation of geodesic circles in particular cases may be considered in the context of the Ostrogradiskij mechanics and the Kavaguchi geometry
Third-order nonlinear optical properties of thin sputtered gold films
Xenogiannopoulou, E.; Aloukos, P.; Couris, S.; Kaminska, E.; Piotrowska, A.; Dynowska, E.
2007-07-01
Au films of thickness ranging between 5 and 52 nm were prepared by sputtering on quartz substrates and their third-order nonlinear optical response was investigated by Optical Kerr effect (OKE) and Z-scan techniques using 532 nm, 35 ps laser pulses. All prepared films were characterized by XRD, AFM and UV-VIS-NIR spectrophotometry while their third-order susceptibility χ(3) was measured and found to be of the order of 10 -9 esu. The real and imaginary parts of the third-order susceptibility were found in very good agreement with experimental results and theoretical predictions reported by Smith et al. [D.D. Smith, Y. Yoon, R.W. Boyd, Y.K. Cambell, L.A. Baker, R.M. Crooks, M. George, J. Appl. Phys. 86 (1999) 6200].
Surface plasmon enhanced third-order optical nonlinearity of Ag nanocomposite film
Energy Technology Data Exchange (ETDEWEB)
Singh, Vijender [Department of Applied Science, N.C. College of Engineering, Israna, Panipat 132107, Haryana (India); Aghamkar, Praveen, E-mail: p-aghamkar@yahoo.in [Department of Physics, Chaudhary Devi Lal University, Sirsa 125055, Haryana (India)
2014-03-17
We obtain a large third-order optical nonlinearity (χ{sup (3)} ≈ 10{sup −10}esu) of silver nanoparticles dispersed in polyvinyl alcohol/tetraethyl orthosilicate matrix using single beam z-scan technique at 532 nm by Q-switched Nd:YAG laser. We have shown that mechanisms responsible for third-order optical nonlinearity of Ag nanocomposite film are reverse saturable absorption (RSA) and self-defocusing in the purlieu of surface plasmon resonance (SPR). Optical band-gap and width of SPR band of Ag nanocomposite film decrease with increasing silver concentration, which leads to enhancement of local electric field and hence third-order optical nonlinearity. Optical limiting, due to RSA has also been demonstrated at 532 nm.
Surface plasmon enhanced third-order optical nonlinearity of Ag nanocomposite film
International Nuclear Information System (INIS)
Singh, Vijender; Aghamkar, Praveen
2014-01-01
We obtain a large third-order optical nonlinearity (χ (3) ≈ 10 −10 esu) of silver nanoparticles dispersed in polyvinyl alcohol/tetraethyl orthosilicate matrix using single beam z-scan technique at 532 nm by Q-switched Nd:YAG laser. We have shown that mechanisms responsible for third-order optical nonlinearity of Ag nanocomposite film are reverse saturable absorption (RSA) and self-defocusing in the purlieu of surface plasmon resonance (SPR). Optical band-gap and width of SPR band of Ag nanocomposite film decrease with increasing silver concentration, which leads to enhancement of local electric field and hence third-order optical nonlinearity. Optical limiting, due to RSA has also been demonstrated at 532 nm
Evaluation of third order nonlinear optical parameters of CdS/PVA nanocomposite
International Nuclear Information System (INIS)
Sharma, Mamta; Tripathi, S. K.
2015-01-01
CdS nanoparticles dispersed in PVA are prepared by Chemical method at room temperature. The nonlinear optical parameters such as nonlinear absorption (β), nonlinear refractive index (n 2 ) and nonlinear susceptibility (χ 3 ) are calculated for this sample by using Z-scan technique. CdS/PVA samples show the two photon absorption mechanism. The third order nonlinear susceptibility is calculated from n 2 and β and is found to be of the order of 10 −7 – 10 −8 m 2 /V 2 . The larger value of third order nonlinear susceptibility is due to dielectric and quantum confinement effect
The third order nonlinear susceptibility of InAs at infrared region
International Nuclear Information System (INIS)
Musayev, M.A.
2008-01-01
Nonlinear susceptibilities of the third order and coefficient of nonlinear absorption in InAs n-type with a different degree of a doping have been measured. The values of the third order nonlinear susceptibilities have derived from these measurements essentially exceed the values calculated on the basis of model featuring nonlinear susceptibility of electrons, being in conduction-band nonparabolicity. It has been shown that the observable discrepancy has been eliminated, if in calculation a dissipation of energy of electrons has been considered. Growth of efficiency at four-wave mixingin narrow-gap semiconductors has been restricted to nonlinear absorption of interacting waves
Mixed convection peristaltic flow of third order nanofluid with an induced magnetic field.
Noreen, Saima
2013-01-01
This research is concerned with the peristaltic flow of third order nanofluid in an asymmetric channel. The governing equations of third order nanofluid are modelled in wave frame of reference. Effect of induced magnetic field is considered. Long wavelength and low Reynolds number situation is tackled. Numerical solutions of the governing problem are computed and analyzed. The effects of Brownian motion and thermophoretic diffusion of nano particles are particularly emphasized. Physical quantities such as velocity, pressure rise, temperature, induced magnetic field and concentration distributions are discussed.
Alkali-Responsive Absorption Spectra and Third-Order Optical Nonlinearities of Imino Squaramides
International Nuclear Information System (INIS)
Li Zhong-Yu; Xu Song; Zhou Xin-Yu; Zhang Fu-Shi
2012-01-01
Third-order optical nonlinearities and dynamic responses of two imino squaramides under neutral and base conditions were studied using the femtosecond degenerate four-wave mixing technique at 800 nm. Ultrafast optical responses have been observed and the magnitude of the second-order hyperpolarizabilities of the squaramides has been measured to be as large as 10 −31 esu. The absorption spectra, color of solution, and third-order optical nonlinearities of two imino squaramides change with the addition of sodium hydroxide. The γ value under the base condition for each dye is approximately 1.25 times larger than that under neutral conditions. (fundamental areas of phenomenology(including applications))
Mixed convection peristaltic flow of third order nanofluid with an induced magnetic field.
Directory of Open Access Journals (Sweden)
Saima Noreen
Full Text Available This research is concerned with the peristaltic flow of third order nanofluid in an asymmetric channel. The governing equations of third order nanofluid are modelled in wave frame of reference. Effect of induced magnetic field is considered. Long wavelength and low Reynolds number situation is tackled. Numerical solutions of the governing problem are computed and analyzed. The effects of Brownian motion and thermophoretic diffusion of nano particles are particularly emphasized. Physical quantities such as velocity, pressure rise, temperature, induced magnetic field and concentration distributions are discussed.
Directory of Open Access Journals (Sweden)
Gai Gongqi
2011-01-01
Full Text Available Abstract This article studies the boundary value problems for the third-order nonlinear singular difference equations Δ 3 u ( i - 2 + λ a ( i f ( i , u ( i = 0 , i ∈ [ 2 , T + 2 ] , satisfying five kinds of different boundary value conditions. This article shows the existence of positive solutions for positone and semi-positone type. The nonlinear term may be singular. Two examples are also given to illustrate the main results. The arguments are based upon fixed point theorems in a cone. MSC [2008]: 34B15; 39A10.
An algorithm for solving initial value problems of third order ordinary ...
African Journals Online (AJOL)
Abstract. We propose an implicit multi-step method for the solution of initial value problems (IVPs) of third order ordinary differential equations (ODE) which does not require reducing the ODE to first order before solving. The development of the method is based on collocation of the differential system and interpolation of the ...
Multi-octave analog photonic link with improved second- and third-order SFDRs
Tan, Qinggui; Gao, Yongsheng; Fan, Yangyu; He, You
2018-03-01
The second- and third-order spurious free dynamic ranges (SFDRs) are two key performance indicators for a multi-octave analogy photonic link (APL). The linearization methods for either second- or third-order intermodulation distortion (IMD2 or IMD3) have been intensively studied, but the simultaneous suppression for the both were merely reported. In this paper, we propose an APL with improved second- and third-order SFDRs for multi-octave applications based on two parallel DPMZM-based sub-APLs. The IMD3 in each sub-APL is suppressed by properly biasing the DPMZM, and the IMD2 is suppressed by balanced detecting the two sub-APLs. The experiment demonstrates significant suppression ratios for both the IMD2 and IMD3 after linearization in the proposed link, and the measured second- and third-order SFDRs with the operating frequency from 6 to 40 GHz are above 91 dB ṡHz 1 / 2 and 116 dB ṡHz 2 / 3, respectively.
A Three Step Explicit Method for Direct Solution of Third Order ...
African Journals Online (AJOL)
This study produces a three step discrete Linear Multistep Method for Direct solution of third order initial value problems of ordinary differential equations of the form y'''= f(x,y,y',y''). Taylor series expansion technique was adopted in the development of the method. The differential system from the basis polynomial function to ...
Breakdown of the single-exchange approximation in third-order symmetry-adapted perturbation theory.
Lao, Ka Un; Herbert, John M
2012-03-22
We report third-order symmetry-adapted perturbation theory (SAPT) calculations for several dimers whose intermolecular interactions are dominated by induction. We demonstrate that the single-exchange approximation (SEA) employed to derive the third-order exchange-induction correction (E(exch-ind)((30))) fails to quench the attractive nature of the third-order induction (E(ind)((30))), leading to one-dimensional potential curves that become attractive rather than repulsive at short intermolecular separations. A scaling equation for (E(exch-ind)((30))), based on an exact formula for the first-order exchange correction, is introduced to approximate exchange effects beyond the SEA, and qualitatively correct potential energy curves that include third-order induction are thereby obtained. For induction-dominated systems, our results indicate that a "hybrid" SAPT approach, in which a dimer Hartree-Fock calculation is performed in order to obtain a correction for higher-order induction, is necessary not only to obtain quantitative binding energies but also to obtain qualitatively correct potential energy surfaces. These results underscore the need to develop higher-order exchange-induction formulas that go beyond the SEA. © 2012 American Chemical Society
Directory of Open Access Journals (Sweden)
Araz R. Aliev
2013-10-01
Full Text Available We study a third-order operator-differential equation on the semi-axis with a discontinuous coefficient and boundary conditions which include an abstract linear operator. Sufficient conditions for the well-posed and unique solvability are found by means of properties of the operator coefficients in a Sobolev-type space.
Khataybeh, S. N.; Hashim, I.
2018-04-01
In this paper, we propose for the first time a method based on Bernstein polynomials for solving directly a class of third-order ordinary differential equations (ODEs). This method gives a numerical solution by converting the equation into a system of algebraic equations which is solved directly. Some numerical examples are given to show the applicability of the method.
Energy Technology Data Exchange (ETDEWEB)
Divya Bharathi, M.; Ahila, G.; Mohana, J. [Department of Physics, Presidency College, Chennai 600005 (India); Chakkaravarthi, G. [Department of Physics, CPCL Polytechnic College, Chennai 600068 (India); Anbalagan, G., E-mail: anbu24663@yahoo.co.in [Department of Nuclear Physics, University of Madras, Chennai 600025 (India)
2017-05-01
A neoteric organic third order nonlinear optical material 8-hydroxyquinolinium 2-chloro-5-nitrobenzoate dihydrate (8HQ2C5N) was grown by slow cooling technique using ethanol: water (1:1) mixed solvent. The calculated low value of average etch pit solidity (4.12 × 10{sup 3} cm{sup −2}) indicated that the title crystal contain less defects. From the single crystal X-ray diffraction data, it was endowed that 8HQ2C5N crystal belongs to the monoclinic system with centrosymmetric space group P2{sub 1}/c and the cell parameters values, a = 9.6546 (4) Ǻ, b = 7.1637(3) Ǻ, c = 24.3606 (12) Ǻ, α = γ = 90°, β = 92.458(2)° and volume = 1683.29(13) Ǻ{sup 3}. The FT-IR and FT-Raman spectrum were used to affirm the functional group of the title compound. The chemical structure of 8HQ2C5N was scrutinized by {sup 13}C and {sup 1}H NMR spectral analysis and thermal stability through the differential scanning calorimetry study. Using optical studies the lower cut-off wavelength and optical band gap of 8HQ2C5N were found to be 364 nm and 3.17 eV respectively. Using the single oscillator model suggested by Wemple – Didomenico, the oscillator energy (E{sub o}), the dispersion energy (E{sub d}) and static dielectric constant (ε{sub o}) were estimated. The third-order susceptibility were determined as Im χ{sup (3)} = 2.51 × 10{sup −5} esu and Re χ{sup (3)} = 4.46 × 10{sup −7} esu. The theoretical third-order nonlinear optical susceptibility χ{sup (3)} was calculated and the results were compared with experimental value. Photoluminescence spectrum of 8HQ2C5N crystal showed the yellow emission. The crystal had the single shot laser damage threshold of 5.562 GW/cm{sup 2}. Microhardness measurement showed that 8HQ2C5N belongs to a soft material category. - Highlights: • A new organic single crystals were grown and the crystal structure was reported. • Crystal possess, good transmittance, thermal and mechanical stability. • Single shot LDT value is found to be
Some effects of cognitive similarity on proactive and retriactive interference in short-term memory
Bunt, A.A.; Sanders, A.F.
1972-01-01
An experiment is reported on the effects of cognitive similarity on proactive and retroactive interference (PI, RI) in short term memory. To avoid confounding between cognitive and acoustic similarity, the materials - i.e. words and digits - were matched with respect to vowel pattern. Effects of
Presentation Modality and Proactive Interference in Children's Short-Term Memory.
Douglas, Joan Delahanty
This study examined the role of visual and auditory presentation in memory encoding processes of 80 second-grade children, using the release-from-proactive-interference short-term memory (STM) paradigm. Words were presented over three trials within one of the presentation modes and one taxonomic category, followed by a fourth trial in which the…
Evaluation of third order nonlinear optical parameters of CdS/PVA nanocomposite
Energy Technology Data Exchange (ETDEWEB)
Sharma, Mamta [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh-160014 (India); Department of Applied Sciences (Physics), UIET, Panjab University, Chandigarh-160014 (India); Tripathi, S. K., E-mail: surya@pu.ac.in, E-mail: surya-tr@yahoo.com [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh-160014 (India)
2015-06-24
CdS nanoparticles dispersed in PVA are prepared by Chemical method at room temperature. The nonlinear optical parameters such as nonlinear absorption (β), nonlinear refractive index (n{sub 2}) and nonlinear susceptibility (χ{sup 3}) are calculated for this sample by using Z-scan technique. CdS/PVA samples show the two photon absorption mechanism. The third order nonlinear susceptibility is calculated from n{sub 2} and β and is found to be of the order of 10{sup −7} – 10{sup −8} m{sup 2}/V{sup 2}. The larger value of third order nonlinear susceptibility is due to dielectric and quantum confinement effect.
Directory of Open Access Journals (Sweden)
C. Torres-Torres
2012-01-01
Full Text Available We report the transmittance modulation of optical signals in a nanocomposite integrated by two different silver doped zinc oxide thin solid films. An ultrasonic spray pyrolysis approach was employed for the preparation of the samples. Measurements of the third-order nonlinear optical response at a nonresonant 532 nm wavelength of excitation were performed using a vectorial two-wave mixing. It seems that the separated contribution of the optical nonlinearity associated with each film noticeable differs in the resulting nonlinear effects with respect to the additive response exhibited by the bilayer system. An enhancement of the optical Kerr nonlinearity is predicted for prime number arrays of the studied nanoclusters in a two-wave interaction. We consider that the nanostructured morphology of the thin solid films originates a strong modification of the third-order optical phenomena exhibited by multilayer films based on zinc oxide.
Computationally efficient near-field source localization using third-order moments
Chen, Jian; Liu, Guohong; Sun, Xiaoying
2014-12-01
In this paper, a third-order moment-based estimation of signal parameters via rotational invariance techniques (ESPRIT) algorithm is proposed for passive localization of near-field sources. By properly choosing sensor outputs of the symmetric uniform linear array, two special third-order moment matrices are constructed, in which the steering matrix is the function of electric angle γ, while the rotational factor is the function of electric angles γ and ϕ. With the singular value decomposition (SVD) operation, all direction-of-arrivals (DOAs) are estimated from a polynomial rooting version. After substituting the DOA information into the steering matrix, the rotational factor is determined via the total least squares (TLS) version, and the related range estimations are performed. Compared with the high-order ESPRIT method, the proposed algorithm requires a lower computational burden, and it avoids the parameter-match procedure. Computer simulations are carried out to demonstrate the performance of the proposed algorithm.
The third-order nonlinear optical susceptibility of C{sub 60}-derived nanotubes
Energy Technology Data Exchange (ETDEWEB)
Xiangang, Wan [Nanjing Univ. (China). National Lab. of Solid State Microstructures; [Center for Advanced Studies in Science and Technology of Microstructures, Nanjing (China); Jinming, Dong [Nanjing Univ. (China). National Lab. of Solid State Microstructures; [Center for Advanced Studies in Science and Technology of Microstructures, Nanjing (China); Jie, Jiang [Nanjing Univ., JS (China). Dept. of Physics; Xing, D Y [Nanjing Univ., JS (China). Dept. of Physics
1997-02-01
Using the extended Su-Schrieffer-Heeger (SSH) model and the sum-over-state (SOS) method, we have calculated the third-order nonlinear polarizability {gamma} and its dispersion spectra for C{sub 60}-derived nanotubes, which is one of the narrowest tubes. Our numerical calculations indicate that both symmetry and size of the nanotubes have great effect on the third-order nonlinear polarizability {gamma} spectra. We find that with increasing size, both static {gamma} values and dynamical response peak values increase. When the atom number of the C{sub 60}-derived nanotubes is 140, the static {gamma} value is about 65 times larger than that of C{sub 60}, and the highest peak value of {gamma} (at 3{omega} = 3.52 eV) is about three orders larger than that of C{sub 60}. So, C{sub 60}-derived nanotubes may become a kind of good nonlinear optical materials. (orig.)
Third-order nonlinearity of Er3+-doped lead phosphate glass
Energy Technology Data Exchange (ETDEWEB)
Santos, C. C. [Universidade Federal do Ceara, Ceara, Brazil; Guedes Da Silva, Ilde [ORNL; Siqueira, J. P. [Instituto de Física de São Carlos, Universidade de São Paulo, Brazil; Misoguti, L. [Instituto de Física de São Carlos, Universidade de São Paulo, Brazil; Zilio, S. C. [Instituto de Física de São Carlos, Universidade de São Paulo, Brazil; Boatner, Lynn A [ORNL
2010-01-01
The third-order optical susceptibility and dispersion of the linear refractive index of Er3+-doped lead phosphate glass were measured in the wavelength range between 400 and 1940 nm by using the spectrally resolved femtosecond Maker fringes technique. The nonlinear refractive index obtained from the third-order susceptibility was found to be five times higher than that of silica, indicating that Er3+-doped lead phosphate glass is a potential candidate to be used as the base component for the fabrication of photonic devices. For comparison purposes, the Z-scan technique was also employed to obtain the values of the nonlinear refractive index of E-doped lead phosphate glass at several wavelengths, and the values obtained using the two techniques agree to within 15%.
Zeolite Y Films as Ideal Platform for Evaluation of Third-Order Nonlinear Optical Quantum Dots
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Hyun Sung Kim
2016-01-01
Full Text Available Zeolites are ideal host material for generation and stabilization of regular ultrasmall quantum dots (QDs array with the size below 1.5 nm. Quantum dots (QDs with high density and extinction absorption coefficient have been expected to give high level of third-order nonlinear optical (3rd-NLO and to have great potential applications in optoelectronics. In this paper, we carried out a systematic elucidation of the third-order nonlinear optical response of various types of QDs including PbSe, PbS, CdSe, CdS, ZnSe, ZnS, Ag2Se, and Ag2S by manipulation of QDs into zeolites Y pores. In this respect, we could demonstrate that the zeolite offers an ideal platform for capability comparison 3rd-NLO response of various types of QDs with high sensitivities.
Models for Master-Slave Clock Distribution Networks with Third-Order Phase-Locked Loops
Piqueira, José Roberto Castilho; de Carvalho Freschi, Marcela
2007-01-01
The purpose of this work is to study the processing and transmission of clock signals in networks of geographically distributed nodes, in order to derive conditions for frequency and phase synchronization between the nodes. The focus is on the master-slave architecture, which presents a priority scheme of clock distribution. One-way master-slave (OWMS ) and two-way master-slave (TWMS) chains are studied, considering that the slave nodes are third-order phase-locked loops...
Comparison of second and third orders Runge-Kutta methods for ...
African Journals Online (AJOL)
This work is concerned with the analysis of second and third orders Runge- Kutta formulae capable of solving initial value problems in Ordinary Differential Equations of the form: y1 = f(x, y), y(x0) = y0, a £ x £ b. The intention is to find out which of these two orders can improve the performance of results when implemented ...
Third order mode laser diode: design of a twin photon source
International Nuclear Information System (INIS)
Ducci, S.; Berger, V.; Rossi, A. de; Ortiz, V.; Calligaro, M.; Vinter, B.; Nagle, J.; Berger, V.
2004-01-01
We demonstrate the lasing action on a third order waveguide mode in a laser diode. The AlGaAs heterostructure has been designed to achieve a parametric emission of photons pairs through modal phase matching. This device is very compact and does not generate coupling loss between the laser source and the non-linear waveguide. It is the first step on the way to design a twin photon micro-source. (A.C.)
Symplectic and trigonometrically fitted symplectic methods of second and third order
International Nuclear Information System (INIS)
Monovasilis, Th.; Simos, T.E.
2006-01-01
The numerical integration of Hamiltonian systems by symplectic and trigonometrically symplectic method is considered in this Letter. We construct new symplectic and trigonometrically symplectic methods of second and third order. We apply our new methods as well as other existing methods to the numerical integration of the harmonic oscillator, the 2D harmonic oscillator with an integer frequency ratio and an orbit problem studied by Stiefel and Bettis
Enhancement of third-order harmonic generation by interaction of two IR femtosecond filaments
International Nuclear Information System (INIS)
Liu, Z Y; Ding, P J; Shi, Y C; Lu, X; Liu, Q C; Sun, S H; Ding, B W; Hu, B T; Liu, X L
2012-01-01
Three orders of magnitude in the enhancement of the third-order harmonic (TH) generation induced by the interaction of two femtosecond filaments crossing with small angles in the air is achieved. The dependences of the TH generation on the time delay, the relative polarization, the input laser intensity ratios between the probe and pump beam are measured with the crossing angle of 3.5deg , and the results with quasi-vertical crossing angle are also shown for comparison
Third order effects generated by refractive lenses on sub 20 femtosecond optical pulses
International Nuclear Information System (INIS)
Estrada-Silva, F C; Rosete-Aguilar, M; Garduno-Mejia, J; Gonzalez-Galicia, M A; Bruce, N C; Ortega-Martinez, R
2011-01-01
When using lenses to focus ultra-short pulses, chromatic aberration produces pulse spreading, after propagation through the lens. The focusing of ultra-short pulses has been analyzed by using Fourier optics where the field amplitude of the pulse is evaluated around the focal region of the lens by performing a third order expansion on the wave number around the central frequency of the carrier. In the literature, the pulse focusing in the neighborhood of the focal region of the lens has been calculated by expanding the wave number up to second order. The second order approximation works for pulses with a duration greater than 20fs, or pulses propagating through low dispersion materials; but, it is necessary to do third order approximation for pulses with a shorter duration, or propagating through highly dispersive materials. In this paper we analyze 15fs and 20fs pulses, with a carrier wavelength of 810nm, at the paraxial focal plane of singlets and achromatic doublets. The analysis includes the third order GVD and the results are compared with those obtained when the wave number is expanded up to second order.
Oscillation criteria for third order nonlinear delay differential equations with damping
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Said R. Grace
2015-01-01
Full Text Available This note is concerned with the oscillation of third order nonlinear delay differential equations of the form \\[\\label{*} \\left( r_{2}(t\\left( r_{1}(ty^{\\prime}(t\\right^{\\prime}\\right^{\\prime}+p(ty^{\\prime}(t+q(tf(y(g(t=0.\\tag{\\(\\ast\\}\\] In the papers [A. Tiryaki, M. F. Aktas, Oscillation criteria of a certain class of third order nonlinear delay differential equations with damping, J. Math. Anal. Appl. 325 (2007, 54-68] and [M. F. Aktas, A. Tiryaki, A. Zafer, Oscillation criteria for third order nonlinear functional differential equations, Applied Math. Letters 23 (2010, 756-762], the authors established some sufficient conditions which insure that any solution of equation (\\(\\ast\\ oscillates or converges to zero, provided that the second order equation \\[\\left( r_{2}(tz^{\\prime }(t\\right^{\\prime}+\\left(p(t/r_{1}(t\\right z(t=0\\tag{\\(\\ast\\ast\\}\\] is nonoscillatory. Here, we shall improve and unify the results given in the above mentioned papers and present some new sufficient conditions which insure that any solution of equation (\\(\\ast\\ oscillates if equation (\\(\\ast\\ast\\ is nonoscillatory. We also establish results for the oscillation of equation (\\(\\ast\\ when equation (\\(\\ast\\ast\\ is oscillatory.
International Nuclear Information System (INIS)
Sun, Ru; Lu, Yue-Ting; Yan, Bao-Long; Lu, Jian-Mei; Wu, Xing-Zhi; Song, Ying-Lin; Ge, Jian-Feng
2014-01-01
The third-order nonlinear optical properties of poly(methyl methacrylate) films doped with charge flowable 3,7-di(piperidinyl)phenothiazin-5-ium chloride, which tested by Z-scan method with nanosecond laser beam at 532 nm, are reported. Large third-order nonlinear optical susceptibilities (up to 10 −7 esu) and high second hyperpolarizabilities (up to 10 −27 esu) are found. The third-order nonlinear absorptions change from reverse saturated absorptions to saturated absorptions with different percentage of the phenothiazinium dye in the poly(methyl methacrylate) films, which can be explained by the accumulation phenomenon of the phenothiazinium. The results suggest that the phenothiazinium salt is a promising material for third order non-linear applications. - Highlights: • Phenothiazinium containing optical films • Strong third-order nonlinear optical (NLO) absorption • Large third-order NLO susceptibilities
Alcaráz, Mirta R; Bortolato, Santiago A; Goicoechea, Héctor C; Olivieri, Alejandro C
2015-03-01
Matrix augmentation is regularly employed in extended multivariate curve resolution-alternating least-squares (MCR-ALS), as applied to analytical calibration based on second- and third-order data. However, this highly useful concept has almost no correspondence in parallel factor analysis (PARAFAC) of third-order data. In the present work, we propose a strategy to process third-order chromatographic data with matrix fluorescence detection, based on an Augmented PARAFAC model. The latter involves decomposition of a three-way data array augmented along the elution time mode with data for the calibration samples and for each of the test samples. A set of excitation-emission fluorescence matrices, measured at different chromatographic elution times for drinking water samples, containing three fluoroquinolones and uncalibrated interferences, were evaluated using this approach. Augmented PARAFAC exploits the second-order advantage, even in the presence of significant changes in chromatographic profiles from run to run. The obtained relative errors of prediction were ca. 10 % for ofloxacin, ciprofloxacin, and danofloxacin, with a significant enhancement in analytical figures of merit in comparison with previous reports. The results are compared with those furnished by MCR-ALS.
Energy Technology Data Exchange (ETDEWEB)
Cobb, J.W.
1995-02-01
There is an increasing need for more accurate numerical methods for large-scale nonlinear magneto-fluid turbulence calculations. These methods should not only increase the current state of the art in terms of accuracy, but should also continue to optimize other desired properties such as simplicity, minimized computation, minimized memory requirements, and robust stability. This includes the ability to stably solve stiff problems with long time-steps. This work discusses a general methodology for deriving higher-order numerical methods. It also discusses how the selection of various choices can affect the desired properties. The explicit discussion focuses on third-order Runge-Kutta methods, including general solutions and five examples. The study investigates the linear numerical analysis of these methods, including their accuracy, general stability, and stiff stability. Additional appendices discuss linear multistep methods, discuss directions for further work, and exhibit numerical analysis results for some other commonly used lower-order methods.
Interplay between Graph Topology and Correlations of Third Order in Spiking Neuronal Networks.
Directory of Open Access Journals (Sweden)
Stojan Jovanović
2016-06-01
Full Text Available The study of processes evolving on networks has recently become a very popular research field, not only because of the rich mathematical theory that underpins it, but also because of its many possible applications, a number of them in the field of biology. Indeed, molecular signaling pathways, gene regulation, predator-prey interactions and the communication between neurons in the brain can be seen as examples of networks with complex dynamics. The properties of such dynamics depend largely on the topology of the underlying network graph. In this work, we want to answer the following question: Knowing network connectivity, what can be said about the level of third-order correlations that will characterize the network dynamics? We consider a linear point process as a model for pulse-coded, or spiking activity in a neuronal network. Using recent results from theory of such processes, we study third-order correlations between spike trains in such a system and explain which features of the network graph (i.e. which topological motifs are responsible for their emergence. Comparing two different models of network topology-random networks of Erdős-Rényi type and networks with highly interconnected hubs-we find that, in random networks, the average measure of third-order correlations does not depend on the local connectivity properties, but rather on global parameters, such as the connection probability. This, however, ceases to be the case in networks with a geometric out-degree distribution, where topological specificities have a strong impact on average correlations.
Interplay between Graph Topology and Correlations of Third Order in Spiking Neuronal Networks.
Jovanović, Stojan; Rotter, Stefan
2016-06-01
The study of processes evolving on networks has recently become a very popular research field, not only because of the rich mathematical theory that underpins it, but also because of its many possible applications, a number of them in the field of biology. Indeed, molecular signaling pathways, gene regulation, predator-prey interactions and the communication between neurons in the brain can be seen as examples of networks with complex dynamics. The properties of such dynamics depend largely on the topology of the underlying network graph. In this work, we want to answer the following question: Knowing network connectivity, what can be said about the level of third-order correlations that will characterize the network dynamics? We consider a linear point process as a model for pulse-coded, or spiking activity in a neuronal network. Using recent results from theory of such processes, we study third-order correlations between spike trains in such a system and explain which features of the network graph (i.e. which topological motifs) are responsible for their emergence. Comparing two different models of network topology-random networks of Erdős-Rényi type and networks with highly interconnected hubs-we find that, in random networks, the average measure of third-order correlations does not depend on the local connectivity properties, but rather on global parameters, such as the connection probability. This, however, ceases to be the case in networks with a geometric out-degree distribution, where topological specificities have a strong impact on average correlations.
Limit cycles from a cubic reversible system via the third-order averaging method
Directory of Open Access Journals (Sweden)
Linping Peng
2015-04-01
Full Text Available This article concerns the bifurcation of limit cycles from a cubic integrable and non-Hamiltonian system. By using the averaging theory of the first and second orders, we show that under any small cubic homogeneous perturbation, at most two limit cycles bifurcate from the period annulus of the unperturbed system, and this upper bound is sharp. By using the averaging theory of the third order, we show that two is also the maximal number of limit cycles emerging from the period annulus of the unperturbed system.
First integrals and parametric solutions of third-order ODEs admitting {\\mathfrak{sl}(2, {R})}
Ruiz, A.; Muriel, C.
2017-05-01
A complete set of first integrals for any third-order ordinary differential equation admitting a Lie symmetry algebra isomorphic to sl(2, {R}) is explicitly computed. These first integrals are derived from two linearly independent solutions of a linear second-order ODE, without additional integration. The general solution in parametric form can be obtained by using the computed first integrals. The study includes a parallel analysis of the four inequivalent realizations of sl(2, {R}) , and it is applied to several particular examples. These include the generalized Chazy equation, as well as an example of an equation which admits the most complicated of the four inequivalent realizations.
Third-order WKBJ eigenvalues for Lennard-Jones and Varshni V potentials
International Nuclear Information System (INIS)
Kesarwani, R.N.; Varshni, Y.P.
1978-01-01
The WKBJ method is applied to the third order for obtaining the eigenvalues for the fifth potential of Varshni, and the relevant integrals are analytically evaluated. Numerical results are obtained for the Lennard-Jones Potential, which is a special case of the Varshni V potential, and are compared to the results of Harrison and Bernstein obtained by a numerical integration of the wave equation. Error estimates are made. It is shown that for diatomic potentials, the Langer correction is not needed if the WKBJ approximation is carried to second and higher orders. (author)
Nonlinear absorption and receptivity of the third order in InAs infrared region
International Nuclear Information System (INIS)
Musayev, M.A.
2005-01-01
Nonlinear absorption and receptivity of the third order and coefficient nonlinear absorption in InAs n-type with different degree of alloying was measured. Obtained score considerably exceed sense, calculated on the basis of the models describing nonlinear receptivity of electrons, situated in the nonparabolic area of conductivity. It was shown that, observable deviations withdraw; if in the calculation apply energy dissipation of electrons. Growth of the efficiency under four-wave interaction in low-energy-gap semiconductors confines nonlinear absorption of interacting waves
Third-order perturbation theory for van der Waals interaction coefficients
International Nuclear Information System (INIS)
Tang Liyan; Shi Tingyun; Yan Zongchao; Mitroy, J.
2011-01-01
The third-order expression for the dispersion interaction between two atoms is written as a sum over lists of transition matrix elements. Particular attention is given to the C 9 /R 9 interaction which occurs in the homonuclear case when one atom is in an S state and the other is in a P state. Numerical values of the C 9 coefficient are given for the homonuclear alkali-metal dimers. The size of the C 9 :C 3 dispersion coefficient ratio increases for the heavier alkali-metal atoms. The C 11 and C 13 coefficients between two helium atoms and lithium atoms in their ground states are also given.
Third-order TRANSPORT: A computer program for designing charged particle beam transport systems
International Nuclear Information System (INIS)
Carey, D.C.; Brown, K.L.; Rothacker, F.
1995-05-01
TRANSPORT has been in existence in various evolutionary versions since 1963. The present version of TRANSPORT is a first-, second-, and third-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems. This report discusses the following topics on TRANSPORT: Mathematical formulation of TRANSPORT; input format for TRANSPORT; summaries of TRANSPORT elements; preliminary specifications; description of the beam; physical elements; other transformations; assembling beam lines; operations; variation of parameters for fitting; and available constraints -- the FIT command
Chaos control of third-order phase-locked loops using backstepping nonlinear controller
International Nuclear Information System (INIS)
Harb, Ahmad M.; Harb, Bassam A.
2004-01-01
Previous study showed that a third-order phase-locked loop (PLL) with sinusoidal phase detector characteristics experienced a Hopf bifurcation point as well as chaotic behavior. As a result, this behavior drives the PLL to the out-of-lock (unstable) state. The analysis was based on a modern nonlinear theory such as bifurcation and chaos. The main goal of this paper is to control this chaotic behavior. A nonlinear controller based on the theory of backstepping is designed. The study showed the effectiveness of the designed nonlinear controller in controlling the undesirable unstable behavior and pulling the PLL back to the in-lock state
Third-order correlator for measuring the time profile of petawatt laser pulses
Energy Technology Data Exchange (ETDEWEB)
Ginzburg, V N; Lozhkarev, V V; Luchinin, G A; Mironov, S Yu; Khazanov, Efim A; Yakovlev, I V [Institute of Applied Physics, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation); Didenko, N V; Konyashchenko, Aleksandr V; Lutsenko, Andrei P [' Avesta-project' Ltd., Troitsk, Moscow Region (Russian Federation)
2008-11-30
A third-order correlator with a single-shot time window and a full dynamic range of 10{sup 8} is developed. The time contrast of radiation from the front-end system of a petawatt femtosecond laser complex measured with the correlator within time windows {+-}1 ps and {+-}100 ps was 10{sup 4} and more than 10{sup 8}, respectively. Based on the theoretical analysis of the cross-correlator operation, a number of requirements providing the optimal functioning of the cross-correlator are found. The reasons restricting the technical parameters of the correlator are discussed. (measurement of parameters of laser radiation)
Dynamical Tangles in Third-Order Oscillator with Single Jump Function
Directory of Open Access Journals (Sweden)
Jiří Petržela
2014-01-01
Full Text Available This contribution brings a deep and detailed study of the dynamical behavior associated with nonlinear oscillator described by a single third-order differential equation with scalar jump nonlinearity. The relative primitive geometry of the vector field allows making an exhaustive numerical analysis of its possible solutions, visualizations of the invariant manifolds, and basins of attraction as well as proving the existence of chaotic motion by using the concept of both Shilnikov theorems. The aim of this paper is also to complete, carry out and link the previous works on simple Newtonian dynamics, and answer the question how individual types of the phenomenon evolve with time via understandable notes.
Third-order correlator for measuring the time profile of petawatt laser pulses
International Nuclear Information System (INIS)
Ginzburg, V N; Lozhkarev, V V; Luchinin, G A; Mironov, S Yu; Khazanov, Efim A; Yakovlev, I V; Didenko, N V; Konyashchenko, Aleksandr V; Lutsenko, Andrei P
2008-01-01
A third-order correlator with a single-shot time window and a full dynamic range of 10 8 is developed. The time contrast of radiation from the front-end system of a petawatt femtosecond laser complex measured with the correlator within time windows ±1 ps and ±100 ps was 10 4 and more than 10 8 , respectively. Based on the theoretical analysis of the cross-correlator operation, a number of requirements providing the optimal functioning of the cross-correlator are found. The reasons restricting the technical parameters of the correlator are discussed. (measurement of parameters of laser radiation)
Grouping influences output interference in short-term memory: a mixture modeling study
Directory of Open Access Journals (Sweden)
Min-Suk eKang
2016-05-01
Full Text Available Output interference is a source of forgetting induced by recalling. We investigated how grouping influences output interference in short-term memory. In Experiment 1, the participants were asked to remember four colored items. Those items were grouped by temporal coincidence as well as spatial alignment: two items were presented in the first memory array and two were presented in the second, and the items in both arrays were either vertically or horizontally aligned as well. The participants then performed two recall tasks in sequence by selecting a color presented at a cued location from a color wheel. In the same-group condition, the participants reported both items from the same memory array; however, in the different-group condition, the participants reported one item from each memory array. We analyzed participant responses with a mixture model, which yielded two measures: guess rate and precision of recalled memories. The guess rate in the second recall was higher for the different-group condition than for the same-group condition; however, the memory precisions obtained for both conditions were similarly degraded in the second recall. In Experiment 2, we varied the probability of the same- and different-group conditions with a ratio of 3 to 7. We expected output interference to be higher in the same-group condition than in the different-group condition. This is because items of the other group are more likely to be probed in the second recall phase and, thus, protecting those items during the first recall phase leads to a better performance. Nevertheless, the same pattern of results was robustly reproduced, suggesting grouping shields the grouped items from output interference because of the secured accessibility. We discussed how grouping influences output interference.
2016-07-04
required analysis, and further testing. 15. SUBJECT TERMS Adjacent Channel Interference, ACI, LTE -A, LTE , PCM/FM, SOQPSK-TG, ARTM CPM, AWS-3, User...Interference, ACI, LTE -A, LTE , PCM/FM, SOQPSK-TG, ARTM CPM, AWS-3, User Equipment, UE, Evolved Node B, eNodeB, Resource Blocks INTRODUCTION “On...these questions make necessary an improved understanding of the interferers that can be obtained only by hands-on measurements . This work will
International Nuclear Information System (INIS)
Ghosh, Binita; Chakraborty, Purushottam
2011-01-01
Silver ion implantations in fused silica glasses have been made to synthesize silver nanocluster-glass composites and a combination of 'Anti-Resonant Interferometric Nonlinear Spectroscopy (ARINS)' and 'Z-scan' techniques has been employed for the measurement of the third-order optical susceptibility of these nanocomposites. The ARINS technique utilizes the dressing of two unequal-intensity counter-propagating pulsed optical beams with differential nonlinear phases, which occurs upon traversing the sample. This difference in phase manifests itself in the intensity-dependent transmission, measurement of which enables us to extract the values of nonlinear refractive index (η 2 ) and nonlinear absorption coefficient (β), finally yielding the real and imaginary parts of the third-order dielectric susceptibility (χ (3) ). The real and imaginary parts of χ (3) are obtained in the orders of 10 -10 e.s.u for silver nanocluster-glass composites. The present value of χ (3) , to our knowledge, is extremely accurate and much more reliable compared to the values previously obtained by other workers for similar silver-glass nanocomposites using only Z-scan technique. Optical nonlinearity has been explained to be due to two-photon absorption in the present nanocomposite glasses and is essentially of electronic origin.
Rani, Sunita; Mohan, Devendra; Kumar, Manish; Sanjay
2018-05-01
Third order nonlinear susceptibility of (GeSe3.5)100-xBix (x = 0, 10, 14) and ZnxSySe100-x-y (x = 2, y = 28; x = 4, y = 20; x = 6, y = 12; x = 8, y = 4) amorphous chalcogenide thin films prepared using thermal evaporation technique is estimated. The dielectric constant at incident and third harmonic wavelength is calculated using "PARAV" computer program. 1064 nm wavelength of Nd: YAG laser is incident on thin film and third harmonic signal at 355 nm wavelength alongwith fundamental light is obtained in reflection that is separated from 1064 nm using suitable optical filter. Reflected third harmonic signal is measured to trace the influence of Bi and Zn on third order nonlinear susceptibility and is found to increase with increase in Bi and Zn content in (GeSe3.5)100-xBix, and ZnxSySe100-x-y chalcogenide thin films respectively. The excellent optical nonlinear property shows the use of chalcogenide thin films in photonics for wavelength conversion and optical data processing.
Multi-objective optimization of GPU3 Stirling engine using third order analysis
International Nuclear Information System (INIS)
Toghyani, Somayeh; Kasaeian, Alibakhsh; Hashemabadi, Seyyed Hasan; Salimi, Morteza
2014-01-01
Highlights: • A third-order analysis is carried out for optimization of Stirling engine. • The triple-optimization is done on a GPU3 Stirling engine. • A multi-objective optimization is carried out for a Stirling engine. • The results are compared with an experimental previous work for checking the model improvement. • The methods of TOPSIS, Fuzzy, and LINMAP are compared with each other in aspect of optimization. - Abstract: Stirling engine is an external combustion engine that uses any external heat source to generate mechanical power which operates at closed cycles. These engines are good choices for using in power generation systems; because these engines present a reasonable theoretical efficiency which can be closer to the Carnot efficiency, comparing with other reciprocating thermal engines. Hence, many studies have been conducted on Stirling engines and the third order thermodynamic analysis is one of them. In this study, multi-objective optimization with four decision variables including the temperature of heat source, stroke, mean effective pressure, and the engine frequency were applied in order to increase the efficiency and output power and reduce the pressure drop. Three decision-making procedures were applied to optimize the answers from the results. At last, the applied methods were compared with the results obtained of one experimental work and a good agreement was observed
A third-order asymptotic solution of nonlinear standing water waves in Lagrangian coordinates
International Nuclear Information System (INIS)
Yang-Yih, Chen; Hung-Chu, Hsu
2009-01-01
Asymptotic solutions up to third-order which describe irrotational finite amplitude standing waves are derived in Lagrangian coordinates. The analytical Lagrangian solution that is uniformly valid for large times satisfies the irrotational condition and the pressure p = 0 at the free surface, which is in contrast with the Eulerian solution existing under a residual pressure at the free surface due to Taylor's series expansion. In the third-order Lagrangian approximation, the explicit parametric equation and the Lagrangian wave frequency of water particles could be obtained. In particular, the Lagrangian mean level of a particle motion that is a function of vertical label is found as a part of the solution which is different from that in an Eulerian description. The dynamic properties of nonlinear standing waves in water of a finite depth, including particle trajectory, surface profile and wave pressure are investigated. It is also shown that the Lagrangian solution is superior to an Eulerian solution of the same order for describing the wave shape and the kinematics above the mean water level. (general)
The Effects of Age on Short-Term Memory Loss due to Proactive Interference
Alisha Berkauzer
2011-01-01
This project focused on how proactive interference affects the short-term memory of people based on their age. The goal was to find the prime age for learning information and storing it in one's memory. Seven people from ages fifteen to forty were tested individually, using a set color pattern, in order to see how well each individual could remember the different color patterns as difficulty of the pattern increased. The obtained data was fitted by the polynomial regression. The “fitted...
International Nuclear Information System (INIS)
Li Yong; Lu Jing; Cui Xiaobing; Xu Jiqing; Li Kechang; Sun Huaying; Li Guanghua; Pan Lingyun; Yang Qingxin
2005-01-01
Both the homometal cluster [P(ph 4 )] 2 [Mo 2 O 2 (μ-S) 2 (S 2 ) 2 ] (1) and [Mo 2 O 2 (μ-S) 2 (Et 2 dtc) 2 ] (2) (Et 2 dtc=diethyl-dithiocarbamate) were successfully synthesized by low-temperature solid-state reactions. X-ray single-crystal diffraction studies suggest that compound (1) is a dinuclear anion cluster, and compound (2) is a dinuclear neutral cluster. The two compounds were characterized by elemental analyses, IR spectra and UV-Vis spectra. The third-order non-linear optical (NLO) properties of the clusters were also investigated and all exhibited nice non-linear absorption and self-defocusing performance with moduli of the hyperpolarizabilities 5.145x10 -30 esu for (1) and 5.428x10 -30 esu for (2)
Diophantine non-integrability of a third-order recurrence with the Laurent property
International Nuclear Information System (INIS)
Hone, A N W
2006-01-01
We consider a one-parameter family of third-order nonlinear recurrence relations. Each member of this family satisfies the singularity confinement test, has a conserved quantity, and moreover has the Laurent property: all of the iterates are Laurent polynomials in the initial data. However, we show that these recurrences are not Diophantine integrable according to the definition proposed by Halburd (2005 J. Phys. A: Math. Gen. 38 L1). Explicit bounds on the asymptotic growth of the heights of iterates are obtained for a special choice of initial data. As a by-product of our analysis, infinitely many solutions are found for a certain family of Diophantine equations, studied by Mordell, that includes Markoff's equation. (letter to the editor)
Third-order perturbation theory for van der Waals interaction coefficients
Energy Technology Data Exchange (ETDEWEB)
Tang Liyan; Shi Tingyun [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Yan Zongchao [Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071 (China); Department of Physics, Wuhan University, Wuhan 430072 (China); Department of Physics, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3 (Canada); Mitroy, J. [School of Engineering, Charles Darwin University, Darwin NT 0909 (Australia)
2011-11-15
The third-order expression for the dispersion interaction between two atoms is written as a sum over lists of transition matrix elements. Particular attention is given to the C{sub 9}/R{sup 9} interaction which occurs in the homonuclear case when one atom is in an S state and the other is in a P state. Numerical values of the C{sub 9} coefficient are given for the homonuclear alkali-metal dimers. The size of the C{sub 9}:C{sub 3} dispersion coefficient ratio increases for the heavier alkali-metal atoms. The C{sub 11} and C{sub 13} coefficients between two helium atoms and lithium atoms in their ground states are also given.
Third-order polynomial model for analyzing stickup state laminated structure in flexible electronics
Meng, Xianhong; Wang, Zihao; Liu, Boya; Wang, Shuodao
2018-02-01
Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded, twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Third-order polynomials are used to describe the displacement field, and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bi-material region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future.
International Nuclear Information System (INIS)
Pelinovsky, Dmitry E.; Yang Jianke
2005-01-01
We study the generalized third-order nonlinear Schroedinger (NLS) equation which admits a one-parameter family of single-hump embedded solitons. Analyzing the spectrum of the linearization operator near the embedded soliton, we show that there exists a resonance pole in the left half-plane of the spectral parameter, which explains linear stability, rather than nonlinear semistability, of embedded solitons. Using exponentially weighted spaces, we approximate the resonance pole both analytically and numerically. We confirm in a near-integrable asymptotic limit that the resonance pole gives precisely the linear decay rate of parameters of the embedded soliton. Using conserved quantities, we qualitatively characterize the stable dynamics of embedded solitons
International Nuclear Information System (INIS)
Srivastava, A.C.; Hazarika, G.C.
1990-01-01
An algorithm based on the shooting method has been developed for the solution of a two-point boundary value problem consisting of a system of third order simultaneous ordinary differential equations. The Falkner-Skan equations for electrically conducting viscous fluid with applied magnetic field has been solved by using this algorithm for various values of the wedge angle and magnetic parameters. The shooting method seems to be well convergent for a system as the results are in good agreement with those obtained by other methods. It is observed that both viscous boundary layer and magnetic boundary layer decrease while velocity as well as magnetic field increase with the increase of the wedge angle. (author). 6 tabs., 7 refs
Third-order nonlinear optical studies of anthraquinone dyes using a CW He–Ne laser
International Nuclear Information System (INIS)
Pramodini, S; Poornesh, P
2014-01-01
We present investigations on the third-order optical nonlinearity and optical power limiting of anthraquinone dyes. Z-scan measurements were performed using a continuous wave He–Ne laser at 633 nm wavelength as an excitation source. The nonlinear refraction studies exhibited self-defocusing behavior of the dyes. The nonlinear absorption in the dyes was dominated by a reverse saturable absorption process. Self-diffraction ring patterns were observed due to the change in refractive index and thermal lensing. Increase of the electron donating ability of the substituents resulted in enhanced values of the nonlinear optical parameters, establishing the structure–property relationship. The optical limiting study revealed that the dyes possess a lower limiting threshold and clamping level which is very important for eye and sensor protection. Hence, the dyes investigated here emerge as promising candidates for future opto-electronic and photonic device applications such as optical power limiters. (paper)
Third-order nonlinear optical studies of anthraquinone dyes using a CW He-Ne laser
Pramodini, S.; Poornesh, P.
2014-05-01
We present investigations on the third-order optical nonlinearity and optical power limiting of anthraquinone dyes. Z-scan measurements were performed using a continuous wave He-Ne laser at 633 nm wavelength as an excitation source. The nonlinear refraction studies exhibited self-defocusing behavior of the dyes. The nonlinear absorption in the dyes was dominated by a reverse saturable absorption process. Self-diffraction ring patterns were observed due to the change in refractive index and thermal lensing. Increase of the electron donating ability of the substituents resulted in enhanced values of the nonlinear optical parameters, establishing the structure-property relationship. The optical limiting study revealed that the dyes possess a lower limiting threshold and clamping level which is very important for eye and sensor protection. Hence, the dyes investigated here emerge as promising candidates for future opto-electronic and photonic device applications such as optical power limiters.
Hopf bifurcation and chaos in a third-order phase-locked loop
Piqueira, José Roberto C.
2017-01-01
Phase-locked loops (PLLs) are devices able to recover time signals in several engineering applications. The literature regarding their dynamical behavior is vast, specifically considering that the process of synchronization between the input signal, coming from a remote source, and the PLL local oscillation is robust. For high-frequency applications it is usual to increase the PLL order by increasing the order of the internal filter, for guarantying good transient responses; however local parameter variations imply structural instability, thus provoking a Hopf bifurcation and a route to chaos for the phase error. Here, one usual architecture for a third-order PLL is studied and a range of permitted parameters is derived, providing a rule of thumb for designers. Out of this range, a Hopf bifurcation appears and, by increasing parameters, the periodic solution originated by the Hopf bifurcation degenerates into a chaotic attractor, therefore, preventing synchronization.
Energy Technology Data Exchange (ETDEWEB)
Castro, Hemerson P. S.; Alencar, Márcio A. R. C.; Hickmann, Jandir M. [Optics and Materials Group–OPTMA, Universidade Federal de Alagoas, CAIXA POSTAL 2051, 57061-970 Maceió (Brazil); Wender, Heberton [Brazilian Synchrotron National Laboratory (LNLS), CNPEM, Rua Giuseppe Máximo Scolfaro 10.000, 13083-970 Campinas (Brazil); Department of Physics, Universidade Federal do Mato Grosso do Sul, 79070-900, Campo Grande (Brazil); Teixeira, Sergio R. [Institute of Physics, Universidade Federal do Rio Grande do Sul, 91501-970, Porto Alegre (Brazil); Dupont, Jairton [Laboratory of Molecular Catalysis, Institute of Chemistry, Universidade Federal do Rio Grande do Sul, 91501-970, Porto Alegre (Brazil)
2013-11-14
The nonlinear optical responses of gold nanoparticles dispersed in castor oil produced by sputtering deposition were investigated, using the thermally managed Z-scan technique. Particles with spherical shape and 2.6 nm of average diameter were obtained and characterized by transmission electron microscopy and small angle X-ray scattering. This colloid was highly stable, without the presence of chemical impurities, neither stabilizers. It was observed that this system presents a large refractive third-order nonlinear response and a negligible nonlinear absorption. Moreover, the evaluation of the all-optical switching figures of merit demonstrated that the colloidal nanoparticles prepared by sputtering deposition have a good potential for the development of ultrafast photonic devices.
Third-order QCD corrections to heavy quark pair production near threshold
Energy Technology Data Exchange (ETDEWEB)
Schuller, Kurt
2008-11-07
The measurement of the top quark mass is an important task at the future International Linear Collider. The most promising process is the top quark pair production in the threshold region. In this region the top quarks behave non-relativistically and a perturbative treatment using effective field theories is possible. Current second order theoretical predictions in a fixed order approach show an uncertainty which is bigger than the expected experimental errors. Therefore, an improvement of the cross section calculation is desirable. There are two ways to incorporate higher order effects, one is to calculate the full next order in the fixed order approach, another possibility is to resum large logarithms. In this work, the fixed order calculation has been extended to the third order in perturbation theory for the QCD corrections. The result is a strongly improved scale behavior and a better understanding of heavy quarkonium systems. The Green function result is given in a semi-analytic form. The energy levels and wave functions for heavy quarkonium states have been calculated from the poles of the Green function and are presented for arbitrary quantum number n. The results have been implemented in a Mathematica program which makes the data easily accessible. Once some missing matching coefficients are calculated, and a complete electroweak calculation is available, the results of this work can be used to improve the precision of the top quark mass measurement to an uncertainty of less than 50 MeV. An inclusion of initial state radiation and beam effects are essential for a realistic observable. In the future, the results obtained could be used for a third order resummation of large logarithms. Further applications are also the extraction of the bottom quark mass with sum rules. (orig.)
International Nuclear Information System (INIS)
Delfin L, A.; Alonso V, G.; Valle G, E. del
2003-01-01
In this work two nodal schemes of finite element are presented, one of second and the other of third order of accurate that allow to determine the radial distribution of power starting from the corresponding reactivities.The schemes here developed were obtained taking as starting point the equation developed by Driscoll et al, the one which is based on the diffusion approach of 1-1/2 energy groups. This equation relates the power fraction of an assemble with their reactivity and with the power fractions and reactivities of the assemblies that its surround it. Driscoll and collaborators they solve in form approximate such equation supposing that the reactivity of each assemble it is but a lineal function of the burnt one of the fuel. The spatial approach carries out it with the classic technique of finite differences centered in mesh. Nevertheless that the algebraic system to which its arrive it can be solved without more considerations introduce some additional suppositions and adjustment parameters that it allows them to predict results comparable to those contributed by three dimensions analysis and this way to reduce the one obtained error when its compare their results with those of a production code like CASMO. Also in the two schemes that here are presented the same approaches of Driscoll were used being obtained errors of the one 10% and of 5% for the second schemes and third order respectively for a test case that it was built starting from data of the Cycle 1 of the Unit 1 of the Laguna Verde Nucleo electric plant. These errors its were obtained when comparing with a computer program based on the matrix response method. It is sought to have this way a quick and efficient tool for the multicycle analysis in the fuel management. However, this model presents problems in the appropriate prediction of the average burnt of the nucleus and of the burnt one by lot. (Author)
Development and application of a third order scheme of finite differences centered in mesh
International Nuclear Information System (INIS)
Delfin L, A.; Alonso V, G.; Valle G, E. del
2003-01-01
In this work the development of a third order scheme of finite differences centered in mesh is presented and it is applied in the numerical solution of those diffusion equations in multi groups in stationary state and X Y geometry. Originally this scheme was developed by Hennart and del Valle for the monoenergetic diffusion equation with a well-known source and they show that the one scheme is of third order when comparing the numerical solution with the analytical solution of a model problem using several mesh refinements and boundary conditions. The scheme by them developed it also introduces the application of numeric quadratures to evaluate the rigidity matrices and of mass that its appear when making use of the finite elements method of Galerkin. One of the used quadratures is the open quadrature of 4 points, no-standard, of Newton-Cotes to evaluate in approximate form the elements of the rigidity matrices. The other quadrature is that of 3 points of Radau that it is used to evaluate the elements of all the mass matrices. One of the objectives of these quadratures are to eliminate the couplings among the Legendre moments 0 and 1 associated to the left and right faces as those associated to the inferior and superior faces of each cell of the discretization. The other objective is to satisfy the particles balance in weighed form in each cell. In this work it expands such development to multiplicative means considering several energy groups. There are described diverse details inherent to the technique, particularly those that refer to the simplification of the algebraic systems that appear due to the space discretization. Numerical results for several test problems are presented and are compared with those obtained with other nodal techniques. (Author)
The impact of interference on short-term memory for visual orientation.
Rademaker, Rosanne L; Bloem, Ilona M; De Weerd, Peter; Sack, Alexander T
2015-12-01
Visual short-term memory serves as an efficient buffer for maintaining no longer directly accessible information. How robust are visual memories against interference? Memory for simple visual features has proven vulnerable to distractors containing conflicting information along the relevant stimulus dimension, leading to the idea that interacting feature-specific channels at an early stage of visual processing support memory for simple visual features. Here we showed that memory for a single randomly orientated grating was susceptible to interference from a to-be-ignored distractor grating presented midway through a 3-s delay period. Memory for the initially presented orientation became noisier when it differed from the distractor orientation, and response distributions were shifted toward the distractor orientation (by ∼3°). Interestingly, when the distractor was rendered task-relevant by making it a second memory target, memory for both retained orientations showed reduced reliability as a function of increased orientation differences between them. However, the degree to which responses to the first grating shifted toward the orientation of the task-relevant second grating was much reduced. Finally, using a dichoptic display, we demonstrated that these systematic biases caused by a consciously perceived distractor disappeared once the distractor was presented outside of participants' awareness. Together, our results show that visual short-term memory for orientation can be systematically biased by interfering information that is consciously perceived. (c) 2015 APA, all rights reserved).
Decomposition of Polarimetric SAR Images Based on Second- and Third-order Statics Analysis
Kojima, S.; Hensley, S.
2012-12-01
There are many papers concerning the research of the decomposition of polerimetric SAR imagery. Most of them are based on second-order statics analysis that Freeman and Durden [1] suggested for the reflection symmetry condition that implies that the co-polarization and cross-polarization correlations are close to zero. Since then a number of improvements and enhancements have been proposed to better understand the underlying backscattering mechanisms present in polarimetric SAR images. For example, Yamaguchi et al. [2] added the helix component into Freeman's model and developed a 4 component scattering model for the non-reflection symmetry condition. In addition, Arii et al. [3] developed an adaptive model-based decomposition method that could estimate both the mean orientation angle and a degree of randomness for the canopy scattering for each pixel in a SAR image without the reflection symmetry condition. This purpose of this research is to develop a new decomposition method based on second- and third-order statics analysis to estimate the surface, dihedral, volume and helix scattering components from polarimetric SAR images without the specific assumptions concerning the model for the volume scattering. In addition, we evaluate this method by using both simulation and real UAVSAR data and compare this method with other methods. We express the volume scattering component using the wire formula and formulate the relationship equation between backscattering echo and each component such as the surface, dihedral, volume and helix via linearization based on second- and third-order statics. In third-order statics, we calculate the correlation of the correlation coefficients for each polerimetric data and get one new relationship equation to estimate each polarization component such as HH, VV and VH for the volume. As a result, the equation for the helix component in this method is the same formula as one in Yamaguchi's method. However, the equation for the volume
Energy Technology Data Exchange (ETDEWEB)
Brown, Karl
1998-10-28
TRANSPORT has been in existence in various evolutionary versions since 1963. The present version of TRANSPORT is a first-, second-, and third-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems.
Third-order non-Coulomb correction to the S-wave quarkonium wave functions at the origin
International Nuclear Information System (INIS)
Beneke, M.; Kiyo, Y.; Schuller, K.
2008-01-01
We compute the third-order correction to the S-wave quarkonium wave functions |ψ n (0)| 2 at the origin from non-Coulomb potentials in the effective non-relativistic Lagrangian. Together with previous results on the Coulomb correction and the ultrasoft correction computed in a companion paper, this completes the third-order calculation up to a few unknown matching coefficients. Numerical estimates of the new correction for bottomonium and toponium are given
International Nuclear Information System (INIS)
Fakhar, K.; Kara, A. H.
2012-01-01
We study the symmetries, conservation laws and reduction of third-order equations that evolve from a prior reduction of models that arise in fluid phenomena. These could be the ordinary differential equations (ODEs) that are reductions of partial differential equations (PDEs) or, alternatively, PDEs related to given ODEs. In this class, the analysis includes the well-known Blasius, Chazy, and other associated third-order ODEs. (general)
Third-order gas-liquid phase transition and the nature of Andrews critical point
Directory of Open Access Journals (Sweden)
Tian Ma
2011-12-01
Full Text Available The main objective of this article is to study the nature of the Andrews critical point in the gas-liquid transition in a physical-vapor transport (PVT system. A dynamical model, consistent with the van der Waals equation near the Andrews critical point, is derived. With this model, we deduce two physical parameters, which interact exactly at the Andrews critical point, and which dictate the dynamic transition behavior near the Andrews critical point. In particular, it is shown that 1 the gas-liquid co-existence curve can be extended beyond the Andrews critical point, and 2 the transition is first order before the critical point, second-order at the critical point, and third order beyond the Andrews critical point. This clearly explains why it is hard to observe the gas-liquid phase transition beyond the Andrews critical point. Furthermore, the analysis leads naturally the introduction of a general asymmetry principle of fluctuations and the preferred transition mechanism for a thermodynamic system. The theoretical results derived in this article are in agreement with the experimental results obtained in (K. Nishikawa and T. Morita, Fluid behavior at supercritical states studied by small-angle X-ray scattering, Journal of Supercritical Fluid, 13 (1998, pp. 143-148. Also, the derived second-order transition at the critical point is consistent with the result obtained in (M. Fisher, Specific heat of a gas near the critical point, Physical Review, 136:6A (1964, pp. A1599-A1604.
Physical origin of third order non-linear optical response of porphyrin nanorods
International Nuclear Information System (INIS)
Mongwaketsi, N.; Khamlich, S.; Pranaitis, M.; Sahraoui, B.; Khammar, F.; Garab, G.; Sparrow, R.; Maaza, M.
2012-01-01
The non-linear optical properties of porphyrin nanorods were studied using Z-scan, Second and Third harmonic generation techniques. We investigated in details the heteroaggregate behaviour formation of [H 4 TPPS 4 ] 2- and [SnTPyP] 2+ mixture by means of the UV-VIS spectroscopy and aggregates structure and morphology by transmission electron microscopy. The porphyrin nanorods under investigation were synthesized by self assembly and molecular recognition method. They have been optimized in view of future application in the construction of the light harvesting system. The focus of this study was geared towards understanding the influence of the type of solvent used on these porphyrins nanorods using spectroscopic and microscopic techniques. Highlights: ► We synthesized porphyrin nanorods by self assembly and molecular recognition method. ► TEM images confirmed solid cylindrical shapes. ► UV-VIS spectroscopy showed the decrease in the absorbance peaks of the precursors. ► The enhanced third-order nonlinearities were observed.
Third-order nonlinear optical response of Ag-CdSe/PVA hybrid nanocomposite
Energy Technology Data Exchange (ETDEWEB)
Tripathi, S.K.; Kaur, Ramneek; Kaur, Jaspreet; Sharma, Mamta [Panjab University, Department of Physics, Center of Advanced Study in Physics, Chandigarh (India)
2015-09-15
Hybrid nanocomposites of II-VI semiconductor nanoparticles are gaining great interest in nonlinear optoelectronic devices. Present work includes the characterization of CdSe polymer nanocomposite prepared by chemical in situ technique. From X-ray diffraction, the hexagonal wurtzite structure of nanoparticles has been confirmed with spherical morphology from transmission electron microscopy. Ag-CdSe hybrid polymer nanocomposite has been prepared chemically at different Ag concentrations. The presence of Ag in hybrid nanocomposite has been confirmed with energy-dispersive X-ray spectroscopy. The effect of varying Ag concentration on the linear and nonlinear optical properties of the nanocomposites has been studied. In linear optical parameters, the linear absorption coefficient, refractive index, extinction coefficient and optical conductivity have been calculated. The third-order nonlinear optical properties have been observed with open- and closed-aperture Z-scan technique. The large nonlinear refractive index ∝10{sup -5} cm{sup 2}/W with self-focusing behaviour is due to the combined effect of quantum confinement and thermo-optical effects. The enhanced nonlinearity with increasing Ag content is due to the surface plasmon resonance, which enhances the local electric field near the nanoparticle surface. Thus, Ag-CdSe hybrid polymer nanocomposite has favourable nonlinear optical properties for various optoelectronic applications. (orig.)
Third-order nonlinear optical response of Ag-CdSe/PVA hybrid nanocomposite
International Nuclear Information System (INIS)
Tripathi, S.K.; Kaur, Ramneek; Kaur, Jaspreet; Sharma, Mamta
2015-01-01
Hybrid nanocomposites of II-VI semiconductor nanoparticles are gaining great interest in nonlinear optoelectronic devices. Present work includes the characterization of CdSe polymer nanocomposite prepared by chemical in situ technique. From X-ray diffraction, the hexagonal wurtzite structure of nanoparticles has been confirmed with spherical morphology from transmission electron microscopy. Ag-CdSe hybrid polymer nanocomposite has been prepared chemically at different Ag concentrations. The presence of Ag in hybrid nanocomposite has been confirmed with energy-dispersive X-ray spectroscopy. The effect of varying Ag concentration on the linear and nonlinear optical properties of the nanocomposites has been studied. In linear optical parameters, the linear absorption coefficient, refractive index, extinction coefficient and optical conductivity have been calculated. The third-order nonlinear optical properties have been observed with open- and closed-aperture Z-scan technique. The large nonlinear refractive index ∝10 -5 cm 2 /W with self-focusing behaviour is due to the combined effect of quantum confinement and thermo-optical effects. The enhanced nonlinearity with increasing Ag content is due to the surface plasmon resonance, which enhances the local electric field near the nanoparticle surface. Thus, Ag-CdSe hybrid polymer nanocomposite has favourable nonlinear optical properties for various optoelectronic applications. (orig.)
Explicit formulation of second and third order optical nonlinearity in the FDTD framework
Varin, Charles; Emms, Rhys; Bart, Graeme; Fennel, Thomas; Brabec, Thomas
2018-01-01
The finite-difference time-domain (FDTD) method is a flexible and powerful technique for rigorously solving Maxwell's equations. However, three-dimensional optical nonlinearity in current commercial and research FDTD softwares requires solving iteratively an implicit form of Maxwell's equations over the entire numerical space and at each time step. Reaching numerical convergence demands significant computational resources and practical implementation often requires major modifications to the core FDTD engine. In this paper, we present an explicit method to include second and third order optical nonlinearity in the FDTD framework based on a nonlinear generalization of the Lorentz dispersion model. A formal derivation of the nonlinear Lorentz dispersion equation is equally provided, starting from the quantum mechanical equations describing nonlinear optics in the two-level approximation. With the proposed approach, numerical integration of optical nonlinearity and dispersion in FDTD is intuitive, transparent, and fully explicit. A strong-field formulation is also proposed, which opens an interesting avenue for FDTD-based modelling of the extreme nonlinear optics phenomena involved in laser filamentation and femtosecond micromachining of dielectrics.
Role of third-order dispersion in chirped Airy pulse propagation in single-mode fibers
Cai, Wangyang; Wang, Lei; Wen, Shuangchun
2018-04-01
The dynamic propagation of the initial chirped Airy pulse in single-mode fibers is studied numerically, special attention being paid to the role of the third-order dispersion (TOD). It is shown that for the positive TOD, the Airy pulse experiences inversion irrespective of the sign of initial chirp. The role of TOD in the dynamic propagation of the initial chirped Airy pulse depends on the combined sign of the group-velocity dispersion (GVD) and the initial chirp. If the GVD and chirp have the opposite signs, the chirped Airy pulse compresses first and passes through a breakdown area, then reconstructs a new Airy pattern with opposite acceleration, with the breakdown area becoming small and the main peak of the new Airy pattern becoming asymmetric with an oscillatory structure due to the positive TOD. If the GVD and chirp have the same signs, the finite-energy Airy pulse compresses to a focal point and then inverses its acceleration, in the case of positive TOD, the distance to the focal point becoming smaller. At zero-dispersion point, the finite-energy Airy pulse inverses to the opposite acceleration at a focal point, with the tight-focusing effect being reduced by initial chirp. Under the effect of negative TOD, the initial chirped Airy pulse disperses and the lobes split. In addition, in the anomalous dispersion region, for strong nonlinearity, the initial chirped Airy pulse splits and enters a soliton shedding regime.
International Nuclear Information System (INIS)
Fernández-Hernández, Roberto Carlos; Gleason-Villagran, Roberto; Rodríguez-Fernández, Luis; Crespo-Sosa, Alejandro; Cheang-Wong, Juan Carlos; López-Suárez, Alejandra; Oliver, Alicia; Reyes-Esqueda, Jorge Alejandro; Torres-Torres, Carlos; Rangel-Rojo, Raúl
2012-01-01
Au and Ag isotropic and anisotropic nanocomposites were prepared using the ion implantation technique. Their optical properties were studied at several wavelengths in the optical range 300–800 nm, across their plasmon resonances. The linear regime was characterized by measuring the absorption spectrum and the third-order nonlinear regime by means of the Z-scan technique using a tunable picosecond pulsed laser system (26 ps). Open-aperture Z-scan traces show a superposition of different optical nonlinear absorption (NLA) processes in the whole range studied. We associate these phenomena with the excitation of inter- and intra-band electronic transitions, which contribute with a positive sign to NLA, and to the formation of hot-electrons, which contribute with opposite sign to NLA. Closed-aperture traces for measuring nonlinear refraction (NLR) show different signs for Au and Ag samples, and a change of sign in Au is found when purely inter-band transitions are excited. In this work, for the appropriate wavelength, it is worth remarking on the free-electron response to the exciting light and its strong contribution to the nonlinear optical properties for low (intra-band) and high (hot-electrons) irradiances. (paper)
Stochastic, real-space, imaginary-time evaluation of third-order Feynman–Goldstone diagrams
International Nuclear Information System (INIS)
Willow, Soohaeng Yoo; Hirata, So
2014-01-01
A new, alternative set of interpretation rules of Feynman–Goldstone diagrams for many-body perturbation theory is proposed, which translates diagrams into algebraic expressions suitable for direct Monte Carlo integrations. A vertex of a diagram is associated with a Coulomb interaction (rather than a two-electron integral) and an edge with the trace of a Green's function in real space and imaginary time. With these, 12 diagrams of third-order many-body perturbation (MP3) theory are converted into 20-dimensional integrals, which are then evaluated by a Monte Carlo method. It uses redundant walkers for convergence acceleration and a weight function for importance sampling in conjunction with the Metropolis algorithm. The resulting Monte Carlo MP3 method has low-rank polynomial size dependence of the operation cost, a negligible memory cost, and a naturally parallel computational kernel, while reproducing the correct correlation energies of small molecules within a few mE h after 10 6 Monte Carlo steps
Stochastic, real-space, imaginary-time evaluation of third-order Feynman–Goldstone diagrams
Energy Technology Data Exchange (ETDEWEB)
Willow, Soohaeng Yoo [Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801 (United States); Center for Superfunctional Materials, Department of Chemistry, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784 (Korea, Republic of); Hirata, So, E-mail: sohirata@illinois.edu [Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801 (United States); CREST, Japan Science and Technology Agency, Saitama 332-0012 (Japan)
2014-01-14
A new, alternative set of interpretation rules of Feynman–Goldstone diagrams for many-body perturbation theory is proposed, which translates diagrams into algebraic expressions suitable for direct Monte Carlo integrations. A vertex of a diagram is associated with a Coulomb interaction (rather than a two-electron integral) and an edge with the trace of a Green's function in real space and imaginary time. With these, 12 diagrams of third-order many-body perturbation (MP3) theory are converted into 20-dimensional integrals, which are then evaluated by a Monte Carlo method. It uses redundant walkers for convergence acceleration and a weight function for importance sampling in conjunction with the Metropolis algorithm. The resulting Monte Carlo MP3 method has low-rank polynomial size dependence of the operation cost, a negligible memory cost, and a naturally parallel computational kernel, while reproducing the correct correlation energies of small molecules within a few mE{sub h} after 10{sup 6} Monte Carlo steps.
A third-order class-D amplifier with and without ripple compensation
Cox, Stephen M.; du Toit Mouton, H.
2018-06-01
We analyse the nonlinear behaviour of a third-order class-D amplifier, and demonstrate the remarkable effectiveness of the recently introduced ripple compensation (RC) technique in reducing the audio distortion of the device. The amplifier converts an input audio signal to a high-frequency train of rectangular pulses, whose widths are modulated according to the input signal (pulse-width modulation) and employs negative feedback. After determining the steady-state operating point for constant input and calculating its stability, we derive a small-signal model (SSM), which yields in closed form the transfer function relating (infinitesimal) input and output disturbances. This SSM shows how the RC technique is able to linearise the small-signal response of the device. We extend this SSM through a fully nonlinear perturbation calculation of the dynamics of the amplifier, based on the disparity in time scales between the pulse train and the audio signal. We obtain the nonlinear response of the amplifier to a general audio signal, avoiding the linearisation inherent in the SSM; we thereby more precisely quantify the reduction in distortion achieved through RC. Finally, simulations corroborate our theoretical predictions and illustrate the dramatic deterioration in performance that occurs when the amplifier is operated in an unstable regime. The perturbation calculation is rather general, and may be adapted to quantify the way in which other nonlinear negative-feedback pulse-modulated devices track a time-varying input signal that slowly modulates the system parameters.
Capmany, J; Gasulla, Ivana
2007-08-20
Although a considerable number of multimode fiber (MMF) links operate in a wavelength region around 850 nm where chromatic dispersion of a given modal group mu is described adequately by the second derivative beta(mu) (2) of the propagation constant beta(mu)(omega), there is also an increasing interest in MMF links transmitting in the second spectral window (@1300nm) where this second derivative vanishes being thus necessary to consider the third derivative beta(mu) (3) in the evaluation of the transfer function of the multimode fiber link. We present in this paper, for the first time to our knowledge, an analytical model for the transfer function of a multimode fiber (MMF) optic link taken into account the impact of third-order dispersion. The model extends the operation of a previously reported one for second-order dispersion. Our results show that the performance of broadband radio over fiber transmission through middle-reach distances can be improved by working at the minimum-dispersion wavelength as long as low-linewidth lasers are employed.
Third-order optical nonlinearity of N-doped graphene oxide nanocomposites at different GO ratios
Kimiagar, Salimeh; Abrinaei, Fahimeh
2018-05-01
In the present work, the influence of GO ratios on the structural, linear and nonlinear optical properties of nitrogen-doped graphene oxide nanocomposites (N-GO NCs) has been studied. N-GO NCs were synthesized by hydrothermal method. The XRD, FTIR, SEM, and TEM results confirmed the reduction of GO by nitrogen doping. The energy band gaps of N-GO NCs calculated from UV-Vis analyzed by using Tauc plot. To obtain further insight into potential optical changes in the N-GO NCs by increasing GO contents, Z-scan analysis was performed with nanosecond Nd-YAG laser at 532 nm. The nonlinear absorption coefficient, β, and nonlinear refractive index, n2, for N-GO NCs at the laser intensity of 113 MW/cm were measured and an increase was observed in both parameters after addition of nitrogen to GO. The third-order nonlinear optical susceptibilities of N-GO NCs were measured in the order of 10-9 esu. The results showed that N-GO NCs have negative nonlinearity which can be controlled by GO contents to obtain the highest values for nonlinear optical parameters. The nonlinear optical results not only imply that N-GO NCs can serve as an important material in the advancing of optoelectronics but also open new possibilities for the design of new graphene-based materials by variation of N and GO ratios as well as manufacturing conditions.
The Effects of Age on Short-Term Memory Loss due to Proactive Interference
Directory of Open Access Journals (Sweden)
Alisha Berkauzer
2011-01-01
Full Text Available This project focused on how proactive interference affects the short-term memory of people based on their age. The goal was to find the prime age for learning information and storing it in one's memory. Seven people from ages fifteen to forty were tested individually, using a set color pattern, in order to see how well each individual could remember the different color patterns as difficulty of the pattern increased. The obtained data was fitted by the polynomial regression. The “fitted” curve shows that as age increases, the individual's performance in memorizing the more difficult patterns decreases. Also, the peaked level of memory performance was found to be 24 for our experimental data.
TMS-induced neural noise in sensory cortex interferes with short-term memory storage
Directory of Open Access Journals (Sweden)
Tyler D Bancroft
2014-03-01
Full Text Available In a previous study, Harris et al. (2002 found disruption of vibrotactile short-term memory after applying single-pulse transcranial magnetic stimulation to primary somatosensory cortex (SI early in the maintenance period, and suggested that this demonstrated a role for SI in vibrotactile memory storage. While such a role is compatible with recent suggestions that sensory cortex is the storage substrate for working memory, it stands in contrast to a relatively large body of evidence from human EEG and single-cell recording in primates that instead points to prefrontal cortex as the storage substrate for vibrotactile memory. In the present study, we use computational methods to demonstrate how Harris et al.’s results can be reproduced by TMS-induced activity in sensory cortex and subsequent feedforward interference with memory traces stored in prefrontal cortex, thereby reconciling discordant findings in the tactile memory literature.
Short-term memory loss over time without retroactive stimulus interference.
Cowan, Nelson; AuBuchon, Angela M
2008-02-01
A key question in cognitive psychology is whether information in short-term memory is lost as a function of time. Lewandowsky, Duncan, and Brown (2004) argued against that memory loss because forgetting in serial recall occurred to the same extent across serial positions regardless of the rate of recall. However, we believe Lewandowsky et al. (2004) only prevented one of two types of rehearsal; they did not prevent nonarticulatory rehearsal via attention. To prevent articulatory and nonarticulatory rehearsal without introducing interference, we presented unevenly timed stimuli for serial recall and, on some trials, required that the timing of stimuli be reproduced in the response. In those trials only, evidence of memory loss over time emerged. Further research is needed to identify whether this memory loss is decay or lost distinctiveness.
A third-order gas-kinetic CPR method for the Euler and Navier-Stokes equations on triangular meshes
Zhang, Chao; Li, Qibing; Fu, Song; Wang, Z. J.
2018-06-01
A third-order accurate gas-kinetic scheme based on the correction procedure via reconstruction (CPR) framework is developed for the Euler and Navier-Stokes equations on triangular meshes. The scheme combines the accuracy and efficiency of the CPR formulation with the multidimensional characteristics and robustness of the gas-kinetic flux solver. Comparing with high-order finite volume gas-kinetic methods, the current scheme is more compact and efficient by avoiding wide stencils on unstructured meshes. Unlike the traditional CPR method where the inviscid and viscous terms are treated differently, the inviscid and viscous fluxes in the current scheme are coupled and computed uniformly through the kinetic evolution model. In addition, the present scheme adopts a fully coupled spatial and temporal gas distribution function for the flux evaluation, achieving high-order accuracy in both space and time within a single step. Numerical tests with a wide range of flow problems, from nearly incompressible to supersonic flows with strong shocks, for both inviscid and viscous problems, demonstrate the high accuracy and efficiency of the present scheme.
Oberauer, Klaus; Awh, Edward; Sutterer, David W.
2017-01-01
We report 4 experiments examining whether associations in visual working memory are subject to proactive interference from long-term memory (LTM). Following a long-term learning phase in which participants learned the colors of 120 unique objects, a working memory (WM) test was administered in which participants recalled the precise colors of 3…
International Nuclear Information System (INIS)
Jin Yi; Xie Qubing; Li Shiyuan
2003-01-01
Large N c approximation is adopted in popular e + e - event generators where the production probability of singlet chain states is 100% and that of color separate states is 0. In the real world N c =3, we investigate the origin and character of color and kinematics aspects in interference terms. We find that the production probability of color singlet chain states decreases from 83%, 77% to 67%, 58% for qq-bar + 2g and qq-bar + 3g system respectively after considering the interference terms. Especially, the production probability of color separate states increases to twice of that without interference terms for qq-bar + 2g. Hence when n is larger, we can expect that the production probability of singlet chain states will be far less than 1 and that of color separate states will significantly increase when n is larger
Long-term interference at the semantic level: Evidence from blocked-cyclic picture matching.
Wei, Tao; Schnur, Tatiana T
2016-01-01
Processing semantically related stimuli creates interference across various domains of cognition, including language and memory. In this study, we identify the locus and mechanism of interference when retrieving meanings associated with words and pictures. Subjects matched a probe stimulus (e.g., cat) to its associated target picture (e.g., yarn) from an array of unrelated pictures. Across trials, probes were either semantically related or unrelated. To test the locus of interference, we presented probes as either words or pictures. If semantic interference occurs at the stage common to both tasks, that is, access to semantic representations, then interference should occur in both probe presentation modalities. Results showed clear semantic interference effects independent of presentation modality and lexical frequency, confirming a semantic locus of interference in comprehension. To test the mechanism of interference, we repeated trials across 4 presentation cycles and manipulated the number of unrelated intervening trials (zero vs. two). We found that semantic interference was additive across cycles and survived 2 intervening trials, demonstrating interference to be long-lasting as opposed to short-lived. However, interference was smaller with zero versus 2 intervening trials, which we interpret to suggest that short-lived facilitation counteracted the long-lived interference. We propose that retrieving meanings associated with words/pictures from the same semantic category yields both interference due to long-lasting changes in connection strength between semantic representations (i.e., incremental learning) and facilitation caused by short-lived residual activation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Koh, Ming Teng; Thiele, Todd E; Bernstein, Ilene L
2002-12-01
The present experiments examined whether inhibition of cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) activity interferes with conditioned taste aversion (CTA) memories. Rats were centrally infused with the selective PKA inhibitor Rp-adenosine 3',5'-cyclic monophosphothioate triethylamine (Rp-cAMPS) before conditioning. Direct infusions of Rp-cAMPS into the amygdala showed no interference with short-term memory but did show significant attenuation of long-term memory and more rapid extinction. Results suggest that PKA activity is involved in the consolidation of long-term memory of CTAs, and that the amygdala may be 1 site that is important for this activity.
Baev, Alexander; Autschbach, Jochen; Boyd, Robert W; Prasad, Paras N
2010-04-12
Herein, we develop a phenomenological model for microscopic cascading and substantiate it with ab initio calculations. It is shown that the concept of local microscopic cascading of a second-order nonlinearity can lead to a third-order nonlinearity, without introducing any new loss mechanisms that could limit the usefulness of our approach. This approach provides a new molecular design protocol, in which the current great successes achieved in producing molecules with extremely large second-order nonlinearity can be used in a supra molecular organization in a preferred orientation to generate very large third-order response magnitudes. The results of density functional calculations for a well-known second-order molecule, (para)nitroaniline, show that a head-to-tail dimer configuration exhibits enhanced third-order nonlinearity, in agreement with the phenomenological model which suggests that such an arrangement will produce cascading due to local field effects.
Long-Term Interference at the Semantic Level: Evidence from Blocked-Cyclic Picture Matching
Wei, Tao; Schnur, Tatiana T.
2016-01-01
Processing semantically related stimuli creates interference across various domains of cognition, including language and memory. In this study, we identify the locus and mechanism of interference when retrieving meanings associated with words and pictures. Subjects matched a probe stimulus (e.g., cat) to its associated target picture (e.g., yarn)…
Hughes, Robert W.; Marsh, John E.
2017-01-01
A functional, perceptual-motor, account of serial short-term memory (STM) is examined by investigating the way in which an irrelevant spoken sequence interferes with verbal serial recall. Even with visual list-presentation, verbal serial recall is particularly susceptible to disruption by irrelevant spoken stimuli that have the same identity…
A Kramers-Moyal approach to the analysis of third-order noise with applications in option valuation.
Popescu, Dan M; Lipan, Ovidiu
2015-01-01
We propose the use of the Kramers-Moyal expansion in the analysis of third-order noise. In particular, we show how the approach can be applied in the theoretical study of option valuation. Despite Pawula's theorem, which states that a truncated model may exhibit poor statistical properties, we show that for a third-order Kramers-Moyal truncation model of an option's and its underlier's price, important properties emerge: (i) the option price can be written in a closed analytical form that involves the Airy function, (ii) the price is a positive function for positive skewness in the distribution, (iii) for negative skewness, the price becomes negative only for price values that are close to zero. Moreover, using third-order noise in option valuation reveals additional properties: (iv) the inconsistencies between two popular option pricing approaches (using a "delta-hedged" portfolio and using an option replicating portfolio) that are otherwise equivalent up to the second moment, (v) the ability to develop a measure R of how accurately an option can be replicated by a mixture of the underlying stocks and cash, (vi) further limitations of second-order models revealed by introducing third-order noise.
DEFF Research Database (Denmark)
Fasano, Andrea; Rasmussen, Henrik K.
2017-01-01
A third order accurate, in time and space, finite element scheme for the numerical simulation of three- dimensional time-dependent flow of the molecular stress function type of fluids in a generalized formu- lation is presented. The scheme is an extension of the K-BKZ Lagrangian finite element me...
On the periodic orbits of the Third-order differential equation x ' ' '- x ' ' x'- x= F(x,x',x ' ')
Llibre, Jaume
2013-01-01
Agraïments: The second author is partially supported by CAPES/MECD-DGU 222/2010 Brazil and Spain In this paper we study the periodic orbits of the third-order differential equation x''' − µx'' + x' − µx = εF(x, x', x''), where ε is a small parameter and the function F is of class C2.
Nishimoto, Yoshio
2015-09-07
We develop a formalism for the calculation of excitation energies and excited state gradients for the self-consistent-charge density-functional tight-binding method with the third-order contributions of a Taylor series of the density functional theory energy with respect to the fluctuation of electron density (time-dependent density-functional tight-binding (TD-DFTB3)). The formulation of the excitation energy is based on the existing time-dependent density functional theory and the older TD-DFTB2 formulae. The analytical gradient is computed by solving Z-vector equations, and it requires one to calculate the third-order derivative of the total energy with respect to density matrix elements due to the inclusion of the third-order contributions. The comparison of adiabatic excitation energies for selected small and medium-size molecules using the TD-DFTB2 and TD-DFTB3 methods shows that the inclusion of the third-order contributions does not affect excitation energies significantly. A different set of parameters, which are optimized for DFTB3, slightly improves the prediction of adiabatic excitation energies statistically. The application of TD-DFTB for the prediction of absorption and fluorescence energies of cresyl violet demonstrates that TD-DFTB3 reproduced the experimental fluorescence energy quite well.
Directory of Open Access Journals (Sweden)
Youliang Fu
2016-01-01
Full Text Available This paper is concerned with the asymptotic properties of solutions to a third-order nonlinear neutral delay differential equation with distributed deviating arguments. Several new theorems are obtained which ensure that every solution to this equation either is oscillatory or tends to zero. Two illustrative examples are included.
Denche, M.; Marhoune, A. L.
2001-01-01
We study a mixed problem with integral boundary conditions for a third-order partial differential equation of mixed type. We prove the existence and uniqueness of the solution. The proof is based on two-sided a priori estimates and on the density of the range of the operator generated by the considered problem.
DEFF Research Database (Denmark)
Karpman, V.I.; Shagalov, A.G.; Juul Rasmussen, J.
2002-01-01
The behavior of steady quasisoliton solutions to the extended third-order nonlinear Schrodinger (NLS) equation is studied in two cases: (i) when the coefficients in the equation approach the Hirota conditions, and (ii) near the limit of the regular NLS equation. (C) 2002 Published by Elsevier...
Experimental occlusal interference induces long-term masticatory muscle hyperalgesia in rats.
Cao, Ye; Xie, Qiu-Fei; Li, Kai; Light, Alan R; Fu, Kai-Yuan
2009-08-01
Temporomandibular joint or related masticatory muscle pain represents the most common chronic orofacial pain condition. Patients frequently report this kind of pain after dental alterations in occlusion. However, lack of understanding of the mechanisms of occlusion-related temporomandibular joint and muscle pain prevents treating this problem successfully. To explore the relationship between improper occlusion (occlusal interference) and masticatory muscle pain, we created an occlusal interference animal model by directly bonding a crown to a maxillary molar to raise the masticating surface of the tooth in rats. We raised the occlusal surface to three different heights (0.2, 0.4, and 0.6mm), and for one month we quantitatively measured mechanical nociceptive thresholds of the temporal and masseter muscles on both sides. Results showed a stimulus-response relationship between the height of occlusal interference and muscle hyperalgesia. Removal of the crown 6 days after occlusal interference showed that the removal at this time could not terminate the 1 month duration of mechanical hyperalgesia in the masticatory muscles. Lastly, we systemically administered NMDA antagonist MK801 (0.2, 0.1, and 0.05 mg/kg) to the treated rats and found that MK801 dose dependently attenuated the occlusal interference-induced hyperalgesia. These findings suggest that occlusal interference is directly related to masticatory muscle pain, and that central sensitization mechanisms are involved in the maintenance of the occlusal interference-induced mechanical hyperalgesia.
Proactive Interference and Its Release in Short-Term Memory of Mildly Retarded Adolescents
Cody, William J.; Borkowski, John G.
1977-01-01
Release from proactive interference in mildly retarded adolescents due to taxonomic shifts and rest periods prior to the final, critical-word triad was investigated with 40 educable mentally handicapped persons 18 years old. (Author/MH)
Marini, Francesco; Scott, Jerry; Aron, Adam R; Ester, Edward F
2017-07-01
Visual short-term memory (VSTM) enables the representation of information in a readily accessible state. VSTM is typically conceptualized as a form of "active" storage that is resistant to interference or disruption, yet several recent studies have shown that under some circumstances task-irrelevant distractors may indeed disrupt performance. Here, we investigated how task-irrelevant visual distractors affected VSTM by asking whether distractors induce a general loss of remembered information or selectively interfere with memory representations. In a VSTM task, participants recalled the spatial location of a target visual stimulus after a delay in which distractors were presented on 75% of trials. Notably, the distractor's eccentricity always matched the eccentricity of the target, while in the critical conditions the distractor's angular position was shifted either clockwise or counterclockwise relative to the target. We then computed estimates of recall error for both eccentricity and polar angle. A general interference model would predict an effect of distractors on both polar angle and eccentricity errors, while a selective interference model would predict effects of distractors on angle but not on eccentricity errors. Results showed that for stimulus angle there was an increase in the magnitude and variability of recall errors. However, distractors had no effect on estimates of stimulus eccentricity. Our results suggest that distractors selectively interfere with VSTM for spatial locations.
Item-nonspecific proactive interference in monkeys' auditory short-term memory.
Bigelow, James; Poremba, Amy
2015-09-01
Recent studies using the delayed matching-to-sample (DMS) paradigm indicate that monkeys' auditory short-term memory (STM) is susceptible to proactive interference (PI). During the task, subjects must indicate whether sample and test sounds separated by a retention interval are identical (match) or not (nonmatch). If a nonmatching test stimulus also occurred on a previous trial, monkeys are more likely to incorrectly make a "match" response (item-specific PI). However, it is not known whether PI may be caused by sounds presented on prior trials that are similar, but nonidentical to the current test stimulus (item-nonspecific PI). This possibility was investigated in two experiments. In Experiment 1, memoranda for each trial comprised tones with a wide range of frequencies, thus minimizing item-specific PI and producing a range of frequency differences among nonidentical tones. In Experiment 2, memoranda were drawn from a set of eight artificial sounds that differed from each other by one, two, or three acoustic dimensions (frequency, spectral bandwidth, and temporal dynamics). Results from both experiments indicate that subjects committed more errors when previously-presented sounds were acoustically similar (though not identical) to the test stimulus of the current trial. Significant effects were produced only by stimuli from the immediately previous trial, suggesting that item-nonspecific PI is less perseverant than item-specific PI, which can extend across noncontiguous trials. Our results contribute to existing human and animal STM literature reporting item-nonspecific PI caused by perceptual similarity among memoranda. Together, these observations underscore the significance of both temporal and discriminability factors in monkeys' STM. Copyright © 2015 Elsevier B.V. All rights reserved.
Elamien, Mohamed B.; Mahmoud, Soliman A.
2018-03-01
In this paper, a third-order elliptic lowpass filter is designed using highly linear digital programmable balanced OTA. The filter exhibits a cutoff frequency tuning range from 2.2 MHz to 7.1 MHz, thus, it covers W-CDMA, UMTS, and DVB-H standards. The programmability concept in the filter is achieved by using digitally programmable operational transconductors amplifier (DPOTA). The DPOTA employs three linearization techniques which are the source degeneration, double differential pair and the adaptive biasing. Two current division networks (CDNs) are used to control the value of the transconductance. For the DPOTA, the third-order harmonic distortion (HD3) remains below -65 dB up to 0.4 V differential input voltage at 1.2 V supply voltage. The DPOTA and the filter are designed and simulated in 90 nm CMOS technology with LTspice simulator.
Thangaraj, M.; Vinitha, G.; Sabari Girisun, T. C.; Anandan, P.; Ravi, G.
2015-10-01
Optical nonlinearity of metal complexes of p-nitrophenolate (M=Li, Na and K) in ethanol is studied by using a continuous wave (cw) diode pumped Nd:YAG laser (532 nm, 50 mW). The predominant mechanism of observed nonlinearity is thermal in origin. The nonlinear refractive index and the nonlinear absorption coefficient of the samples were found to be in the order of 10-8 cm2/W and 10-3 cm/W respectively. Magnitude of third-order optical parameters varies according to the choice of alkali metal chosen for metal complex formation of p-nitrophenolate. The third-order nonlinear susceptibility was found to be in the order of 10-6 esu. The observed saturable absorption and the self-defocusing effect were used to demonstrate the optical limiting action at 532 nm by using the same cw laser beam.
International Nuclear Information System (INIS)
Mordik, S.N.; Ponomarev, A.G.
2001-01-01
To study nonlinear dynamics of charged particles in magnetic sector analyzers one applied the matriciant method. When calculating matriciants (transfer matrices) one took account of the boundary-value effects associated with the effect of scattering field, as well as, the higher harmonics of the sector magnetic field up to the third order inclusive. In case of the rectangular distribution of field components along the optical axis one obtained analytical expressions for all aberration coefficients up to the third order exclusive. To simulate the real field with the width of scattering field not equal to zero one applied smooth distribution of components for which calculation of similar aberration coefficients was conducted using the conservative numerical method [ru
Seino, Junji; Kageyama, Ryo; Fujinami, Mikito; Ikabata, Yasuhiro; Nakai, Hiromi
2018-06-01
A semi-local kinetic energy density functional (KEDF) was constructed based on machine learning (ML). The present scheme adopts electron densities and their gradients up to third-order as the explanatory variables for ML and the Kohn-Sham (KS) kinetic energy density as the response variable in atoms and molecules. Numerical assessments of the present scheme were performed in atomic and molecular systems, including first- and second-period elements. The results of 37 conventional KEDFs with explicit formulae were also compared with those of the ML KEDF with an implicit formula. The inclusion of the higher order gradients reduces the deviation of the total kinetic energies from the KS calculations in a stepwise manner. Furthermore, our scheme with the third-order gradient resulted in the closest kinetic energies to the KS calculations out of the presented functionals.
International Nuclear Information System (INIS)
Afuwape, A.U.; Omari, P.
1987-11-01
This paper deals with the solvability of the nonlinear operator equations in normed spaces Lx=EGx+f, where L is a linear map with possible nontrivial kernel. Applications are given to the existence of periodic solutions for the third order scalar differential equation x'''+ax''+bx'+cx+g(t,x)=p(t), under various conditions on the interaction of g(t,x)/x with spectral configurations of a, b and c. (author). 48 refs
Energy Technology Data Exchange (ETDEWEB)
Tan, Min; Liu, Qiming, E-mail: qmliu@whu.edu.cn [Wuhan University, Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology (China)
2016-12-15
Taking advantage of the channel confinement of mesoporous films to prevent the agglomeration of Ag nanoparticles to achieve large third-order optical nonlinearity in amorphous materials, Ag-loaded composite mesoporous silica film was prepared by the electrochemical deposition method on ITO substrate. Ag ions were firstly transported into the channels of mesoporous film by the diffusion and binding force of channels, which were reduced to nanoparticles by applying suitable voltage. The existence and uniform distribution of Ag nanoparticles ranging in 1–10 nm in the mesoporous silica thin films were exhibited by UV spectrophotometer, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) measurements. The third-order optical nonlinearity induced by Ag nanoparticles was studied by the Z-scan technique. Due to the local field surface plasmon resonance, the maximum third-order nonlinear optical susceptibility of Ag-loaded composite mesoporous silica film is 1.53×10{sup −10} esu, which is 1000 times larger than that of the Ag-contained chalcogenide glasses which showed large nonlinearity in amorphous materials.
Green synthesis and third-order nonlinear optical properties of 6-(9H-carbazol-9-yl) hexyl acetate
Chen, Baili; Geng, Feng; Luo, Xuan; Zhong, Quanjie; Zhang, Qingjun; Fang, Yu; Huang, Chuanqun; Yang, Ruizhuang; Shao, Ting; Chen, Shufan
2016-10-01
An extremely simple and green approach for the synthesis of photoelectric material 6-(9H-carbazol-9-yl) hexy-acetate (CHA) has been described in detail. The molecular structure of CHA was identified with Fourier transform infrared (FT-IR) spectra and 1H Nuclear Magnetic Resonance (1H NMR) spectroscopy. The optical absorption of CHA was recorded using ultraviolet-visible (UV-vis) spectrum. Notably, the reaction was accomplished in water medium instead of traditional toxic solvents (e.g., benzene and chloroform). The yield of CHA is up to 99%, which is increased by 13% compared with the traditional method. The approach developed by us makes it possible to achieve commercial production of CHA. Moreover, the thermal stability of CHA was studied with thermogravimetric (TG) and derivative thermogravimetric (DTG) method. The third-order nonlinear optical (NLO) properties of CHAn (obtained by new method) and CHAt (obtained by traditional method) have been studied by a Z-scan technique at 440 nm. The thermal decomposition temperature is above 200 °C. The third-order NLO of CHAn and CHAt are the same. The third-order NLO susceptibility χ (3) and two photon Figures of Merit (FOMs) of CHA are 1.58 × 10-8 (esu) and 4.55, respectively. The results reveal that CHA may be a promising candidate for all-optical switching application.
Third-order nonlinear optical properties of GeSe2-Ga2Se3-PbI2 glasses
International Nuclear Information System (INIS)
Tang Gao; Liu Cunming; Luo Lan; Chen Wei
2010-01-01
The third-order nonlinear optical (NLO) properties of new selenium-based GeSe 2 -Ga 2 Se 3 -PbI 2 glasses have been measured using the optical Kerr effect (OKE) technique, with picosecond and femtosecond laser pulses. The 0.70GeSe 2 -0.15Ga 2 Se 3 -0.15PbI 2 glass has the largest third-order optical nonlinear susceptibility in GeSe 2 -Ga 2 Se 3 -PbI 2 glass system with χ (3) of 5.28x10 12 esu. In addition, the response time of glasses is sub-picosecond, which is predominantly associated with electron cloud. Local structure of the glasses has been identified by using Raman studies, while the origins of the observed nonlinear optical response are discussed. The [Ge(Ga)Se 4 ] tetrahedral and lone-pair electrons from highly polarizable Pb atom in glasses play an important role in enhanced NLO response. These results as well as their good chemical stability indicate that GeSe 2 -Ga 2 Se 3 -PbI 2 glasses are promising materials for photonic applications of third-order nonlinear optical signal processing.
Hughes, Robert W; Marsh, John E
2017-04-01
A functional, perceptual-motor, account of serial short-term memory (STM) is examined by investigating the way in which an irrelevant spoken sequence interferes with verbal serial recall. Even with visual list-presentation, verbal serial recall is particularly susceptible to disruption by irrelevant spoken stimuli that have the same identity as-but that are order-incongruent with-the to-be-remembered items. We test the view that such interference is because of the obligatory perceptual organization of the spoken stimuli yielding a sequence that competes with a subvocal motor-plan assembled to support the reproduction of the to-be-remembered list. In support of this view, the interference can be eliminated without changing either the identities or objective serial order of the spoken stimuli but merely by promoting a subjective perceptual organization that strips them of their order-incongruent relation to the to-be-remembered list (Experiment 1). The interference is also eliminated if subvocal motor sequence-planning is impeded via articulatory suppression (Experiment 2). The results are in line with the view that performance-limits in verbal serial STM are because of having to exploit perceptual and motor processes for purposes for which they did not evolve, not the inherently limited capacity of structures or mechanisms dedicated to storage. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Directory of Open Access Journals (Sweden)
Maryam Hayati
2010-04-01
Full Text Available Objective: With increased recognition of the importance of conscious process and cognition activities in the stability and regulation of posture and also in line of probable adaptation in central nervous system in patients with functional ankle instability, this study was aimed to assess interference patterns between short–term memory task and postural stability tasks in functional ankle instability patients in comparison with healthy individuals. Materials & Methods: In this cross–sectional and case–control study, with dual–task paradigm fifteen functional ankle instability patients whom were selected simply and conveniently and fifteen healthy persons whom were matched with patients as control group were assessed and compared. Six steps of tests were performed for every case with two situation of balance Biodex system instability and three situation of auditory short–term memory task. Data were analyzed by repeated measurement ANOVA. Results: Finding showed that there was significant interference between postural task and cognitive task in both groups (P<0.05 , but there was no significant difference between interferences of two groups. Conclusion: Present study, certificated disruption in information processing in a peripheral musculoskeletal injury such as functional ankle instability. Application of training programs in order to facilitate central information processing in balance rehabilitation process of this patients and improved dual–task paradigms with different degrees of cognitive and postural tasks seems to be effective.
A third-order moving mesh cell-centered scheme for one-dimensional elastic-plastic flows
Cheng, Jun-Bo; Huang, Weizhang; Jiang, Song; Tian, Baolin
2017-11-01
A third-order moving mesh cell-centered scheme without the remapping of physical variables is developed for the numerical solution of one-dimensional elastic-plastic flows with the Mie-Grüneisen equation of state, the Wilkins constitutive model, and the von Mises yielding criterion. The scheme combines the Lagrangian method with the MMPDE moving mesh method and adaptively moves the mesh to better resolve shock and other types of waves while preventing the mesh from crossing and tangling. It can be viewed as a direct arbitrarily Lagrangian-Eulerian method but can also be degenerated to a purely Lagrangian scheme. It treats the relative velocity of the fluid with respect to the mesh as constant in time between time steps, which allows high-order approximation of free boundaries. A time dependent scaling is used in the monitor function to avoid possible sudden movement of the mesh points due to the creation or diminishing of shock and rarefaction waves or the steepening of those waves. A two-rarefaction Riemann solver with elastic waves is employed to compute the Godunov values of the density, pressure, velocity, and deviatoric stress at cell interfaces. Numerical results are presented for three examples. The third-order convergence of the scheme and its ability to concentrate mesh points around shock and elastic rarefaction waves are demonstrated. The obtained numerical results are in good agreement with those in literature. The new scheme is also shown to be more accurate in resolving shock and rarefaction waves than an existing third-order cell-centered Lagrangian scheme.
Pigeon, J. J.; Tochitsky, S. Ya.; Welch, E. C.; Joshi, C.
2018-04-01
We present measurements of the third-order optical nonlinearity of Kr, Xe, N2, O2, and air at a wavelength near 10 µm by using four-wave mixing of ˜15 -GW /c m2 , 200-ps (full width at half maximum) C O2 laser pulses. Measurements in molecular gases resulted in an asymmetric four-wave mixing spectrum indicating that the nonlinear response is strongly affected by the delayed, rotational contribution to the effective nonlinear refractive index. Within the uncertainty of our measurements, we have found that the long-wavelength nonlinear refractive indices of these gases are consistent with measurements performed in the near IR.
Third-Order Density Perturbation and One-Loop Power Spectrum in Dark-Energy-Dominated Universe
Takahashi, Ryuichi
2008-01-01
We investigate the third-order density perturbation and the one-loop correction to the linear power spectrum in the dark-energy cosmological model. Our main interest is to understand the dark-energy effect on baryon acoustic oscillations in a quasi-nonlinear regime ($k \\approx 0.1h$/Mpc). Analytical solutions and simple fitting formulae are presented for the dark-energy model with the general time-varying equation of state $w(a)$. It turns out that the power spectrum coincides with the approx...
Alduais, Ahmed Mohammed Saleh; Almukhaizeem, Yasir Saad
2015-01-01
Purpose: To see if there is a correlation between interference and short-term memory recall and to examine interference as a factor affecting memory recalling of Arabic and abstract words through free, cued, and serial recall tasks. Method: Four groups of undergraduates in King Saud University, Saudi Arabia participated in this study. The first…
Priyadharshini, A.; Kalainathan, S.
2018-04-01
2-(4-fluorobenzylidene) malononitrile (FBM), an organic third order nonlinear (TONLO) single crystal with the dimensions of 32 × 7 × 11 mm3, has been successfully grown in acetone solution by slow evaporation technique at 35 °C. The crystal system (triclinic), space group (P-1) and crystalline purity of the titular crystal were measured by single crystal and powder X-ray diffraction, respectively. The molecular weight and the multiple functional groups of the FBM material were confirmed through the mass and FT-IR spectral analysis. UV-Vis-NIR spectral study enroles that the FBM crystal exhibits excellent transparency (83%) in the entire visible and near infra-red region with a wide bandgap 2.90 eV. The low dielectric constant (εr) value of FBM crystal is appreciable for microelectronics industry applications. Thermal stability and melting point (130.09 °C) were ascertained by TGA-DSC analysis. The laser-induced surface damage threshold (LDT) value of FBM specimen is found to be 2.14 GW/cm2, it is fairly good compared to other reported NLO crystals. The third - order nonlinear optical character of the FBM crystal was confirmed through the typical single beam Z-scan technique. All these finding authorized that the organic crystal of FBM is favorably suitable for NLO applications.
Directory of Open Access Journals (Sweden)
T. William Bentley
2015-05-01
Full Text Available Hydrolyses of acid derivatives (e.g., carboxylic acid chlorides and fluorides, fluoro- and chloroformates, sulfonyl chlorides, phosphorochloridates, anhydrides exhibit pseudo-first order kinetics. Reaction mechanisms vary from those involving a cationic intermediate (SN1 to concerted SN2 processes, and further to third order reactions, in which one solvent molecule acts as the attacking nucleophile and a second molecule acts as a general base catalyst. A unified framework is discussed, in which there are two reaction channels—an SN1-SN2 spectrum and an SN2-SN3 spectrum. Third order rate constants (k3 are calculated for solvolytic reactions in a wide range of compositions of acetone-water mixtures, and are shown to be either approximately constant or correlated with the Grunwald-Winstein Y parameter. These data and kinetic solvent isotope effects, provide the experimental evidence for the SN2-SN3 spectrum (e.g., for chloro- and fluoroformates, chloroacetyl chloride, p-nitrobenzoyl p-toluenesulfonate, sulfonyl chlorides. Deviations from linearity lead to U- or V-shaped plots, which assist in the identification of the point at which the reaction channel changes from SN2-SN3 to SN1-SN2 (e.g., for benzoyl chloride.
International Nuclear Information System (INIS)
Kobayashi, Takashi; Shinke, Wataru; Nagase, Takashi; Murakami, Shuichi; Naito, Hiroyoshi
2014-01-01
We examined the enhancements in the third-order optical susceptibility (χ (3) ) of spin-coated thin films of poly(3-hexylthiophene) using an anhydrous solvent with a high boiling point. The χ (3) value was found to be enhanced as the boiling point of the solvent increased. In this study, the largest value of χ (3) was obtained for thin films that were spin-coated in an inert atmosphere using anhydrous dichlorobenzene and then was subsequently exposed to its vapor for 1 h. The maximum value of the imaginary part of χ (3) was determined to be 1.8 × 10 -9 esu, which is more than three times greater than that of thin films spin-coated in an ambient atmosphere using a solvent with a low boiling point, such as chloroform. - Highlights: • Enhancements in nonlinear optical properties of a conjugated polymer were examined. • Thin films were fabricated by spin-coating using a solvent with a high boiling point. • The third-order optical susceptibility increased with increasing boiling point. • An additional enhancement was obtained by the vapor-treatment technique. • These thin films were sufficiently homogeneous for use in nonlinear optical devices
International Nuclear Information System (INIS)
Shihong Ma; Liying Liu; Xingze Lu
1995-01-01
Third-order nonlinear susceptibilities χ xxxx (3) (-3ω; ω, ω, ω) have been deduced by measuring third-harmonic generation in Langmuir-Blodgett (LB) films of 1-benzyl-9-hydrofullerene-60 (C 60 -Be). The structural features of the condensed layer at the air-water interface and LB films of the C 60 -Be were investigated by small angle x-ray diffraction (SAXD) and optical measurements. The third-order nonlinear susceptibilities (χ (3) ) were obtained by measuring the THG intensities in LB films of C 60 -Be and comparing with that of CS 2 used as the reference. The value of χ xxxx (3) (2.1 x 10 -11 esu) was deduced at a 65 nm thick films. The χ (3) is attributed to a three-photon near resonance at the energy level of 29410 cm -1 . A new-type of two-chain amphiphilic molecule 1,10-bistearyl-4,6,13, 15-tetra-18-nitrogencrown-6 (NC) was used as insert material to construct mixed C 60 -Be/NC LB films. Our π-A, UV-visible absorption and SAXD measurements showed that the structural improvement in the mixed C 60 -Be/NC LB films was realized by insertion of the C 60 -Be molecules between the two hydrophobic chains of the NC molecules
Energy Technology Data Exchange (ETDEWEB)
Sivakumar, B.; Mohan, R. [Preidency College, Bangalore (India); Raj, S. Gokul [RR and Dr. SR Technical Univ., Avadi (India); Kumar, G. Ramesh [Anna Univ., Arni (India)
2012-11-15
Single crystals of lithium potassium phthalate (LiKP) were successfully grown from aqueous solution by solvent evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction. The lithium potassium phthalate C{sub 16} H{sub 12} K Li{sub 3} O{sub 11} belongs to triclinic system with the following unit-cell dimensions at 298(2) K; a = 7.405(5) A; b = 9.878(5) A; c = 13.396(5) A; α = 71.778(5) .deg.; β = 87.300(5) .deg.; γ = 85.405(5) .deg.; having a space group P1. Mass spectrometric analysis provides the molecular weight of the compound and possible ways of fragmentations occurs in the compound. Thermal stability of the crystal was also studied by both simultaneous TGA/DTA analyses. The UV-Vis-NIR spectrum shows a good transparency in the whole of Visible and as well as in the near IR range. Third order nonlinear optical studies have also been studied by Z-scan technique. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated.
Nobuhara, Hirofumi; Okamoto, Yoshihiro; Yamashita, Masato; Nakamura, Yasuaki; Osawa, Hisashi; Muraoka, Hiroaki
2014-05-01
In this paper, we investigate the influence of the writing and reading intertrack interferences (ITIs) in terms of bit aspect ratio (BAR) in shingled magnetic recording by computer simulation using a read/write model which consists of a writing process based on Stoner-Wohlfarth switching asteroid by a one-side shielded isosceles triangular write head and a reading process by an around shielded read head for a discrete Voronoi medium model. The results show that BAR should be 3 to reduce the influence of writing and reading ITIs, media noise, and additive white Gaussian noise in an assumed areal density of 4.61Tbpsi.
Near resonant and nonresonant third-order optical nonlinearities of colloidal InP/ZnS quantum dots
Wang, Y.; Yang, X.; He, T. C.; Gao, Y.; Demir, H. V.; Sun, X. W.; Sun, H. D.
2013-01-01
We have investigated the third-order optical nonlinearities of high-quality colloidal InP/ZnS core-shell quantum dots (QDs) using Z-scan technique with femtosecond pulses. The two-photon absorption cross-sections as high as 6.2 × 103 GM are observed at 800 nm (non-resonant regime) in InP/ZnS QDs with diameter of 2.8 nm, which is even larger than those of CdSe, CdS, and CdTe QDs at similar sizes. Furthermore, both of the 2.2 nm and 2.8 nm-sized InP/ZnS QDs exhibit strong saturable absorption in near resonant regime, which is attributed to large exciton Bohr radius in this material. These results strongly suggest the promising potential of InP/ZnS QDs for widespread applications, especially in two-photon excited bio-imaging and saturable absorbing.
Third-order spontaneous parametric down-conversion in thin optical fibers as a photon-triplet source
Energy Technology Data Exchange (ETDEWEB)
Corona, Maria [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, apdo. postal 70-543, DF 04510 Mexico City (Mexico); Departamento de Optica, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Apartado Postal 2732, BC 22860 Ensenada (Mexico); Garay-Palmett, Karina; U' Ren, Alfred B. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, apdo. postal 70-543, DF 04510 Mexico City (Mexico)
2011-09-15
We study the third-order spontaneous parametric down-conversion (TOSPDC) process, as a means to generate entangled photon triplets. Specifically, we consider thin optical fibers as the nonlinear medium to be used as the basis for TOSPDC in configurations where phase matching is attained through the use of more than one fiber transverse modes. Our analysis in this paper, which follows from our earlier paper [Opt. Lett. 36, 190-192 (2011)], aims to supply experimentalists with the details required in order to design a TOSPDC photon-triplet source. Specifically, our analysis focuses on the photon triplet state, on the rate of emission, and on the TOSPDC phase-matching characteristics for the cases of frequency-degenerate and frequency nondegenerate TOSPDC.
Behzadi, Kobra; Baghelani, Masoud
2014-05-01
This paper presents a third order continuous time current mode ΣΔ modulator for WLAN 802.11b standard applications. The proposed circuit utilized feedback architecture with scaled and optimized DAC coefficients. At circuit level, we propose a modified cascade current mirror integrator with reduced input impedance which results in more bandwidth and linearity and hence improves the dynamic range. Also, a very fast and precise novel dynamic latch based current comparator is introduced with low power consumption. This ultra fast comparator facilitates increasing the sampling rate toward GHz frequencies. The modulator exhibits dynamic range of more than 60 dB for 20 MHz signal bandwidth and OSR of 10 while consuming only 914 μW from 1.8 V power supply. The FoM of the modulator is calculated from two different methods, and excellent performance is achieved for proposed modulator.
Maidur, Shivaraj R.; Jahagirdar, Jitendra R.; Patil, Parutagouda Shankaragouda; Chia, Tze Shyang; Quah, Ching Kheng
2018-01-01
We report synthesis, characterizations, structure-property relationships, and third-order nonlinear optical studies for two new chalcone derivatives, (2E)-1-(anthracen-9-yl)-3-(4-bromophenyl)prop-2-en-1-one (Br-ANC) and (2E)-1-(anthracen-9-yl)-3-(4-chlorophenyl)prop-2-en-1-one (Cl-ANC). These derivatives were crystallized in the centrosymmetric monoclinic P21/c crystal structure. The intermolecular interactions of both the crystals were visualized by Hirshfeld surface analyses (HSA). The crystals are thermally stable up to their melting points (180.82 and 191.16 °C for Cl-ANC and Br-ANC, respectively). The geometry optimizations, FT-IR spectra, 1H and 13C NMR spectra, electronic absorption spectra, electronic transitions, and HOMO-LUMO energy gaps were studied by Density Functional Theory (DFT) at B3LYP/6-311+G(d, p) level. The theoretical results provide excellent agreement with experimental findings. The electric dipole moments, static polarizabilities, molecular electrostatic potentials (MEP) and global chemical reactivity descriptors (GCRD) were also theoretically computed. The materials exhibited good nonlinear absorption (NLA), nonlinear refraction (NLR) and optical limiting (OL) behavior under diode-pumped solid-state (DPSS) continuous wave (CW) laser excitation (532 nm and 200 mW). The NLO parameters such as NLA coefficient (β∼10-5 cmW-1), NLR index (n2∼10-10 cm2 W-1) and third-order NLO susceptibilities (χ(3) ∼10-7 esu) were measured. Further, we estimated one-photon and two-photon figures of merit, which satisfy the demands (W > 1 and T < 1) for all-optical switching. Thus, the present chalcone derivatives with anthracene moiety are potential materials for OL and optical switching applications.
Lodico, Dana M.; Torres, Rendell R.; Shimizu, Yasushi; Hunter, Claudia
2004-05-01
This study investigates the effects of interference speech and the built acoustical environment on human performance, and the possibility of designing spaces to architecturally meet the acoustical goals of office and classroom environments. The effects of room size, geometry, and acoustical parameters on human performance are studied through human subject testing. Three experiments are used to investigate the effects of distracting background speech on short-term memory for verbally presented prose under constrained laboratory conditions. Short-term memory performance is rated within four different acoustical spaces and five background noise levels, as well as a quiet condition. The presentation will cover research methods, results, and possibilities for furthering this research. [Work supported by the Program in Architectural Acoustics, School of Architecture, Rensselaer Polytechnic Institute.
Izsák, Róbert; Neese, Frank
2013-07-01
The 'chain of spheres' approximation, developed earlier for the efficient evaluation of the self-consistent field exchange term, is introduced here into the evaluation of the external exchange term of higher order correlation methods. Its performance is studied in the specific case of the spin-component-scaled third-order Møller--Plesset perturbation (SCS-MP3) theory. The results indicate that the approximation performs excellently in terms of both computer time and achievable accuracy. Significant speedups over a conventional method are obtained for larger systems and basis sets. Owing to this development, SCS-MP3 calculations on molecules of the size of penicillin (42 atoms) with a polarised triple-zeta basis set can be performed in ∼3 hours using 16 cores of an Intel Xeon E7-8837 processor with a 2.67 GHz clock speed, which represents a speedup by a factor of 8-9 compared to the previously most efficient algorithm. Thus, the increased accuracy offered by SCS-MP3 can now be explored for at least medium-sized molecules.
Levels of Interference in Long and Short-Term Memory Differentially Modulate Non-REM and REM Sleep.
Fraize, Nicolas; Carponcy, Julien; Joseph, Mickaël Antoine; Comte, Jean-Christophe; Luppi, Pierre-Hervé; Libourel, Paul-Antoine; Salin, Paul-Antoine; Malleret, Gaël; Parmentier, Régis
2016-12-01
It is commonly accepted that sleep is beneficial to memory processes, but it is still unclear if this benefit originates from improved memory consolidation or enhanced information processing. It has thus been proposed that sleep may also promote forgetting of undesirable and non-essential memories, a process required for optimization of cognitive resources. We tested the hypothesis that non-rapid eye movement sleep (NREMS) promotes forgetting of irrelevant information, more specifically when processing information in working memory (WM), while REM sleep (REMS) facilitates the consolidation of important information. We recorded sleep patterns of rats trained in a radial maze in three different tasks engaging either the long-term or short-term storage of information, as well as a gradual level of interference. We observed a transient increase in REMS amount on the day the animal learned the rule of a long-term/reference memory task (RM), and, in contrast, a positive correlation between the performance of rats trained in a WM task involving an important processing of interference and the amount of NREMS or slow wave activity. Various oscillatory events were also differentially modulated by the type of training involved. Notably, NREMS spindles and REMS rapid theta increase with RM training, while sharp-wave ripples increase with all types of training. These results suggest that REMS, but also rapid oscillations occurring during NREMS would be specifically implicated in the long-term memory in RM, whereas NREMS and slow oscillations could be involved in the forgetting of irrelevant information required for WM. © 2016 Associated Professional Sleep Societies, LLC.
Directory of Open Access Journals (Sweden)
naser jafarzadeh
2016-11-01
Full Text Available Introduction Growth analysis has been widely used in breeding programs to identify the important plant developmental phases and components related to higher yield under a particular set of environmental conditions. Castor bean (Ricinus communis L. is an important commercial crop. Castor oil based by products is used in manufacturing of several commercially important commodities like surfactants, coatings, greases, pharmaceuticals, cosmetics, polyesters, polymers, etc. Interference (Interactive effects among species on inter-species populations is one of the main issues on the eco-physiology of plant populations where weeds impose negative effects by approaching the plant to compete in light, water and nutrient elements availability and results in reduced growth and yield (Shinggu et al., 2011. Growth indices are useful for interpreting plant reactions to the crop and weed density. Various reasons have been attributed for the low productivity among the most important is weed competition (Radosevich, 1987. The aim of the present experiment was evaluating the interference effects of redroot pigweed on growth indices of castor bean in northwest of Iran. Materials and methods This experiment was conducted in Urmia, Iran (Agricultural Research of West Azarbayjan, Saatlo Station (37°44´18״ N Latitude and 45° 10´ 53״ E Longitude, at 1338 m above sea level in 2012. The soil of the experimental field was sandy - loam, with pH of 7.2. Competitive pattern of experiment was in two-factor based on a randomized complete block design (RCBD with three replications arranged in four castor plant densities (3, 4, 5 and 6 plants.m-2 and four redroot pigweed densities (0, 5, 10 and 15 plants.m-2. Redroot pigweed and castor seeds were simultaneously directly planted on the 22th May in 2012. Redroot pigweed plants were weeded at the times related to the treatments level. Irrigation and intercultural operations were performed whenever necessary. Plots were 3m×5m
International Nuclear Information System (INIS)
Vucic, S.; Potvliege, R.M.; Joachain, C.J.; Louvain Univ., Louvain-la-Neuve
1987-01-01
We study the elastic scattering of electrons by the metastable states H(2s), He(2 1 S) and He(2 3 S) at intermediate energies within the framework of the third-order optical potential theory. The first-, second- and third-order contributions to the optical potential are analysed separately, and are compared with the corresponding quantities for e - H(1s) and e - He(1 1 S) elastic scattering. Results for positron impact scattering are also presented. (author)
Short-term memory for auditory and visual durations: evidence for selective interference effects.
Rattat, Anne-Claire; Picard, Delphine
2012-01-01
The present study sought to determine the format in which visual, auditory and auditory-visual durations ranging from 400 to 600 ms are encoded and maintained in short-term memory, using suppression conditions. Participants compared two stimulus durations separated by an interval of 8 s. During this time, they performed either an articulatory suppression task, a visuospatial tracking task or no specific task at all (control condition). The results showed that the articulatory suppression task decreased recognition performance for auditory durations but not for visual or bimodal ones, whereas the visuospatial task decreased recognition performance for visual durations but not for auditory or bimodal ones. These findings support the modality-specific account of short-term memory for durations.
Short-Term Memory Loss Over Time Without Retroactive Stimulus Interference
Cowan, Nelson; AuBuchon, Angela M.
2008-01-01
A key question in cognitive psychology is whether information in short-term memory is lost as a function of time. Lewandowsky, Duncan, and Brown (2004) argued against that memory loss because forgetting in serial recall occurred to the same extent across serial positions regardless of the rate of recall. However, we believe Lewandowsky et al. only prevented one of two types of rehearsal; they did not prevent non-articulatory rehearsal via attention. To prevent articulatory and non-articulator...
Ahmed Mohammed Saleh Alduais; Yasir Saad Almukhaizeem
2015-01-01
Purpose: To see if there is a correlation between interference and short-term memory recall and to examine interference as a factor affecting memory recalling of Arabic and abstract words through free, cued, and serial recall tasks. Method: Four groups of undergraduates in King Saud University, Saudi Arabia participated in this study. The first group consisted of 9 undergraduates who were trained to perform three types of recall for 20 Arabic abstract and concrete words. The second, third and...
Bancroft, Tyler D; Hogeveen, Jeremy; Hockley, William E; Servos, Philip
2014-01-01
In a previous study, Harris et al. (2002) found disruption of vibrotactile short-term memory after applying single-pulse transcranial magnetic stimulation (TMS) to primary somatosensory cortex (SI) early in the maintenance period, and suggested that this demonstrated a role for SI in vibrotactile memory storage. While such a role is compatible with recent suggestions that sensory cortex is the storage substrate for working memory, it stands in contrast to a relatively large body of evidence from human EEG and single-cell recording in primates that instead points to prefrontal cortex as the storage substrate for vibrotactile memory. In the present study, we use computational methods to demonstrate how Harris et al.'s results can be reproduced by TMS-induced activity in sensory cortex and subsequent feedforward interference with memory traces stored in prefrontal cortex, thereby reconciling discordant findings in the tactile memory literature.
Energy Technology Data Exchange (ETDEWEB)
Palma, Daniel Artur Pinheiro [Centro Federal de Educacao Tecnologica de Quimica de Nilopolis, RJ (Brazil)]. E-mails: dpalma@cefeteq.br; Martinez, Aquilino Senra; Goncalves, Alessandro C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE). Programa de Engenharia Nuclear]. E-mail: agoncalves@con.ufrj.br; aquilino@lmp.ufrj.br
2008-07-01
The calculation of the Doppler broadening function and the interference term are very important in the generation of nuclear data. Recent papers have proposed analytical formulations for both functions and, despite their being simple and precise, they contain the error function with a complex argument. With the intention of simplifying the mathematical treatment two approximations are proposed in this paper. The first one consists of using an expansion in the form of series to treat the error function. The other approximation is based on simplifications in the differential equations that govern the Doppler broadening function. For validation purpose the result obtained is compared to the one obtained in the calculation of the cross sections for isotope {sup 238}U for different resonances. Results obtained have proved satisfactory from the standpoint of accuracy. (author)
International Nuclear Information System (INIS)
Palma, Daniel Artur Pinheiro; Martinez, Aquilino Senra; Goncalves, Alessandro C.
2008-01-01
The calculation of the Doppler broadening function and the interference term are very important in the generation of nuclear data. Recent papers have proposed analytical formulations for both functions and, despite their being simple and precise, they contain the error function with a complex argument. With the intention of simplifying the mathematical treatment two approximations are proposed in this paper. The first one consists of using an expansion in the form of series to treat the error function. The other approximation is based on simplifications in the differential equations that govern the Doppler broadening function. For validation purpose the result obtained is compared to the one obtained in the calculation of the cross sections for isotope 238 U for different resonances. Results obtained have proved satisfactory from the standpoint of accuracy. (author)
Ultrafast carrier dynamics and third-order nonlinear optical properties of AgInS2/ZnS nanocrystals
Yu, Kuai; Yang, Yang; Wang, Junzhong; Tang, Xiaosheng; Xu, Qing-Hua; Wang, Guo Ping
2018-06-01
Broad photoluminescence (PL) emission, a large Stokes shift and extremely long-lived radiative lifetimes are the characteristics of ternary I–III–VI semiconductor nanocrystals (NCs), such as CuInS2 and AgInS2. However, the lack of understanding regarding the intriguing PL mechanisms and photo-carrier dynamics limits their further applications. Here, AgInS2 and AgInS2/ZnS NCs were chemically synthesized and their carrier dynamics were studied by time-resolved PL spectroscopy. The results demonstrated that the surface defect state, which contributed dominantly to the non-radiative decay processes, was effectively passivated through ZnS alloying. Femtosecond transient absorption spectroscopy was also used to investigate the carrier dynamics, revealing the electron storage at the surface state and donor state. Furthermore, the two photon absorption properties of AgInS2 and AgInS2/ZnS NCs were measured using an open-aperture Z-scan technique. The improved third-order nonlinear susceptibility {χ }(3) of AgInS2 through ZnS alloying demonstrates potential application in two photon PL biological imaging.
Almeida, Gustavo F. B.; Almeida, Juliana M. P.; Martins, Renato J.; De Boni, Leonardo; Arnold, Craig B.; Mendonca, Cleber R.
2018-01-01
The development of advanced photonics devices requires materials with large optical nonlinearities, fast response times and high optical transparency, while at the same time allowing for the micro/nano-processing needed for integrated photonics. In this context, glasses have been receiving considerable attention given their relevant optical properties which can be specifically tailored by compositional control. Corning Gorilla® Glass (strengthened alkali aluminosilicate glass) is well-known for its use as a protective screen in mobile devices, and has attracted interest as a potential candidate for optical devices. Therefore, it is crucial not only to expand the knowledge on the fabrication of waveguides in Gorilla Glass under different regimes, but also to determine its nonlinear optical response, both using fs-laser pulses. Thus, this paper reports, for the first time, characterization of the third-order optical nonlinearities of Gorilla Glass, as well as linear and nonlinear characterization of waveguide written with femtosecond pulses under the low repetition rate regime (1 kHz).
International Nuclear Information System (INIS)
Schneider, M.; Wormit, M.; Dreuw, A.; Soshnikov, D. Yu.; Trofimov, A. B.; Holland, D. M. P.; Powis, I.; Antonsson, E.; Patanen, M.; Nicolas, C.; Miron, C.
2015-01-01
The valence-shell ionization spectrum of bromobenzene, as a representative halogen substituted aromatic, was studied using the non-Dyson third-order algebraic-diagrammatic construction [nD-ADC(3)] approximation for the electron propagator. This method, also referred to as IP-ADC(3), was implemented as a part of the Q-Chem program and enables large-scale calculations of the ionization spectra, where the computational effort scales as n 5 with respect to the number of molecular orbitals n. The IP-ADC(3) scheme is ideally suited for investigating low-lying ionization transitions, so fresh insight could be gained into the cationic state manifold of bromobenzene. In particular, the present IP-ADC(3) calculations with the cc-pVTZ basis reveal a whole class of low-lying low-intensity two-hole-one-particle (2h-1p) doublet and quartet states, which are relevant to various photoionization processes. The good qualitative agreement between the theoretical spectral profile for the valence-shell ionization transitions generated with the smaller cc-pVDZ basis set and the experimental photoelectron spectrum measured at a photon energy of 80 eV on the PLÉIADES beamline at the Soleil synchrotron radiation source allowed all the main features to be assigned. Some theoretical aspects of the ionization energy calculations concerning the use of various approximation schemes and basis sets are discussed
Karthigha, S.; Krishnamoorthi, C.
2018-03-01
An organic quinolinium derivative nonlinear optical (NLO) crystal, 1-ethyl-2-[2-(4-nitro-phenyl)-vinyl]-quinolinium iodide (PNQI) was synthesized and successfully grown by slow evaporation solution growth technique. Formation of a crystalline compound was confirmed by single crystal X-ray diffraction. The quinolinium compound PNQI crystallizes in the triclinic crystal system with a centrosymmetric space group of P-1 symmetry. The molecular structure of PNQI was confirmed by 1H NMR and 13C NMR spectral studies. The thermal properties of the crystal have been investigated by thermogravimetric (TG) and differential scanning calorimetry (DSC) studies. The optical characteristics obtained from UV-Vis-NIR spectral data were described and the cut-off wavelength observed at 506 nm. The etching study was performed to analyse the growth features of PNQI single crystal. The third order NLO properties such as nonlinear refractive index (n2), nonlinear absorption coefficient (β) and nonlinear susceptibility (χ (3)) of the crystal were investigated using Z-scan technique at 632.8 nm of Hesbnd Ne laser.
Directory of Open Access Journals (Sweden)
2008-11-01
Full Text Available A novel poly(urethane-imide (PUI containing dispersed red chromophore was synthesized. The PUI was characterized by FT-IR, UV-Vis, DSC and TGA. The results of DSC and TGA indicated that the PUI exhibited high thermal stability up to its glass-transition temperature (Tg of 196°C and 5% heat weight loss temperature of 229°C. According to UV-Vis spectrum and working curve, the maximum molar absorption coefficient and absorption wavelength were measured. They were used to calculate the third-order nonlinear optical coefficient χ(3. At the same time, the chromophore density of PUI, nonlinear refractive index coefficient and molecular hyperpolarizability of PUI were obtained. The fluorescence spectra of PUI and model compound DR-19 were determined at excitation wavelength 300 nm. The electron donor and acceptor in polymer formed the exciplex through the transfer of the electric charges. The results show that the poly(urethane-imide is a promising candidate for application in optical devices.
Directory of Open Access Journals (Sweden)
Ruzanna Kh. Makaova
2017-12-01
Full Text Available In this paper we study the boundary value problem for a degenerating third order equation of hyperbolic type in a mixed domain. The equation under consideration in the positive part of the domain coincides with the Hallaire equation, which is a pseudoparabolic type equation. Moreover, in the negative part of the domain it coincides with a degenerating hyperbolic equation of the first kind, the particular case of the Bitsadze–Lykov equation. The existence and uniqueness theorem for the solution is proved. The uniqueness of the solution to the problem is proved with the Tricomi method. Using the functional relationships of the positive and negative parts of the domain on the degeneration line, we arrive at the convolution type Volterra integral equation of the 2nd kind with respect to the desired solution by a derivative trace. With the Laplace transform method, we obtain the solution of the integral equation in its explicit form. At last, the solution to the problem under study is written out explicitly as the solution of the second boundary-value problem in the positive part of the domain for the Hallaire equation and as the solution to the Cauchy problem in the negative part of the domain for a degenerate hyperbolic equation of the first kind.
Meng, Lingyi; He, Shanshan; Zhao, Xin Sheng
2017-12-21
Fluorescence correlation spectroscopy (FCS) encodes the information on the equilibrium constant (K), the relative fluorescence brightness of fluorophore (Q), and the forward and backward reaction rate constants (k + and k - ) on a physical or chemical relaxation. However, it has been a long-standing problem to completely resolve the FCS data to get the thermodynamic and kinetic information. Recently, we have solved the problem for fluorescence autocorrelation spectroscopy (FACS). Here, we extend the method to fluorescence cross-correlation spectroscopy (FCCS), which appears when FCS is coupled with fluorescence resonance energy transfer (FRET). Among 12 total second-order and third-order pre-exponential factors in a relaxation process probed by the FRET-FCS technique, 3 are independent. We presented and discussed 3 sets of explicit solutions to use these pre-exponential factors to calculate K and Q. Together with the relaxation time, the acquired K will allow people to obtain k + and k - , so that the goal of deciphering the FRET-FCS data will be fully reached. The theory is verified by extensive computer simulations and tested experimentally on a system of oligonucleotide hybridization.
TMS Over the Cerebellum Interferes with Short-term Memory of Visual Sequences.
Ferrari, C; Cattaneo, Z; Oldrati, V; Casiraghi, L; Castelli, F; D'Angelo, E; Vecchi, T
2018-04-30
Growing evidence suggests that the cerebellum is not only involved in motor functions, but it significantly contributes to sensory and cognitive processing as well. In particular, it has been hypothesized that the cerebellum identifies recurrent serial events and recognizes their violations. Here we used transcranial magnetic stimulation (TMS) to shed light on the role of the cerebellum in short-term memory of visual sequences. In two experiments, we found that TMS over the right cerebellar hemisphere impaired participants' ability to recognize the correct order of appearance of geometrical stimuli varying in shape and/or size. In turn, cerebellar TMS did not affect recognition of highly familiar short sequences of letters or numbers. Overall, our data suggest that the cerebellum is involved in memorizing the order in which (concatenated) stimuli appear, this process being important for sequence learning.
Gieseking, Rebecca L.
2015-06-22
Organic π-conjugated materials have been widely used for a variety of nonlinear optical (NLO) applications. Molecules with negative real components Re(γ) of the third-order polarizability, which leads to nonlinear refraction in macroscopic systems, have important benefits for several NLO applications. However, few organic systems studied to date have negative Re(γ) in the long wavelength limit, and all inorganic materials show positive nonlinear refraction in this limit. Here, we introduce a new class of molecules of the form X(C6H5)4, where X = B-, C, N+, and P+, that have negative Re(γ). The molecular mechanism for the NLO properties in these systems is very different from those in typical linear conjugated systems: these systems have a band of excited states involving single-electron excitations within the π-system, several of which have significant coupling to the ground state. Thus, Re(γ) cannot be understood in terms of a simplified essential-state model and must be analyzed in the context of the full sum-over-states expression. Although Re(γ) is significantly smaller than that of other commonly-studied NLO chromophores, the introduction of a new molecular architecture offering the potential for a negative Re(γ) introduces new avenues of molecular design for NLO applications.
Gieseking, Rebecca L.; Ensley, Trenton R.; Hu, Honghua; Hagan, David J.; Risko, Chad; Van Stryland, Eric W.; Bredas, Jean-Luc
2015-01-01
Organic π-conjugated materials have been widely used for a variety of nonlinear optical (NLO) applications. Molecules with negative real components Re(γ) of the third-order polarizability, which leads to nonlinear refraction in macroscopic systems, have important benefits for several NLO applications. However, few organic systems studied to date have negative Re(γ) in the long wavelength limit, and all inorganic materials show positive nonlinear refraction in this limit. Here, we introduce a new class of molecules of the form X(C6H5)4, where X = B-, C, N+, and P+, that have negative Re(γ). The molecular mechanism for the NLO properties in these systems is very different from those in typical linear conjugated systems: these systems have a band of excited states involving single-electron excitations within the π-system, several of which have significant coupling to the ground state. Thus, Re(γ) cannot be understood in terms of a simplified essential-state model and must be analyzed in the context of the full sum-over-states expression. Although Re(γ) is significantly smaller than that of other commonly-studied NLO chromophores, the introduction of a new molecular architecture offering the potential for a negative Re(γ) introduces new avenues of molecular design for NLO applications.
Xu, Kuan-Man; Cheng, Anning
2014-05-01
A high-resolution cloud-resolving model (CRM) embedded in a general circulation model (GCM) is an attractive alternative for climate modeling because it replaces all traditional cloud parameterizations and explicitly simulates cloud physical processes in each grid column of the GCM. Such an approach is called "Multiscale Modeling Framework." MMF still needs to parameterize the subgrid-scale (SGS) processes associated with clouds and large turbulent eddies because circulations associated with planetary boundary layer (PBL) and in-cloud turbulence are unresolved by CRMs with horizontal grid sizes on the order of a few kilometers. A third-order turbulence closure (IPHOC) has been implemented in the CRM component of the super-parameterized Community Atmosphere Model (SPCAM). IPHOC is used to predict (or diagnose) fractional cloudiness and the variability of temperature and water vapor at scales that are not resolved on the CRM's grid. This model has produced promised results, especially for low-level cloud climatology, seasonal variations and diurnal variations (Cheng and Xu 2011, 2013a, b; Xu and Cheng 2013a, b). Because of the enormous computational cost of SPCAM-IPHOC, which is 400 times of a conventional CAM, we decided to bypass the CRM and implement the IPHOC directly to CAM version 5 (CAM5). IPHOC replaces the PBL/stratocumulus, shallow convection, and cloud macrophysics parameterizations in CAM5. Since there are large discrepancies in the spatial and temporal scales between CRM and CAM5, IPHOC used in CAM5 has to be modified from that used in SPCAM. In particular, we diagnose all second- and third-order moments except for the fluxes. These prognostic and diagnostic moments are used to select a double-Gaussian probability density function to describe the SGS variability. We also incorporate a diagnostic PBL height parameterization to represent the strong inversion above PBL. The goal of this study is to compare the simulation of the climatology from these three
Directory of Open Access Journals (Sweden)
Peter Edward Wais
2014-04-01
Full Text Available The mere presence of irrelevant external stimuli results in interference with the fidelity of details retrieved from long-term memory (LTM. Recent studies suggest that distractibility during LTM retrieval occurs when the focus of resource-limited, top-down mechanisms that guide the selection of relevant mnemonic details is disrupted by representations of external distractors. We review findings from four studies that reveal distractibility during episodic retrieval. The approach cued participants to recall previously studied visual details when their eyes were closed, or were open and irrelevant visual information was present. The results showed a negative impact of the distractors on the fidelity of details retrieved from LTM. An fMRI experiment using the same paradigm replicated the behavioral results and found that diminished episodic memory was associated with the disruption of functional connectivity in whole-brain networks. Specifically, network connectivity supported recollection of details based on visual imagery when eyes were closed, but connectivity declined in the presence of visual distractors. Another experiment using auditory distractors found equivalent effects for auditory and visual distraction during cued recall, suggesting that the negative impact of distractibility is a domain-general phenomenon in LTM. Comparisons between older and younger adults revealed an aging-related increase in the negative impact of distractibility on retrieval of LTM. Finally, a new study that compared categorization abilities between younger and older adults suggests a cause underlying age-related decline of visual details in LTM. The sum of our findings suggests that cognitive control resources, although limited, have the capability to resolve interference from distractors during tasks of moderate effort, but these resources are overwhelmed when additional processes associated with episodic retrieval, or categorization of complex prototypes, are
Misra, J. C.; Mallick, B.; Sinha, A.; Roy Chowdhury, A.
2018-05-01
In the case of steady flow of a fluid under the combined influence of external electric and magnetic fields, the fluid moves forward by forming an axial momentum boundary layer. With this end in view a study has been performed here to investigate the problem of entropy generation during electroosmotically modulated flow of a third-order electrically conducting fluid flowing on a microchannel bounded by silicon-made parallel plates under the influence of a magnetic field, by paying due consideration to the steric effect. The associated mechanism of heat transfer has also been duly taken care of, by considering Cattaneo-Christov heat flux. A suitable finite difference scheme has been developed for the numerical procedure. A detailed study of the velocity and temperature distributions has been made by considering their variations with respect to different physical parameters involved in the problem. The results of numerical computation have been displayed graphically. The computational work has been carried out by considering blood as the working fluid, with the motivation of exploring some interesting phenomena in the context of hemodynamical flow in micro-vessels. Among other variables, parametric variations of the important physical variables, viz. i) skin friction and ii) Nusselt number have been investigated. The study confirms that the random motion of the fluid particles can be controlled by a suitable adjustment of the intensity of an externally applied magnetic field in the transverse direction. It is further revealed that the Nusselt number diminishes, as the Prandtl number gradually increases; however, a steady increase in the Nusselt number occurs with increase in thermal relaxation. Entropy generation is also found to be enhanced with increase in Joule heating. The results of the present study have also been validated in a proper manner.
Nakano, Masayoshi; Kishi, Ryohei; Yoneda, Kyohei; Inoue, Yudai; Inui, Tomoya; Shigeta, Yasuteru; Kubo, Takashi; Champagne, Benoît
2011-08-11
The third-order nonlinear optical (NLO) properties, at the molecular level, the static second hyperpolarizabilities, γ, of supermolecular systems composed of phenalenyl and pyrene rings linked by acetylene units are investigated by employing the long-range corrected spin-unrestricted density functional theory, LC-UBLYP, method. The phenalenyl based superethylene, superallyl, and superbutadiene in their lowest spin states have intermediate diradical characters and exhibit larger γ values than the closed-shell pyrene based superpolyene systems. The introduction of a positive charge into the phenalenyl based superallyl radical changes the sign of γ and enhances its amplitude by a factor of 35. Although such sign inversion is also observed in the allyl radical and cation systems in their ground state equilibrium geometries, the relative amplitude of γ is much different, that is, |γ(regular allyl cation)/γ(regular allyl radical)| = 0.61 versus |γ(phenalenyl based superallyl cation)/γ(phenalenyl based superallyl radical)| = 35. In contrast, the model ethylene, allyl radical/cation, and butadiene systems with stretched carbon-carbon bond lengths (2.0 Å), having intermediate diradical characters, exhibit similar γ features to those of the phenalenyl based superpolyene systems. This exemplifies that the size dependence of γ as well as its sign change by introducing a positive charge on the phenalenyl based superpolyene systems originate from their intermediate diradical characters. In addition, the change from the lowest to the highest π-electron spin states significantly reduces the γ amplitudes of the neutral phenalenyl based superpolyene systems. For phenalenyl based superallyl cation, the sign inversion of γ (from negative to positive) is observed upon switching between the singlet and triplet states, which is predicted to be associated with a modification of the balance between the positive and negative contributions to γ. The present study paves the way
Gajewski, Patrick D; Falkenstein, Michael
2015-08-01
Aging is associated with compromised executive control functions. Several lines of evidence point to beneficial effects of physical activity on cognition which indicate that regular physical activity may counteract the age-related decline of some executive functions. Here, we investigate the effects of lifelong physical activity (about 50 years) on interference processing in two matched groups of 20 physically high active and 20 low active healthy older men using event-related potentials (ERPs). In a low interference block of the Stroop task, participants had to indicate the meaning of color-words, while color was either compatible or incompatible with the meaning. In the high interference block, participants were asked to respond according to the ink color of the word and to ignore its meaning. Physically active seniors showed faster reaction times, lower individual variability in reaction times, and higher accuracy compared to low active seniors, particularly in the high interference block. This result was confirmed in the classic paper-and-pencil version of the Stroop task showing higher interference score in the low active than high active individuals. ERPs revealed a shorter latency of the P2 and generally more negative amplitudes of the fronto-central N2 and N450 components in the high active group compared to the low active group. The amount of interference was negatively correlated with objectively measured fitness and self-reported physical activity. The positive effect of physical fitness on interference processing in the behavioral data was related to N2 and N450 amplitudes. Taken together, this suggests that seniors reporting long-term physical activity may exhibit generally enhanced activity in the frontal cortex which enables more efficient interference resolution in the Stroop task. Copyright © 2015 Elsevier Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Ahmed Mohammed Saleh Alduais
2015-12-01
Full Text Available Purpose: To see if there is a correlation between interference and short-term memory recall and to examine interference as a factor affecting memory recalling of Arabic and abstract words through free, cued, and serial recall tasks. Method: Four groups of undergraduates in King Saud University, Saudi Arabia participated in this study. The first group consisted of 9 undergraduates who were trained to perform three types of recall for 20 Arabic abstract and concrete words. The second, third and fourth groups consisted of 27 undergraduates where each group was trained only to perform one recall type: free recall, cued recall and serial recall respectively. Interference (short-term memory interruption was the independent variable and a number of recalled abstract and concrete words was the dependent variable. The used materials in this study were: abstract and concrete words classification form based on four factors was distributed to the participants (concreteness, imageability, meaningfulness, and age of acquisition, three oral recall forms, three written recall forms, and observation sheets for each type of recall. Also, three methods were used: auditory, visual, and written methods. Results: Findings indicated that interference effect on short-term memory recall of Arabic abstract and concrete words was not significant especially in the case of free and serial recall paradigms. The difference between the total number of recalled Arabic abstract and concrete words was also very slight. One other the hand, we came to the conclusion that Pearson’s correlation between interference at these memory recall paradigms (M: 1.66, SD= .47 and the short-term memory recall (M: 1.75, SD= .43 supported the research hypothesis that those participants with oral interruptions tended to recall slightly less Arabic abstract and concrete words, whereas those participants with no oral interruptions would tend to recall slightly more Arabic abstract and concrete
Hayton, D. J.; Khudchencko, A.; Pavelyev, D. G.; Hovenier, J. N.; Baryshev, A.; Gao, J. R.; Kao, T. Y.; Hu, Q.; Reno, J. L.; Vaks, V.
2013-01-01
We report on the phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser (QCL) using a room temperature GaAs/AlAs superlattice diode as both a frequency multiplier and an internal harmonic mixer. A signal-to-noise level of 60 dB is observed in the intermediate frequency
Hayton, D.J.; Khudchenko, A.; Pavelyev, D.G.; Hovenier, J.N.; Baryshev, A.; Gao, J.R.; Kao, T.Y.; Hu, Q.; Reno, J.L.; Vaks, V.
2013-01-01
We report on the phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser (QCL) using a room temperature GaAs/AlAs superlattice diode as both a frequency multiplier and an internal harmonic mixer. A signal-to-noise level of 60?dB is observed in the intermediate frequency
Rijmen, Frank; Jeon, Minjeong; von Davier, Matthias; Rabe-Hesketh, Sophia
2014-01-01
Second-order item response theory models have been used for assessments consisting of several domains, such as content areas. We extend the second-order model to a third-order model for assessments that include subdomains nested in domains. Using a graphical model framework, it is shown how the model does not suffer from the curse of…
Energy Technology Data Exchange (ETDEWEB)
Montanez, I.P.; Droser, M.L. (Univ. of California, Riverside (United States))
1991-03-01
The Middle to Late Cambrian Bonanza King Formation (CA, NV) is characterized by superimposed scales of cyclicity. Small-scale cycles (0.5 to 10m) occur as shallowing-upward peritidal and subtidal cycles that repeat at high frequencies (10{sup 4} to 10{sup 5}). Systematic changes in stacking patterns of meter-scale cycles define several large-scale (50-250 m) third-order depositional sequences in the Bonanza King Formation. Third-order depositional sequences can be traced within ranges and correlated regionally across the platform. Peritidal cycles in the Bonanza King Formation are both subtidal- and tidal flat-dominated. Tidal flat-dominated cycles consist of muddy bases grading upward into thrombolites or columnar stromatolites all capped by planar stromatolites. Subtidal cycles in the Bonanza King Formation consist of grainstone bases that commonly fine upward and contain stacked hardgrounds. These are overlain by digitate-algal bioherms with grainstone channel fills and/or bioturbated ribbon carbonates with grainstone lenses. Transgressive depositional facies of third-order depositional sequences consist primarily of stacks of subtidal-dominated pertidial cycles and subtidal cycles, whereas regressive depositional facies are dominated by stacks of tidal flat-dominated peritidal cycles and regoliths developed over laminite cycle caps. The use of high frequency cycles in the Bonanza King Formation to delineate regionally developed third-order depositional sequences thus provides a link between cycle stratigraphy and sequence stratigraphy.
Sakian, P.; Mahmoudi, R.; Roermund, van A.H.M.
2011-01-01
An in-depth analysis is performed on the third-order intermodulation distortions (IMD3) in the switching pair of active CMOS mixers. The nonlinear time-varying switching pair is described by a hypothetical circuit composed of a nonlinear time-invariant circuit cascaded with a linear time-varying
Fyfe, Jackson J; Bartlett, Jonathan D; Hanson, Erik D; Stepto, Nigel K; Bishop, David J
2016-01-01
We determined the effect of concurrent training incorporating either high-intensity interval training (HIT) or moderate-intensity continuous training (MICT) on maximal strength, counter-movement jump (CMJ) performance, and body composition adaptations, compared with single-mode resistance training (RT). Twenty-three recreationally-active males (mean ± SD: age, 29.6 ± 5.5 y; [Formula: see text], 44 ± 11 mL kg -1 ·min -1 ) underwent 8 weeks (3 sessions·wk -1 ) of either: (1) HIT combined with RT (HIT+RT group, n = 8), (2) work-matched MICT combined with RT (MICT+RT group, n = 7), or (3) RT performed alone (RT group, n = 8). Measures of aerobic capacity, maximal (1-RM) strength, CMJ performance and body composition (DXA) were obtained before (PRE), mid-way (MID), and after (POST) training. Maximal (one-repetition maximum [1-RM]) leg press strength was improved from PRE to POST for RT (mean change ± 90% confidence interval; 38.5 ± 8.5%; effect size [ES] ± 90% confidence interval; 1.26 ± 0.24; P body lean mass was similarly increased for RT (4.1 ± 2.0%; ES; 0.33 ± 0.16; P = 0.023) and MICT+RT (3.6 ± 2.4%; ES; 0.45 ± 0.30; P = 0.052); however, this change was attenuated for HIT+RT (1.8 ± 1.6%; ES; 0.13 ± 0.12; P = 0.069). We conclude that concurrent training incorporating either HIT or work-matched MICT similarly attenuates improvements in maximal lower-body strength and indices of CMJ performance compared with RT performed alone. This suggests endurance training intensity is not a critical mediator of interference to maximal strength gain during short-term concurrent training.
Directory of Open Access Journals (Sweden)
Mei Mingxiang
2013-01-01
Full Text Available The Caledonian orogeny at the end of the Silurian resulted in great changes in the palaeogeography in the Yunnan-Guizhou-Guangxi area of South China; the continental area of the Early Paleozoic evolved into the extensive Dian-Qian-Gui Sea in the Late Paleozoic. Early in the Devonian, as a result of a major transgression, seawater encroached gradually from the south to the north and clastic facies were deposited. Carbonate deposition was then established in the Yunnan-Guizhou-Guangxi area, with a palaeogeography marked by attached platforms, isolated platforms and narrow basins. As a result of the Ziyun movement towards the end of the Devonian, the Upper Devonian strata are regressive and thin out from the open-sea to the land areas. A study of the nature and distribution of sedimentary facies in space and time recognises 13 third-order sequences in the Devonian strata in Yunnan-Guizhou-Guangxi area, and these form two second-order sequences. The strata of the Lower Devonian comprise 5 third-order sequences (SQ1 to SQ5, which are dominated by transgressive clastics. 4 third-order sequences (SQ6 to SQ9 in the Middle Devonian are characterized by alternations of transgressive clastics and highstand carbonates. In the Upper Devonian, carbonates constitute 4 third-order sequences (SQ10 to SQ13, which are generally marked by the transgressive limestones and highstand dolomites. On the basis of earlier biostratigraphic studies, sea-level changes represented by the third-order sequences with their different facies successions are explored, and the sequence stratigraphic framework is established. Therefore, the Devonian strata in the study area provide an example for further understanding of depositional trends within the sequence-stratigraphic framework.
International Nuclear Information System (INIS)
Gu, X.; Luo, Y.; Fischer, W.
2010-01-01
In the preparation for the 2011 RHIC 250 GeV polarized proton (pp) run, both experiment and simulation were carried out to investigate the possibility to accelerate the proton beam with a vertical tune near 2/3. It had been found experimentally in Run-9 that accelerating the proton beam with a vertical tune close to 2/3 will greatly benefit the transmission of the proton polarization. In this note, we report the calculated dynamic apertures with the 100 GeV Au run and 250 GeV proton run lattices with vertical tunes close to the third order resonance. We will compare the third order resonance band width between the beam experiment and the simulation with the 100 GeV Au lattices. And we also will compare the calculated resonance band width between the 100 GeV Au and 250 GeV proton run lattices.
Saripalli, Ravi Kiran; Katturi, Naga Krishnakanth; Soma, Venugopal Rao; Bhat, H. L.; Elizabeth, Suja
2017-12-01
The linear, second order, and third order nonlinear optical properties of glucuronic acid γ-lactone single crystals were investigated. The optic axes and principal dielectric axes were identified through optical conoscopy and the principal refractive indices were obtained using the Brewster's angle method. Conic sections were observed which is perceived to be due to spontaneous non-collinear phase matching. The direction of collinear phase matching was determined and the deff evaluated in this direction was 0.71 pm/V. Open and closed aperture Z-scan measurements with femtosecond pulses revealed high third order nonlinearity in the form of self-defocusing, two-photon absorption, as well as saturable absorption.
The Role of Test Expectancy in the Build-Up of Proactive Interference in Long-Term Memory
Weinstein, Yana; Gilmore, Adrian W.; Szpunar, Karl K.; McDermott, Kathleen B.
2014-01-01
We examined the hypothesis that interpolated testing in a multiple list paradigm protects against proactive interference by sustaining test expectancy during encoding. In both experiments, recall on the last of 5 word lists was compared between 4 conditions: a tested group who had taken tests on all previous lists, an untested group who had not…
International Nuclear Information System (INIS)
Endo, Tomohiro; Kitamura, Yasunori; Yamane, Yoshihiro
2003-01-01
We have studied a measurement of subcriticality by using the neutron correlation method. Furuhashi proposed an absolute measurement of subcriticality by using the third order neutron correlation factor X in addition to the second order neutron correlation factor Y. In actual experiments, the number of neutron counts data is not infinity so that we take the effect of the finite nature of the neutron counts data into account. We derived new formulas in consideration of the number of data and verified them. (author)
Beshtokov, M. Kh.
2017-12-01
Boundary value problems for loaded third-order pseudo-parabolic equations with variable coefficients are considered. A priori estimates for the solutions of the problems in the differential and difference formulations are obtained. These a priori estimates imply the uniqueness and stability of the solution with respect to the initial data and the right-hand side on a layer, as well as the convergence of the solution of each difference problem to the solution of the corresponding differential problem.
Beshtokov, M. Kh.
2016-10-01
A nonlocal boundary value problem for a degenerating third-order pseudo-parabolic equation with variable coefficients is considered. For solving this problem, a priori estimates in the differential and difference forms are obtained. The a priori estimates imply the uniqueness and stability of the solution on a layer with respect to the initial data and the right-hand side and the convergence of the solution of the difference problem to the solution of the differential problem.
Directory of Open Access Journals (Sweden)
Wei Han
2008-01-01
Full Text Available Several existence theorems of twin positive solutions are established for a nonlinear m-point boundary value problem of third-order p-Laplacian dynamic equations on time scales by using a fixed point theorem. We present two theorems and four corollaries which generalize the results of related literature. As an application, an example to demonstrate our results is given. The obtained conditions are different from some known results.
Chen, Yong; Yan, Zhenya
2016-03-22
Solitons are of the important significant in many fields of nonlinear science such as nonlinear optics, Bose-Einstein condensates, plamas physics, biology, fluid mechanics, and etc. The stable solitons have been captured not only theoretically and experimentally in both linear and nonlinear Schrödinger (NLS) equations in the presence of non-Hermitian potentials since the concept of the parity-time -symmetry was introduced in 1998. In this paper, we present novel bright solitons of the NLS equation with third-order dispersion in some complex -symmetric potentials (e.g., physically relevant -symmetric Scarff-II-like and harmonic-Gaussian potentials). We find stable nonlinear modes even if the respective linear -symmetric phases are broken. Moreover, we also use the adiabatic changes of the control parameters to excite the initial modes related to exact solitons to reach stable nonlinear modes. The elastic interactions of two solitons are exhibited in the third-order NLS equation with -symmetric potentials. Our results predict the dynamical phenomena of soliton equations in the presence of third-order dispersion and -symmetric potentials arising in nonlinear fiber optics and other physically relevant fields.
International Nuclear Information System (INIS)
Xie, Wenfang
2014-01-01
The optical properties of a neutral donor in a ZnS/InP/ZnSe core/shell spherical quantum dot have been investigated using the variational method and the compact density-matrix approach. Two parametric potential is chosen as a confinement potential for the shell. Considering the band structure of the system it is assumed that electron is localized in InP shell. It is assumed that the impurity is located in the center of quantum dot core (ZnS). The photoionization cross section as well as the third-order nonlinear optical susceptibility of third harmonic generation has been calculated. The results show that the photoionization and the third-order nonlinear optical susceptibility of a donor in a core/shell spherical quantum dot are strongly affected by the shell thickness. We found that small applied shell thickness will lead to a significant blue shift of the peak positions in the optical spectrum. This kind of structure gives an opportunity to tune and control the photoionization and the third-order nonlinear optical susceptibility of third harmonic generation of a donor impurity by changing the shell thickness
A Third-Order p-Laplacian Boundary Value Problem Solved by an SL(3,ℝ Lie-Group Shooting Method
Directory of Open Access Journals (Sweden)
Chein-Shan Liu
2013-01-01
Full Text Available The boundary layer problem for power-law fluid can be recast to a third-order p-Laplacian boundary value problem (BVP. In this paper, we transform the third-order p-Laplacian into a new system which exhibits a Lie-symmetry SL(3,ℝ. Then, the closure property of the Lie-group is used to derive a linear transformation between the boundary values at two ends of a spatial interval. Hence, we can iteratively solve the missing left boundary conditions, which are determined by matching the right boundary conditions through a finer tuning of r∈[0,1]. The present SL(3,ℝ Lie-group shooting method is easily implemented and is efficient to tackle the multiple solutions of the third-order p-Laplacian. When the missing left boundary values can be determined accurately, we can apply the fourth-order Runge-Kutta (RK4 method to obtain a quite accurate numerical solution of the p-Laplacian.
Directory of Open Access Journals (Sweden)
Jackson J Fyfe
2016-11-01
-matched MICT similarly attenuates improvements in maximal lower-body strength and indices of CMJ performance compared with RT performed alone. This suggests endurance training intensity is not a critical mediator of interference to maximal strength gain during short-term concurrent training.
Oishi, Masaki; Shinozaki, Tomohisa; Hara, Hikaru; Yamamoto, Kazunuki; Matsusue, Toshio; Bando, Hiroyuki
2018-05-01
The elliptical polarization dependence of the two-photon absorption coefficient β in InP has been measured by the extended Z-scan technique for thick materials in the wavelength range from 1640 to 1800 nm. The analytical formula of the Z-scan technique has been extended with consideration of multiple reflections. The Z-scan results have been fitted very well by the formula and β has been evaluated accurately. The three independent elements of the third-order nonlinear susceptibility tensor in InP have also been determined accurately from the elliptical polarization dependence of β.
International Nuclear Information System (INIS)
Bahedi, K.; Addou, M.; El Jouad, M.; Sofiani, Z.; Alaoui Lamrani, M.; El Habbani, T.; Fellahi, N.; Bayoud, S.; Dghoughi, L.; Sahraoui, B.; Essaidi, Z.
2009-01-01
Zinc oxide (ZnO) and zirconium doped zinc oxide (ZnO:Zr) thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 500 deg. C using zinc and zirconium chlorides as precursors. Effects of zirconium doping agent and surface roughness on the nonlinear optical properties were investigated in detail using atomic force microscopy (AFM) and third harmonic generation (THG) technique. The best value of nonlinear optical susceptibility χ (3) was obtained from the doped films with less roughness. A strong third order nonlinear optical susceptibility χ (3) = 20.12 x 10 -12 (esu) of the studied films was found for the 3% doped sample.
DEFF Research Database (Denmark)
Zhang, Chunjiang; Zhao, Xiaojun; Wang, Xiaohuan
2018-01-01
in the grid voltages, the general SOGI’s performance suffers from its generated dc effect in the lagging sine signal at the output. Therefore, in this paper, a mixed second- and third-order generalized integrator (MSTOGI) is proposed to eliminate this effect caused by the dc offset of grid voltages......The second order generalized integrator (SOGI) has been widely used to implement grid synchronization for grid-connected inverters, and from grid voltages it is able to extract the fundamental components with an output of two orthogonal sinusoidal signals. However, if there is a dc offset existing...
Ryuichi, TAKAHASHI; Department of Physics and Astrophysics, Nagoya University
2008-01-01
We investigate the third-order density perturbation and the one-loop correction to the linear power spectrum in the dark-energy cosmological model. Our main interest is to understand the dark-energy effect on baryon acoustic oscillations in a quasi-nonlinear regime (k≈0.1h/Mpc). Analytical solutions and simple fitting formulae are presented for the dark-energy model with the general time-varying equation of state w(a). It turns out that the power spectrum coincides with the approximate res...
Directory of Open Access Journals (Sweden)
Max Berniker
2011-10-01
Full Text Available Recent studies suggest that motor adaptation is the result of multiple, perhaps linear processes each with distinct time scales. While these models are consistent with some motor phenomena, they can neither explain the relatively fast re-adaptation after a long washout period, nor savings on a subsequent day. Here we examined if these effects can be explained if we assume that the CNS stores and retrieves movement parameters based on their possible relevance. We formalize this idea with a model that infers not only the sources of potential motor errors, but also their relevance to the current motor circumstances. In our model adaptation is the process of re-estimating parameters that represent the body and the world. The likelihood of a world parameter being relevant is then based on the mismatch between an observed movement and that predicted when not compensating for the estimated world disturbance. As such, adapting to large motor errors in a laboratory setting should alert subjects that disturbances are being imposed on them, even after motor performance has returned to baseline. Estimates of this external disturbance should be relevant both now and in future laboratory settings. Estimated properties of our bodies on the other hand should always be relevant. Our model demonstrates savings, interference, spontaneous rebound and differences between adaptation to sudden and gradual disturbances. We suggest that many issues concerning savings and interference can be understood when adaptation is conditioned on the relevance of parameters.
Maidur, Shivaraj R.; Patil, Parutagouda Shankaragouda; Rao, S. Venugopal
2018-04-01
In this paper, we present the third-order nonlinear optical (NLO) studies of 1,3-bis(3,4-dimethoxyphenyl)prop-2-en-1-one (abbreviated as VDMC). The chalcone was synthesized by Claisen-Schmidt condensation method. The third-order nonlinear optical properties were evaluated using standard, well-known Z-scan technique under femtosecond laser regime (150 fs, 900 nm) with two different laser repetition rates 500 Hz and 80 MHz. Open aperture studies showed that the molecule possess two photon absorption with the coefficients in the order 10-9 cmW-1. The closed aperture studies have resulted the negative nonlinear refraction with the coefficients in the order 10-14 cm2W-1. The two-photon absorption cross sections were estimated. Optical limiting properties have been studied and the limiting threshold values were found to be in the range 0.86-2.3 mJ/cm2, which suggests that VDMC has better applications in the field of nonlinear optics.
Patro, L N; Burghaus, O; Roling, B
2017-04-21
We have measured the third-order permittivity spectra ε 3 3 of a monocationic and of a dicationic liquid close to the glass transition temperature by applying ac electric fields with large amplitudes up to 180 kV/cm. A peak ("hump") in the modulus of ε 3 3 is observed for a mono-cationic liquid after subtraction of the dc contribution from the imaginary part of ε 3 3 . We show that the origin of this experimental "hump" is a peak in the imaginary part of ε 3 3 , with the peak height strongly increasing with decreasing temperature. Overall, the spectral shape of the third-order permittivity of both ionic liquids is similar to the predictions of a symmetric double well potential model, although this model does not predict a "hump" in the modulus. In contrast, an asymmetric double well potential model predicts a "hump," but the spectral shape of both the real and imaginary part of ε 3 3 deviates significantly from the experimental spectra. These results show that not only the modulus of ε 3 3 but also its phase is an important quantity when comparing experimental results with theoretical predictions.
Zhang, Feng; Han, Xiangyun
2014-09-01
We report an investigation on the optical third-order nonlinear property of the nonpolar A-plane GaN film. The film sample with a thickness of ~2 μm was grown on an r-plane sapphire substrate by metal-organic chemical vapor deposition system. By performing the Z-scan method combined with a mode-locked femtosecond Ti:sapphire laser (800 nm, 50 fs), the optical nonlinearity of the nonpolar A-plane GaN film was measured with the electric vector E of the laser beam being polarized parallel (//) and perpendicular (⊥) to the c axis of the film. The results show that both the third-order nonlinear absorption coefficient β and the nonlinear refractive index n2 of the sample film possess negative and large values, i.e. β// = -135 ± 29 cm/GW, n2// = -(4.0 ± 0.3) × 10-3 cm2/GW and β⊥ = -234 ± 29 cm/GW, n2⊥ = -(4.9 ± 0.4) × 10-3 cm2/GW, which are much larger than those of conventional C-plane GaN film, GaN bulk, and even the other oxide semiconductors.
International Nuclear Information System (INIS)
Carrillo-Delgado, C; Torres-Torres, C; García-Merino, J A; García-Gil, C I; Khomenko, A V; Trejo-Valdez, M; Martínez-Gutiérrez, H; Torres-Martínez, R
2016-01-01
Measurements of the third-order nonlinear optical properties exhibited by a ZnO thin solid film deposited on a SnO 2 substrate are presented. The samples were prepared by a spray pyrolysis processing route. Scanning electron microscopy analysis and UV–Vis spectroscopy studies were carried out. The picosecond response at 1064 nm was explored by the z-scan technique. A large optical Kerr effect with two-photon absorption was obtained. The inhibition of the nonlinear optical absorption together with a noticeable enhancement in the optical Kerr effect in the sample was achieved by the incorporation of Au nanoparticles into the ZnO film. Additionally, a two-wave mixing configuration at 532 nm was performed and an optical Kerr effect was identified as the main cause of the nanosecond third-order optical nonlinearity. The relaxation time of the photothermal response of the sample was estimated to be about 1 s when the sample was excited by nanosecond single-shots. The rotation of the sample during the nanosecond two-wave mixing experiments was analyzed. It was stated that a non-monotonic relation between rotating frequency and pulse repetition rate governs the thermal contribution to the nonlinear refractive index exhibited by a rotating film. Potential applications for switching photothermal interactions in rotating samples can be contemplated. A rotary logic system dependent on Kerr transmittance in a two-wave mixing experiment was proposed. (paper)
Energy Technology Data Exchange (ETDEWEB)
Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1961-07-01
Various methods of transmission resonance analysis for 's' wave neutrons in time of flight experiments are described in this report. Only the case when the interference term can be neglected is treated in this first part. Results are given relative to a more complete partial area method and also to a new method so-called the width at half depth method. (author) [French] Le present rapport est consacre a l'expose de differentes methodes d'analyse des resonances dues aux neutrons d'ondes 's' dans les experiences de transmission par temps de vol, cette premiere partie traitant uniquement le cas ou l'on peut negliger le terme d'interference. Y figurent en particulier sous forme de reseaux de courbes, les resultats relatifs a une methode des aires partielles amelioree et ceux relatifs a une nouvelle methode dite de la largeur a mi-profondeur. (auteur)
Energy Technology Data Exchange (ETDEWEB)
Lefrancois, Daniel; Dreuw, Andreas, E-mail: dreuw@uni-heidelberg.de [Interdisciplinary Center for Scientific Computing, Ruprecht-Karls University, Im Neuenheimer Feld 205, 69120 Heidelberg (Germany); Rehn, Dirk R. [Departments of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping (Sweden)
2016-08-28
For the calculation of adiabatic singlet-triplet gaps (STG) in diradicaloid systems the spin-flip (SF) variant of the algebraic diagrammatic construction (ADC) scheme for the polarization propagator in third order perturbation theory (SF-ADC(3)) has been applied. Due to the methodology of the SF approach the singlet and triplet states are treated on an equal footing since they are part of the same determinant subspace. This leads to a systematically more accurate description of, e.g., diradicaloid systems than with the corresponding non-SF single-reference methods. Furthermore, using analytical excited state gradients at ADC(3) level, geometry optimizations of the singlet and triplet states were performed leading to a fully consistent description of the systems, leading to only small errors in the calculated STGs ranging between 0.6 and 2.4 kcal/mol with respect to experimental references.
Pramodini, S.; Sudhakar, Y. N.; SelvaKumar, M.; Poornesh, P.
2014-04-01
We present the synthesis and characterization of third-order optical nonlinearity and optical limiting of the conducting polymers poly (aniline-co-o-anisidine) and poly (aniline-co-pyrrole). Nonlinear optical studies were carried out by employing the z-scan technique using a He-Ne laser operating in continuous wave mode at 633 nm. The copolymers exhibited a reverse saturable absorption process and self-defocusing properties under the experimental conditions. The estimated values of βeff, n2 and χ(3) were found to be of the order of 10-2 cm W-1, 10-5 esu and 10-7 esu respectively. Self-diffraction rings were observed due to refractive index change when exposed to the laser beam. The copolymers possess a lower limiting threshold and clamping level, which is essential to a great extent for power limiting devices. Therefore, copolymers of aniline emerge as a potential candidate for nonlinear optical device applications.
Wu, Shaohua; Wu, Xiaozhi; Wang, Rui; Liu, Qing; Gan, Liyong
2014-01-01
Effects of Ni vacancy, Ni antisite in Al sublattice, Cr in Al sublattice, Pt in Ni sublattice on the second-order elastic constants (SOECs) and third-order elastic constants (TOECs) of the B2 NiAl have been investigated using the first-principles methods. Lattice constant and the SOECs of NiAl are in good agreement with the previous results. The brittle/ductile transition map based on Pugh ratio G/B and Cauchy pressure Pc shows that Ni antisite, Cr, Pt and pressure can improve the ductility of NiAl, respectively. Ni vacancy and lower pressure can enhance the Vickers hardness Hv of NiAl. The density of states (DOS) and the charge density difference are also used to analysis the effects of vacancy, Ni antisite, Cr and Pt on the mechanical properties of NiAl, and the results are in consistent with the transition map. © 2014 Elsevier Ltd. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Bahedi, K., E-mail: bahedikhadija@yahoo.com [Laboratoire Optoelectronique et Physico-chimie des Materiaux Universite Ibn Tofail, Faculte des Sciences BP 133 Kenitra 14000, Maroc (Morocco); Addou, M.; El Jouad, M.; Sofiani, Z.; Alaoui Lamrani, M.; El Habbani, T.; Fellahi, N.; Bayoud, S.; Dghoughi, L. [Laboratoire Optoelectronique et Physico-chimie des Materiaux Universite Ibn Tofail, Faculte des Sciences BP 133 Kenitra 14000, Maroc (Morocco); Sahraoui, B.; Essaidi, Z. [Laboratoire POMA, UMR CNRS 6136, Universite d' Angers 2, Bd Lavoisier, 49045 France (France)
2009-02-01
Zinc oxide (ZnO) and zirconium doped zinc oxide (ZnO:Zr) thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 500 deg. C using zinc and zirconium chlorides as precursors. Effects of zirconium doping agent and surface roughness on the nonlinear optical properties were investigated in detail using atomic force microscopy (AFM) and third harmonic generation (THG) technique. The best value of nonlinear optical susceptibility {chi}{sup (3)} was obtained from the doped films with less roughness. A strong third order nonlinear optical susceptibility {chi}{sup (3)} = 20.12 x 10{sup -12} (esu) of the studied films was found for the 3% doped sample.
Kong, Ming; Liu, Yanqiu; Wang, Hui; Luo, Junshan; Li, Dandan; Zhang, Shengyi; Li, Shengli; Wu, Jieying; Tian, Yupeng
2015-01-01
Four novel Zn(II) terpyridine complexes (ZnLCl2, ZnLBr2, ZnLI2, ZnL(SCN)2) based on carbazole derivative group were designed, synthesized and fully characterized. Their photophysical properties including absorption and one-photon excited fluorescence, two-photon absorption (TPA) and optical power limiting (OPL) were further investigated systematically and interpreted on the basis of theoretical calculations (TD-DFT). The influences of different solvents on the absorption and One-Photon Excited Fluorescence (OPEF) spectral behavior, quantum yields and the lifetime of the chromophores have been investigated in detail. The third-order nonlinear optical (NLO) properties were investigated by open/closed aperture Z-scan measurements using femtosecond pulse laser in the range from 680 to 1080 nm. These results revealed that ZnLCl2 and ZnLBr2 exhibited strong two-photon absorption and ZnLCl2 showed superior optical power limiting property.
Devi, S. Reena; Kalaiyarasi, S.; Zahid, I. MD.; Kumar, R. Mohan
2016-11-01
An ionic organic optical crystal of 4-methylpyridinium p-nitrophenolate was grown from methanol by slow evaporation method at ambient temperature. Powder and single crystal X-ray diffraction studies revealed the crystal system and its crystalline perfection. The rocking curve recorded from HRXRD study confirmed the crystal quality. FTIR spectral analysis confirmed the functional groups present in the title compound. UV-visible spectral study revealed the optical window and band gap of grown crystal. The thermal, electrical and surface laser damage threshold properties of harvested crystal were examined by using TGA/DTA, LCR/Impedance Analyzer and Nd:YAG laser system respectively. The third order nonlinear optical property of grown crystal was elucidated by Z-scan technique.
A 1-V 60-μW 85-dB dynamic range continuous-time third-order sigma-delta modulator
International Nuclear Information System (INIS)
Li Yuanwen; Qi Da; Dong Yifeng; Xu Jun; Ren Junyan
2009-01-01
A 1-V third order one-bit continuous-time (CT) EA modulator is presented. Designed in the SMIC mixed-signal 0.13-μm CMOS process, the modulator utilizes active RC integrators to implement the loop filter. An efficient circuit design methodology for the CT ΣΔ modulator is proposed and verified. Low power dissipation is achieved through the use of two-stage class A/AB amplifiers. The presented modulator achieves 81.4-dB SNDR and 85-dB dynamic range in a 20-kHz bandwidth with an over sampling ratio of 128. The total power consumption of the modulator is only 60 μW from a 1-V power supply and the prototype occupies an active area of 0.12 mm 2 . (semiconductor integrated circuits)
Wu, Shaohua
2014-12-01
Effects of Ni vacancy, Ni antisite in Al sublattice, Cr in Al sublattice, Pt in Ni sublattice on the second-order elastic constants (SOECs) and third-order elastic constants (TOECs) of the B2 NiAl have been investigated using the first-principles methods. Lattice constant and the SOECs of NiAl are in good agreement with the previous results. The brittle/ductile transition map based on Pugh ratio G/B and Cauchy pressure Pc shows that Ni antisite, Cr, Pt and pressure can improve the ductility of NiAl, respectively. Ni vacancy and lower pressure can enhance the Vickers hardness Hv of NiAl. The density of states (DOS) and the charge density difference are also used to analysis the effects of vacancy, Ni antisite, Cr and Pt on the mechanical properties of NiAl, and the results are in consistent with the transition map. © 2014 Elsevier Ltd. All rights reserved.
Bharathi, M. Divya; Bhuvaneswari, R.; Srividya, J.; Vinitha, G.; Prithiviraajan, R. N.; Anbalagan, G.
2018-02-01
Single crystals of 8-hydroxyquinolinium 2-carboxy-6-nitrophthalate monohydrate (8HQNP) were obtained from slow evaporation solution growth method using methanol-water (1:1) as a solvent. Powder X-ray diffraction was utilized to compute the unit cell parameters and dislocation density of 8HQNP crystal. The crystalline perfection of the as-grown crystal was investigated by high-resolution X-ray diffraction at room temperature. The molecular structure was analyzed by identifying the functional groups from FT-IR and FT-Raman spectra. The cut-off wavelength and the corresponding optical band gap obtained from an optical spectrum were 376 nm and 3.29 eV respectively. The dispersion nature of refractive index was investigated by the single-oscillator Wemple and Di-Domenico model. Red emission was observed in the photoluminescence spectrum when excited with 376 nm. The low birefringence and high laser damage threshold (8.538 GW/cm2) values dictate the suitability of the crystal for optical devices. Z-scan studies revealed the third order nonlinear absorption coefficient (β) and refractive index (n2) of the 8HQNP crystal. The theoretical value of third order nonlinear susceptibility obtained from density function theory is good accordance with the experimental value. The frontier molecular orbital energy gap decreases with increasing external electric field in different directions which attributed to the enhancement of the second hyperpolarizability. The grown title crystal is thermally stable up to 102 °C which was identified using thermal analysis. Mechanical strength of 8HQNP was estimated by using Vicker's microhardness studies.
Energy Technology Data Exchange (ETDEWEB)
Shkir, Mohd, E-mail: shkirphysics@gmail.com [Advanced Functional Materials & Optoelectronic Laboratory (AFMOL), Physics Department, Faculty of Science, King Khalid University, Abha (Saudi Arabia); Yahia, I.S., E-mail: dr_isyahia@yahoo.com [Advanced Functional Materials & Optoelectronic Laboratory (AFMOL), Physics Department, Faculty of Science, King Khalid University, Abha (Saudi Arabia); Nano-Science & Semiconductor Labs, Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Al-Qahtani, A.M.A. [Advanced Functional Materials & Optoelectronic Laboratory (AFMOL), Physics Department, Faculty of Science, King Khalid University, Abha (Saudi Arabia)
2016-12-01
In the current work, good quality bulk size (∼32 mm × 23 mm × 10 mm) single crystals of HCl added L-alanine with well-defined morphology are successfully grown using slow evaporation technique. Crystal structure and other structural parameters were evaluated from X-ray diffraction data. Vibrational assessment of the grown crystal was done by FT-Raman analysis. The presence of chlorine and good quality of the grown crystal was confirmed by SEM/EDX analysis. Solid state UV–Vis–NIR diffused reflectance was measured and direct and indirect optical band gap was calculated using Kubelka-Munk relation and found to be 5.64 and 5 eV respectively. Dielectric measurement was carried out in high frequency range. Third order nonlinear optical susceptibility value was found to be enhanced from 1.91 × 10{sup −6} (pure) to 8.6 × 10{sup −6} esu (LAHCl). Good thermal stability of grown crystals was confirmed from DSC analysis. The enhancement in mechanical strength and crystalline perfection was also observed. - Highlights: • Bulk size (32 mm × 23 mm × 10 mm), good crystalline perfection HCl added L-alanine monocrystal is grown. • The shift in X-ray diffraction and vibrational peaks confirms the interaction of HCl. • The high optical transparency and band gap confirms its application in optoelectronic devices. • Third order NLO properties are found to be enhanced in HCl added L-alanine crystals. • The mechanical strength of the grown crystals is found to be enhanced due HCl addition.
Bancroft, Tyler D.; Hogeveen, Jeremy; Hockley, William E.; Servos, Philip
2014-01-01
In a previous study, Harris et al. (2002) found disruption of vibrotactile short-term memory after applying single-pulse transcranial magnetic stimulation (TMS) to primary somatosensory cortex (SI) early in the maintenance period, and suggested that this demonstrated a role for SI in vibrotactile memory storage. While such a role is compatible with recent suggestions that sensory cortex is the storage substrate for working memory, it stands in contrast to a relatively large body of evidence f...
Directory of Open Access Journals (Sweden)
Ineke eFengler
2015-04-01
Full Text Available Several studies have suggested that neuroplasticity can be triggered by short-term visual deprivation in healthy adults. Specifically, these studies have provided evidence that visual deprivation reversibly affects basic perceptual abilities. The present study investigated the long-lasting effects of short-term visual deprivation on emotion perception. To this aim, we visually deprived a group of young healthy adults, age-matched with a group of non-deprived controls, for 3 hours and tested them before and after visual deprivation (i.e., after 8 h on average and at 4 week follow-up on an audio-visual (i.e., faces and voices emotion discrimination task. To observe changes at the level of basic perceptual skills, we additionally employed a simple audio-visual (i.e., tone bursts and light flashes discrimination task and two unimodal (one auditory and one visual perceptual threshold measures. During the 3 h period, both groups performed a series of auditory tasks. To exclude the possibility that changes in emotion discrimination may emerge as a consequence of the exposure to auditory stimulation during the 3 h stay in the dark, we visually deprived an additional group of age-matched participants who concurrently performed unrelated (i.e., tactile tasks to the later tested abilities. The two visually deprived groups showed enhanced affective prosodic discrimination abilities in the context of incongruent facial expressions following the period of visual deprivation; this effect was partially maintained until follow-up. By contrast, no changes were observed in affective facial expression discrimination and in the basic perception tasks in any group. These findings suggest that short-term visual deprivation per se triggers a reweighting of visual and auditory emotional cues, which seem to possibly prevail for longer durations.
Yang, Yang; Yu, Haibo; York, Darrin; Cui, Qiang; Elstner, Marcus
2007-10-25
The standard self-consistent-charge density-functional-tight-binding (SCC-DFTB) method (Phys. Rev. B 1998, 58, 7260) is derived by a second-order expansion of the density functional theory total energy expression, followed by an approximation of the charge density fluctuations by charge monopoles and an effective damped Coulomb interaction between the atomic net charges. The central assumptions behind this effective charge-charge interaction are the inverse relation of atomic size and chemical hardness and the use of a fixed chemical hardness parameter independent of the atomic charge state. While these approximations seem to be unproblematic for many covalently bound systems, they are quantitatively insufficient for hydrogen-bonding interactions and (anionic) molecules with localized net charges. Here, we present an extension of the SCC-DFTB method to incorporate third-order terms in the charge density fluctuations, leading to chemical hardness parameters that are dependent on the atomic charge state and a modification of the Coulomb scaling to improve the electrostatic treatment within the second-order terms. These modifications lead to a significant improvement in the description of hydrogen-bonding interactions and proton affinities of biologically relevant molecules.
Energy Technology Data Exchange (ETDEWEB)
Trejo-Valdez, Martin, E-mail: martin.trejo@laposte.net [ESIQIE, Instituto Politécnico Nacional, México, D.F. 07738, México (Mexico); Sobral, Hugo [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Apartado Postal 70-186, México, D.F. 04510, México (Mexico); Martínez-Gutiérrez, Hugo [Centro de Nanociencias y Micro y Nanotecnologías del Instituto Politécnico Nacional, México, D.F. 07738, México (Mexico); Torres-Torres, Carlos [Sección de Estudios de Posgrado e Investigación, ESIME ZAC, Instituto Politécnico Nacional, México, D.F. 07738, México (Mexico)
2016-04-30
Zinc oxide films doped with platinum and gold nanoparticles were deposited by the spray pyrolysis technique on glass substrates. A titanium dioxide sol–gel solution containing gold and platinum aqueous ions was employed for synthesizing the nanoparticles by ultraviolet-light irradiation. The conductive properties of the samples were characterized by the electrochemical impedance spectroscopy technique. Our results showed that the impedance of zinc oxide films doped with metallic nanoparticles was, by far, lower than typical measurements in zinc oxide films. A strong enhancement in the nanosecond nonlinear optical response was also obtained in the studied metallic doped films. A vectorial two-mixing experiment performed at 532 nm and 4 ns allowed us to evaluate the sample with a third order optical nonlinearity described by approximately | χ{sub 1111}{sup (3)}| = 2.6 × 10{sup −8} esu. - Highlights: • ZnO films doped with Pt and Au nanoparticles were synthetized. • The inclusion of metallic nanoparticles in the film improves optical nonlinearities. • Conductivity of the films was enhanced by the contribution of the nanoparticles.
Li, Kang; Tang, Guodong; Kou, ShanShan; Culnane, Lance F; Zhang, Yu; Song, Yinglin; Li, Rongqing; Wei, Changmei
2015-03-15
Three complexes of M(DPIP)2 (M=Cu, Co, Zn as 1, 2, 3) were synthesized and characterized by elemental analysis, IR, UV-Vis, thermogravimetry, and X-ray diffraction. Their nonlinear optical properties were measured by the Z-scan technique and yielded a normalized transmittance of about 70% for complex 1 (45 μJ pulse), and 93% for complex 3 (68 μJ pulse at the focus point). The nonlinear absorption coefficient, β, is 1.4×10(-11) m/W for 1 and 5.6×10(-13) m/W for 3, and the third-order nonlinear refraction index, n2, is 1.0×10(-18) m(2)/W for 3. Complex 1 shows self-defocusing property, while complex 3 exhibits self-focusing property. The thermogravimetric results show that the frame structure of compounds 1-3 begin to collapse at 400, 250 and 280°C, respectively, which suggests that they elicit excellent thermal stability. This research aims to provide better understanding of these compounds, and offer preliminary explanations for the significant differences between compounds 1-3, in order to potentially help in the designing of future novel materials with NLO properties. Copyright © 2014 Elsevier B.V. All rights reserved.
Li, Kang; Tang, Guodong; Kou, ShanShan; Culnane, Lance F.; Zhang, Yu; Song, Yinglin; Li, Rongqing; Wei, Changmei
2015-03-01
Three complexes of M(DPIP)2 (M = Cu, Co, Zn as 1, 2, 3) were synthesized and characterized by elemental analysis, IR, UV-Vis, thermogravimetry, and X-ray diffraction. Their nonlinear optical properties were measured by the Z-scan technique and yielded a normalized transmittance of about 70% for complex 1 (45 μJ pulse), and 93% for complex 3 (68 μJ pulse at the focus point). The nonlinear absorption coefficient, β, is 1.4 × 10-11 m/W for 1 and 5.6 × 10-13 m/W for 3, and the third-order nonlinear refraction index, n2, is 1.0 × 10-18 m2/W for 3. Complex 1 shows self-defocusing property, while complex 3 exhibits self-focusing property. The thermogravimetric results show that the frame structure of compounds 1-3 begin to collapse at 400, 250 and 280 °C, respectively, which suggests that they elicit excellent thermal stability. This research aims to provide better understanding of these compounds, and offer preliminary explanations for the significant differences between compounds 1-3, in order to potentially help in the designing of future novel materials with NLO properties.
International Nuclear Information System (INIS)
Pramodini, S; Poornesh, P; Sudhakar, Y N; SelvaKumar, M
2014-01-01
We present the synthesis and characterization of third-order optical nonlinearity and optical limiting of the conducting polymers poly (aniline-co-o-anisidine) and poly (aniline-co-pyrrole). Nonlinear optical studies were carried out by employing the z-scan technique using a He–Ne laser operating in continuous wave mode at 633 nm. The copolymers exhibited a reverse saturable absorption process and self-defocusing properties under the experimental conditions. The estimated values of β eff , n 2 and χ (3) were found to be of the order of 10 −2 cm W −1 , 10 -5 esu and 10 −7 esu respectively. Self-diffraction rings were observed due to refractive index change when exposed to the laser beam. The copolymers possess a lower limiting threshold and clamping level, which is essential to a great extent for power limiting devices. Therefore, copolymers of aniline emerge as a potential candidate for nonlinear optical device applications. (paper)
基于三次B样条函数的SEM图像处理%SEM Image Processing Based on Third- order B- spline Function
Institute of Scientific and Technical Information of China (English)
张健
2011-01-01
SEM images, for its unique practical testing significance, need in denoising also highlight its edges and accurate edge extraction positioning, So this paper adopts a partial differential method which can maintain the edges of the denoising and a extensive application of multi - scale wavelet analysis to detect edges, all based on third - order B - spline function as the core operator, for line width test of SEM image processing, This algorithm obtained the better denoising effect and maintained edge features for SEM images.%SEM图像由于其独特的实际测试意义,需要在去噪的同时突出边缘和准确的边缘提取定位,所以提出采用能够保持边缘的偏微分方法去噪和广泛应用的多尺度小波提取边缘,基于三次B样条函数作为核心算子,对用于线宽测试的SEM图像进行处理,获得了较好的去噪并保持边缘的效果以及清晰的图像边缘检测效果.
Directory of Open Access Journals (Sweden)
Wenzhu Huang
2015-04-01
Full Text Available Static strain can be detected by measuring a cross-correlation of reflection spectra from two fiber Bragg gratings (FBGs. However, the static-strain measurement resolution is limited by the dominant Gaussian noise source when using this traditional method. This paper presents a novel static-strain demodulation algorithm for FBG-based Fabry-Perot interferometers (FBG-FPs. The Hilbert transform is proposed for changing the Gaussian distribution of the two FBG-FPs’ reflection spectra, and a cross third-order cumulant is used to use the results of the Hilbert transform and get a group of noise-vanished signals which can be used to accurately calculate the wavelength difference of the two FBG-FPs. The benefit by these processes is that Gaussian noise in the spectra can be suppressed completely in theory and a higher resolution can be reached. In order to verify the precision and flexibility of this algorithm, a detailed theory model and a simulation analysis are given, and an experiment is implemented. As a result, a static-strain resolution of 0.9 nε under laboratory environment condition is achieved, showing a higher resolution than the traditional cross-correlation method.
Minamida, Yuka; Kishi, Ryohei; Fukuda, Kotaro; Matsui, Hiroshi; Takamuku, Shota; Yamane, Masaki; Tonami, Takayoshi; Nakano, Masayoshi
2018-02-06
Tunability of the open-shell character, charge asymmetry, and third-order nonlinear optical (NLO) properties of covalently linked (hetero)phenalenyl dimers are investigated by using the density functional theory method. By changing the molecular species X and substitution position (i, j) for the linker part, a variety of intermonomer distances R and relative alignments between the phenalenyl dimers can be realized from the geometry optimizations, resulting in a wide-range tuning of diradical character y and charge asymmetry. It is found that the static second hyperpolarizabilities along the stacking direction, γ yyyy , are one-order enhanced for phenalenyl dimer systems exhibiting intermediate y, a feature that is in good agreement with the "y-γ correlation". By replacing the central carbon atoms of the phenalenyl rings with a boron or a nitrogen, we have also designed covalently linked heterophenalenyl dimers. The introduction of such a charge asymmetry to the open-shell systems, which leads to closed-shell ionic ground states, is found to further enhance the γ yyyy values of the systems having longer intermonomer distance R with intermediate ionic character, that is, charge asymmetry. The present results demonstrate a promising potential of covalently linked NLO dimers with intermediate open-shell/ionic characters as a new building block of highly efficient NLO systems. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Gnaneswara Reddy, M.
2017-09-01
This communication presents the transportation of third order hydromagnetic fluid with thermal radiation by peristalsis through an irregular channel configuration filled a porous medium under the low Reynolds number and large wavelength approximations. Joule heating, Hall current and homogeneous-heterogeneous reactions effects are considered in the energy and species equations. The Second-order velocity and energy slip restrictions are invoked. Final dimensionless governing transport equations along the boundary restrictions are resolved numerically with the help of NDsolve in Mathematica package. Impact of involved sundry parameters on the non-dimensional axial velocity, fluid temperature and concentration characteristics have been analyzed via plots and tables. It is manifest that an increasing porosity parameter leads to maximum velocity in the core part of the channel. Fluid velocity boosts near the walls of the channel where as the reverse effect in the central part of the channel for higher values of first order slip. Larger values of thermal radiation parameter R reduce the fluid temperature field. Also, an increase in heterogeneous reaction parameter Ks magnifies the concentration profile. The present study has the crucial application of thermal therapy in biomedical engineering.
Xu, Liang; Zhang, Dingfeng; Zhou, Yecheng; Zheng, Yusen; Cao, Liu; Jiang, Xiao-Fang; Lu, Fushen
2017-08-01
In this paper, mono- and di-4-N,N-bis(4-methoxylphenyl)aniline-substituted anthraquinone have been designed and synthesized through Suzuki reaction. For mono-4-N,N-bis(4-methoxylphenyl)aniline-substituted anthraquinone, polymorphous crystal structures have been obtained in different crystallization conditions. Electrochemical characterization combined with theoretical calculation suggests that the addition of a second triphenylamine unit causes a larger band gap with higher lying LUMO (Lowest Unoccupied Molecular Orbital) and HOMO (Highest Occupied Molecular Orbital). The linear optical property shows that the introduction of a second triphenylamine unit bring about a significant hyperchromic effect with the extinction coefficients increasing from 11199 M-1 cm-1 to 22136 M-1 cm-1. The third-order nonlinear optical properties indicate that the introduction of a second triphenylamine unit lead to a much larger nonlinear absorption coefficient and two-photon absorption cross section, with the relevant value increasing from 2.04 × 10-12 cm W-1 to 3.91 × 10-12 cm W-1, and from 148 GM to 286 GM, respectively.
Celani, M F S; Hurtado, R; Brandão, A H F; Maciel da Fonseca, A M R; Geber, S
2016-06-01
Objective To evaluate the effect of short-term hormone replacement therapy with tibolone 2.5 mg daily on endothelial function of healthy postmenopausal women, using flow-mediated dilation (FMD) of the brachial artery. Methods We performed a randomized, double-blinded, placebo-controlled study. A total of 100 healthy postmenopausal women were randomly allocated to receive tibolone (n = 50) or placebo (n = 50) for 28 days. Measurement of the FMD of the brachial artery was performed before and after the use of tibolone and placebo. Results A total of 31 women completed the study in the tibolone group, and 32 women completed the study in the control group. The results of the FMD measurements obtained from the women in the two groups before treatment were similar (0.018 and 0.091, for tibolone and placebo, p = 0.57). The values of the FMD in women who used tibolone and placebo, before and after the treatment, were similar in both groups. The numbers of women who presented an increase in the values of the FMD in both groups were also similar. Conclusion Our results demonstrate that the administration of 2.5 mg tibolone to healthy postmenopausal women for 28 days does not promote endothelial-dependent vasodilation, measured by FMD of the brachial artery.
International Nuclear Information System (INIS)
Law, Ying Lam E.; Dworkin, Seth B.
2016-01-01
Highlights: • Long term ground temperature response is explored using finite element methods. • Simulation method is validated against experimental and analytical data. • Temperature changes at a fast rate in the first few years and slows down gradually. • ASHRAE recommended separation distances are not always sufficient. • Thermal accumulation occurs at the centre of borehole field. - Abstract: Ground source heat pumps (GSHPs) are an environmentally friendly alternative to conventional heating and cooling systems because of their high efficiency and low greenhouse gas emissions. The ground acts as a heat sink/source for the excess/required heat inside a building for cooling and heating modes, respectively. However, imbalance in heating and cooling needs can change ground temperature over the operating duration. This increase/decrease in ground temperature lowers system efficiency and causes the ground to foul—failing to accept or provide more heat. In order to ensure that GSHPs can operate to their designed conditions, thermal modelling is required to simulate the ground temperature during system operation. In addition, the borehole field layout can have a major impact on ground temperature. In this study, four buildings were studied—a hospital, fast-food restaurant, residence, and school, each with varying borehole configurations. Boreholes were modelled in a soil volume using finite-element methods and heating and cooling fluxes were applied to the borehole walls to simulate the GSHP operation. 20 years of operation were modelled for each building for 2 × 2, 4 × 4, and 2 × 8 borehole configurations. Results indicate that the borehole separation distance of 6 m, recommended by ASHRAE, is not always sufficient to prevent borehole thermal interactions. Benefits of using a 2 × 8 configuration as opposed to a 4 × 4 configuration, which can be observed because of the larger perimeter it provides for heat to dissipate to surrounding soil were
Wojcik, E. A.; Ni, D.; Lam, T. M.; Le Coz, Y. L.
2015-07-01
We have created the first stochastic SoP (Sum-over-Paths) algorithm to extract third-order impulse-response (IR) moment within RC IC interconnects. It employs a newly discovered Feynman SoP Postulate. Importantly, our algorithm maintains computational efficiency and full parallelism. Our approach begins with generation of s-domain nodal-voltage equations. We then perform a Taylor-series expansion of the circuit transfer function. These expansions yield transition diagrams involving mathematical coupling constants, or weight factors, in integral powers of complex frequency s. Our SoP Postulate enables stochastic evaluation of path sums within the circuit transition diagram to order s3-corresponding to the order of IR moment (m3) we seek here. We furnish, for the first time, an informal algebraic proof independently validating our SoP Postulate and algorithm. We list, as well, detailed procedural steps, suitable for coding, that define an efficient stochastic algorithm for m3 IR extraction. Origins of the algorithm's statistical "capacitor-number cubed" correction and "double-counting" weight factors are explained, for completeness. Our algorithm was coded and successfully tested against exact analytical solutions for 3-, 5-, and 10-stage RC lines. We achieved better than 0.65% 1-σ error convergence, after only 10K statistical samples, in less than 1 s of 2-GHz Pentium® execution time. These results continue to suggest that stochastic SoP algorithms may find useful application in circuit analysis of massively coupled networks, such as those encountered in high-end digital IC-interconnect CAD.
Simon, P.; Semboloni, E.; van Waerbeke, L.; Hoekstra, H.; Erben, T.; Fu, L.; Harnois-Déraps, J.; Heymans, C.; Hildebrandt, H.; Kilbinger, M.; Kitching, T. D.; Miller, L.; Schrabback, T.
2015-05-01
We study the correlations of the shear signal between triplets of sources in the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) to probe cosmological parameters via the matter bispectrum. In contrast to previous studies, we adopt a non-Gaussian model of the data likelihood which is supported by our simulations of the survey. We find that for state-of-the-art surveys, similar to CFHTLenS, a Gaussian likelihood analysis is a reasonable approximation, albeit small differences in the parameter constraints are already visible. For future surveys we expect that a Gaussian model becomes inaccurate. Our algorithm for a refined non-Gaussian analysis and data compression is then of great utility especially because it is not much more elaborate if simulated data are available. Applying this algorithm to the third-order correlations of shear alone in a blind analysis, we find a good agreement with the standard cosmological model: Σ _8=σ _8(Ω _m/0.27)^{0.64}=0.79^{+0.08}_{-0.11} for a flat Λ cold dark matter cosmology with h = 0.7 ± 0.04 (68 per cent credible interval). Nevertheless our models provide only moderately good fits as indicated by χ2/dof = 2.9, including a 20 per cent rms uncertainty in the predicted signal amplitude. The models cannot explain a signal drop on scales around 15 arcmin, which may be caused by systematics. It is unclear whether the discrepancy can be fully explained by residual point spread function systematics of which we find evidence at least on scales of a few arcmin. Therefore we need a better understanding of higher order correlations of cosmic shear and their systematics to confidently apply them as cosmological probes.
Energy Technology Data Exchange (ETDEWEB)
Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1962-07-01
This report deals with numerical analysis of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. The only case treated here, in this first part, is the one when the interference term can be neglected. Programs and subroutines are thoroughly described, which determine from experimental raw data the resonant transmission, the partial areas, and the resonance parameters. (authors) [French] Le present rapport a pour objet l'analyse numerique sur ordinateur IBM 7090, des resonances dues aux neutrons 's' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode des aires partielles. Dans cette premiere partie, seul a ete envisage le cas ou le terme d'interference peut etre neglige. On y trouvera une description detaillee des programmes et sous programmes elabores pour determiner les transmissions resonantes avec leur trace, a partir des donnees experimentales brutes, les aires partielles afferentes ainsi que les parametres caracteristiques des resonances. (auteurs)
International Nuclear Information System (INIS)
Bondarev, A.L.
1993-01-01
The method of covariant calculation of the amplitudes of processes with polarized spin 1/2 particles is suggested. It can be used for calculation of interference terms in cross sections of these processes. As an illustration the expressions for the lowest order amplitudes of electron-electron scattering and for electron current with radiation of two bremsstrahlung photons in ultrarelativistic limit are presented
Prinsloo, Sarah; Novy, Diane; Driver, Larry; Lyle, Randall; Ramondetta, Lois; Eng, Cathy; Lopez, Gabriel; Li, Yisheng; Cohen, Lorenzo
2018-05-01
Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of cancer treatment and may adversely affect quality of life (QOL) for years. We explored the long-term effects of electroencephalographic neurofeedback (NFB) as a treatment for CIPN and other aspects of QOL. Seventy-one cancer survivors (mean age 62.5; 87% females) with CIPN were randomized to NFB or to a waitlist control (WLC) group. The NFB group underwent 20 sessions of NFB where rewards were given for voluntary changes in electroencephalography. Measurements of pain, cancer-related symptoms, QOL, sleep, and fatigue were obtained at baseline, end of treatment, and one and four months later. Seventy one participants enrolled in the study. At the end of treatment, 30 in the NFB group and 32 in the WLC group completed assessments; at four months, 23 in the NFB group and 28 in the WLC completed assessments. Linear mixed model analysis revealed significant group × time interaction for pain severity. A general linear model determined that the NFB group had greater improvements in worst pain (primary outcome) and other symptoms such as numbness, cancer-related symptom severity, symptom interference, physical functioning, general health, and fatigue compared with the WLC group at the end of treatment and four months (all P < 0.05). Effect sizes were moderate or large for most measures. NFB appears to result in long-term reduction in multiple CIPN symptoms and improved postchemotherapy QOL and fatigue. Copyright © 2018 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Yin, Congfei; Liang, Xiaojuan, E-mail: lxj6126@126.com; Hu, Guangcai; Hu, Xie; Chen, Xipeng; Li, Pengzhi; Xiang, Weidong, E-mail: xiangweidong001@126.com
2017-04-15
The titanate, is a material of interest for various energy applications, including photovoltaics, catalysts, and high-rate energy storage devices. Herein, its related materials, CuO/CaTi{sub 4}O{sub 9} [CCTO] thin films, were successfully fabricated on SrTiO{sub 3} (100) substrates by RF magnetron sputtering assisted with subsequent oxygen annealing. This obtained CCTO thin films were then systemically studied by X-ray powder diffraction (XRD), atomic force microscopy (AFM), scan electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). It was found that CuO and CaTi{sub 4}O{sub 9} (001) particles were closely accumulated together on the surface of the substrate in the annealing process after comparing with that of the as-prepared thin film, which was verified by SEM and AFM results. Furthermore, we investigated the third-order nonlinear optical (NLO) properties of the as-prepared and annealed CCTO thin film by means of the Z-scan technique using 650 nm femtosecond laser pulse. Post-deposition oxygen annealing was found to modify the morphological characteristics of the films, resulting in enhancing their NLO properties. The observation of NLO performance of annealed CCTO thin film indicates that RF magnetron sputtering is a feasible method for the fabrication of optical thin films, which can be expanded to fabricate other NLO materials from the corresponding dispersions. Naturally, we concluded that the CCTO thin film occupy a better NLO property, and thus enlarge its application in nonlinear optics. - Highlights: • The CCTO thin film was prepared using the RF magnetron sputtering and oxygen annealing. • The film was prepared on the SrTiO{sub 3}(100) substrates with a Ca{sub 2}CuO{sub 3} target. • The oxygen annealing was found can effectively enhance the film quality and NLO property. • The film was characterized using XPS, SEM, AFM, TEM, XRD and Z-scan techniques.
Cioffi, Iacopo; Farella, Mauro; Festa, Paola; Martina, Roberto; Palla, Sandro; Michelotti, Ambrosina
2015-01-01
To investigate the effects of the application of an acute alteration of the occlusion (ie, interference) on the habitual masseter electromyographic (EMG) activity of females with temporomandibular disorders (TMD)-related muscular pain during wakefulness. Seven female volunteers with masticatory myofascial pain participated in a crossover randomized clinical trial. Gold foils were glued on an occlusal contact area (active occlusal interference, AI) or on the vestibular surface of the same molar (dummy interference, DI) and left for 8 days. The masseter electromyogram was recorded during wakefulness in the natural environment by portable recorders under interference-free, dummy-interference, and active-interference conditions. The number, amplitude, and duration of EMG signal fractions with amplitudes above 10% of the maximum voluntary contraction (activity periods, APs) were computed in all experimental conditions. Muscle pain, headache, and perceived stress were each assessed with a visual analog scale (VAS), and an algometer was used to assess masseter and temporalis pressure pain thresholds. Data were analyzed by means of analysis of variance. The frequency and duration of the recorded APs did not differ significantly between the experimental conditions (P>.05), but a small and significant reduction of the EMG mean amplitude of the APs occurred with AI (P.05). An active occlusal interference in female volunteers with masticatory muscle pain had little influence on the masseter EMG activity pattern during wakefulness and did not affect the pressure tenderness of the masseter and temporalis.
Communications in interference limited networks
2016-01-01
This book offers means to handle interference as a central problem of operating wireless networks. It investigates centralized and decentralized methods to avoid and handle interference as well as approaches that resolve interference constructively. The latter type of approach tries to solve the joint detection and estimation problem of several data streams that share a common medium. In fact, an exciting insight into the operation of networks is that it may be beneficial, in terms of an overall throughput, to actively create and manage interference. Thus, when handled properly, "mixing" of data in networks becomes a useful tool of operation rather than the nuisance as which it has been treated traditionally. With the development of mobile, robust, ubiquitous, reliable and instantaneous communication being a driving and enabling factor of an information centric economy, the understanding, mitigation and exploitation of interference in networks must be seen as a centrally important task.
Energy Technology Data Exchange (ETDEWEB)
Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1963-07-01
This report deals with the numerical analysis on an I.B.M. 7090 computer of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. In this second part the interference term is taken into account. Modifications have been made in the programs and subroutines described in the first part, to determine the resonant transmissions from experimental raw data, and the relating partial areas. Also programs and subroutines are thoroughly described, which estimate the resonance parameters. The field of the partial area method has been extended to cover the case where several resonances have to be treated simultaneously, provided they do not interfere. (authors) [French] Le pretent rapport a pour objet l'analyse numerique sur ordinateur I.B.M. 7090 des resonances dues aux neutrons ''s'' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode dea aires partielles. Dans cette deuxieme partie il a ete tenu compte du terme d'interference. On y trouvera une description des amenagements apportes aux programmes et sous-programmes decrits dans la premiere partie pour determiner les transmissions interfero-resonnantes a partir des donnees experimentales brutes et les aires partielles afferentes. Sont egalement decrits les programmes et sous-programmes necessaires au calcul des parametres caracteristiques des resonances. Le domaine d'application de la methode a ete etendu au traitement simultane de plusieurs resonances groupees n'interferant pas entre elles. (auteurs)
DEFF Research Database (Denmark)
Jørgensen, Jacob Lykkebo; Gagliardi, Alessio; Pecchia, Alessandro
2014-01-01
Destructive quantum interference in single molecule electronics is an intriguing phenomenon; however, distinguishing quantum interference effects from generically low transmission is not trivial. In this paper, we discuss how quantum interference effects in the transmission lead to either low...... suppressed when quantum interference effects dominate. That is, we expand the understanding of propensity rules in inelastic electron tunneling spectroscopy to molecules with destructive quantum interference....
Ren, Zhengyong; Zhong, Yiyuan; Chen, Chaojian; Tang, Jingtian; Kalscheuer, Thomas; Maurer, Hansruedi; Li, Yang
2018-03-01
During the last 20 years, geophysicists have developed great interest in using gravity gradient tensor signals to study bodies of anomalous density in the Earth. Deriving exact solutions of the gravity gradient tensor signals has become a dominating task in exploration geophysics or geodetic fields. In this study, we developed a compact and simple framework to derive exact solutions of gravity gradient tensor measurements for polyhedral bodies, in which the density contrast is represented by a general polynomial function. The polynomial mass contrast can continuously vary in both horizontal and vertical directions. In our framework, the original three-dimensional volume integral of gravity gradient tensor signals is transformed into a set of one-dimensional line integrals along edges of the polyhedral body by sequentially invoking the volume and surface gradient (divergence) theorems. In terms of an orthogonal local coordinate system defined on these edges, exact solutions are derived for these line integrals. We successfully derived a set of unified exact solutions of gravity gradient tensors for constant, linear, quadratic and cubic polynomial orders. The exact solutions for constant and linear cases cover all previously published vertex-type exact solutions of the gravity gradient tensor for a polygonal body, though the associated algorithms may differ in numerical stability. In addition, to our best knowledge, it is the first time that exact solutions of gravity gradient tensor signals are derived for a polyhedral body with a polynomial mass contrast of order higher than one (that is quadratic and cubic orders). Three synthetic models (a prismatic body with depth-dependent density contrasts, an irregular polyhedron with linear density contrast and a tetrahedral body with horizontally and vertically varying density contrasts) are used to verify the correctness and the efficiency of our newly developed closed-form solutions. Excellent agreements are obtained
Energy Technology Data Exchange (ETDEWEB)
Nivetha, K. [Centre for Crystal Growth, School of Advanced Sciences, VIT University, Vellore 632 014 (India); Kalainathan, S., E-mail: kalainathan@yahoo.com [Centre for Crystal Growth, School of Advanced Sciences, VIT University, Vellore 632 014 (India); Yamada, M. [Research Center for Engineering Science, Graduate School of Engineering Science, Akita University, 1-1 Tegatagakuen-machi, Akita 010-8502 (Japan); Kondo, Y. [Department of Life Science, Graduate School of Engineering Science, Akita University, 1-1 Tegatagakuen-machi, Akita 010-8502 (Japan); Hamada, F. [Department of Applied Chemistry, Graduate School of Engineering Science, Akita University, 1-1 Tegatagakuen-machi, Akita 010-8502 (Japan)
2017-02-15
A new organic stilbazolium derivative, 1-Ethyl-2-(2-p-tolyl-vinyl)-pyridinium iodide (TASI), was grown from methanol:acetonitrile (1:3) mixed solvent by slow evaporation technique. Single crystal X-ray diffraction analysis revealed that TASI crystallizes in triclinic system with a centrosymmetric space group P-1. The molecular structure and the presence of expected functional groups of TASI were confirmed by {sup 1}H NMR and FT-IR spectroscopic studies. The HOMO and LUMO energies influence the charge transfer takes place within the molecule. The grown crystal was thermally stable up to 210 °C as determined by TG/DTA analysis. UV-Vis-NIR spectral study showed that the grown crystal was transparent in the wavelength range of 438–1100 nm. Mechanical behaviour and surface laser damage threshold were studied to find the suitability of the grown crystal for device fabrication. Studies of its third-order nonlinear optical properties using a Z-scan technique demonstrates that TASI crystal is capable of exhibiting reverse saturable absorption and self-focusing performance with the second-order molecular hyperpolarizability (γ) 4.983 × 10{sup −34} esu. The third-order nonlinear susceptibility of TASI was found to be 8.931 × 10{sup −6} esu, which is higher than a few other stilbazolium derivative crystals. - Highlights: • TASI is a new organic stilbazolium derivative and was grown by slow evaporation technique. • HOMO-LUMO analysis helps to explain charge transfer interaction within the molecule. • The grown crystal has 80% transmittance in the visible and near-IR spectral range. • Thermally, electrically and mechanically efficient for NLO applications. • Z-scan measurements reveal the aptness of the grown crystal for third order NLO applications.
The intention interference effect.
Cohen, Anna-Lisa; Kantner, Justin; Dixon, Roger A; Lindsay, D Stephen
2011-01-01
Intentions have been shown to be more accessible (e.g., more quickly and accurately recalled) compared to other sorts of to-be-remembered information; a result termed an intention superiority effect (Goschke & Kuhl, 1993). In the current study, we demonstrate an intention interference effect (IIE) in which color-naming performance in a Stroop task was slower for words belonging to an intention that participants had to remember to carry out (Do-the-Task condition) versus an intention that did not have to be executed (Ignore-the-Task condition). In previous work (e.g., Cohen et al., 2005), having a prospective intention in mind was confounded with carrying a memory load. In Experiment 1, we added a digit-retention task to control for effects of cognitive load. In Experiment 2, we eliminated the memory confound in a new way, by comparing intention-related and control words within each trial. Results from both Experiments 1 and 2 revealed an IIE suggesting that interference is very specific to the intention, not just to a memory load.
Third Order Susceptibility of Platinum Sulfide Sol
National Research Council Canada - National Science Library
LaiHing, Kenneth
1992-01-01
.... Experimentally this is determined using degenerate four-wave mixing (DFWM). Pure sulfur sol was prepared by dissolving the solid sulfur in hydrazine, followed by addition of distilled water with vigorous stirring...
Energy Technology Data Exchange (ETDEWEB)
Delfin L, A.; Alonso V, G. [ININ, Km. 36.5 Carretera Mexico-Toluca, 52045 Ocoyocac, Estado de Mexico (Mexico); Valle G, E. del [IPN-ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: adl@nuclear.inin.mx
2003-07-01
In this work two nodal schemes of finite element are presented, one of second and the other of third order of accurate that allow to determine the radial distribution of power starting from the corresponding reactivities.The schemes here developed were obtained taking as starting point the equation developed by Driscoll et al, the one which is based on the diffusion approach of 1-1/2 energy groups. This equation relates the power fraction of an assemble with their reactivity and with the power fractions and reactivities of the assemblies that its surround it. Driscoll and collaborators they solve in form approximate such equation supposing that the reactivity of each assemble it is but a lineal function of the burnt one of the fuel. The spatial approach carries out it with the classic technique of finite differences centered in mesh. Nevertheless that the algebraic system to which its arrive it can be solved without more considerations introduce some additional suppositions and adjustment parameters that it allows them to predict results comparable to those contributed by three dimensions analysis and this way to reduce the one obtained error when its compare their results with those of a production code like CASMO. Also in the two schemes that here are presented the same approaches of Driscoll were used being obtained errors of the one 10% and of 5% for the second schemes and third order respectively for a test case that it was built starting from data of the Cycle 1 of the Unit 1 of the Laguna Verde Nucleo electric plant. These errors its were obtained when comparing with a computer program based on the matrix response method. It is sought to have this way a quick and efficient tool for the multicycle analysis in the fuel management. However, this model presents problems in the appropriate prediction of the average burnt of the nucleus and of the burnt one by lot. (Author)
Directory of Open Access Journals (Sweden)
Thadeu Keller Filho
2006-09-01
Full Text Available O objetivo deste trabalho foi verificar se as ocorrências de dias secos e chuvosos são condicionalmente dependentes da seqüência dos três dias secos e chuvosos anteriores, numa zona pluviometricamente homogênea, por meio da cadeia não-homogênea de Markov de terceira ordem. Os resultados mostraram que as probabilidades diárias de transição podem ser adequadamente estimadas, com base em dados agregados bimestralmente, seguidas de interpolação por meio de funções sinusoidais. Além disso, evidenciou-se que, naquela zona, as ocorrências diárias de chuva são condicionalmente dependentes da seqüência de dias secos e chuvosos nos três dias anteriores. A cadeia não-homogênea de Markov de terceira ordem é um importante instrumento para a análise da dependência entre as seqüências de dias secos e chuvosos em determinadas regiões.The aim of this work was to verify if the occurrence of dry and wet days are conditionally dependent on the sequences of the dry and wet three preceding days, in a rainfall homogeneous area, using the nonhomogeneous third-order Markov chains. The results showed that daily transition probabilities can be properly estimated from two-month aggregate data, and then adjusted by means of sinusoidal functions. Besides, it was evidenced that everyday rain events in that area are conditionally dependent on the sequences of the dry and wet three days previous to occurrences. The third-order nonhomogeneous Markov chains are an important instrument for the analysis of the dependence between sequences of dry and wet days in certain areas.
Energy Technology Data Exchange (ETDEWEB)
Delfin L, A.; Alonso V, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Valle G, E. del [IPN-ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: adl@nuclear.inin.mx
2003-07-01
In this work the development of a third order scheme of finite differences centered in mesh is presented and it is applied in the numerical solution of those diffusion equations in multi groups in stationary state and X Y geometry. Originally this scheme was developed by Hennart and del Valle for the monoenergetic diffusion equation with a well-known source and they show that the one scheme is of third order when comparing the numerical solution with the analytical solution of a model problem using several mesh refinements and boundary conditions. The scheme by them developed it also introduces the application of numeric quadratures to evaluate the rigidity matrices and of mass that its appear when making use of the finite elements method of Galerkin. One of the used quadratures is the open quadrature of 4 points, no-standard, of Newton-Cotes to evaluate in approximate form the elements of the rigidity matrices. The other quadrature is that of 3 points of Radau that it is used to evaluate the elements of all the mass matrices. One of the objectives of these quadratures are to eliminate the couplings among the Legendre moments 0 and 1 associated to the left and right faces as those associated to the inferior and superior faces of each cell of the discretization. The other objective is to satisfy the particles balance in weighed form in each cell. In this work it expands such development to multiplicative means considering several energy groups. There are described diverse details inherent to the technique, particularly those that refer to the simplification of the algebraic systems that appear due to the space discretization. Numerical results for several test problems are presented and are compared with those obtained with other nodal techniques. (Author)
Lloyd-Jones, Toby J; Nakabayashi, Kazuyo
2014-01-01
Using a novel paradigm to engage the long-term mappings between object names and the prototypical colors for objects, we investigated the retrieval of object-color knowledge as indexed by long-term priming (the benefit in performance from a prior encounter with the same or a similar stimulus); a process about which little is known. We examined priming from object naming on a lexical-semantic matching task. In the matching task participants encountered a visually presented object name (Experiment 1) or object shape (Experiment 2) paired with either a color patch or color name. The pairings could either match whereby both were consistent with a familiar object (e.g., strawberry and red) or mismatch (strawberry and blue). We used the matching task to probe knowledge about familiar objects and their colors pre-activated during object naming. In particular, we examined whether the retrieval of object-color information was modality-specific and whether this influenced priming. Priming varied with the nature of the retrieval process: object-color priming arose for object names but not object shapes and beneficial effects of priming were observed for color patches whereas inhibitory priming arose with color names. These findings have implications for understanding how object knowledge is retrieved from memory and modified by learning.
Directory of Open Access Journals (Sweden)
Toby Jonathan Lloyd-Jones
2014-06-01
Full Text Available Using a novel paradigm to engage the long-term mappings between object names and the prototypical colours for objects, we investigated the retrieval of object-colour knowledge as indexed by long-term priming (the benefit in performance from a prior encounter with the same or a similar stimulus; a process about which little is known. We examined priming from object naming on a lexical-semantic matching task. In the matching task participants encountered a visually presented object name (Experiment 1 or object shape (Experiment 2 paired with either a colour patch or colour name. The pairings could either match whereby both were consistent with a familiar object (e.g., strawberry and red or mismatch (strawberry and blue. We used the matching task to probe knowledge about familiar objects and their colours pre-activated during object naming. In particular, we examined whether the retrieval of object-colour information was modality-specific and whether this influenced priming. Priming varied with the nature of the retrieval process: object-colour priming arose for object names but not object shapes and beneficial effects of priming were observed for colour patches whereas inhibitory priming arose with colour names. These findings have implications for understanding how object knowledge is retrieved from memory and modified by learning.
DEFF Research Database (Denmark)
Del Nobile, Eugenio; Kouvaris, Christoforos; Sannino, Francesco
2012-01-01
We study different patterns of interference in WIMP-nuclei elastic scattering that can accommodate the DAMA and CoGeNT experiments via an isospin violating ratio $f_n/f_p=-0.71$. We study interference between the following pairs of mediators: Z and Z', Z' and Higgs, and two Higgs fields. We show ...
Short-Term Forgetting without Interference
McKeown, Denis; Mercer, Tom
2012-01-01
In the 1st reported experiment, we demonstrate that auditory memory is robust over extended retention intervals (RIs) when listeners compare the timbre of complex tones, even when active or verbal rehearsal is difficult or impossible. Thus, our tones have an abstract timbre that resists verbal labeling, they differ across trials so that no…
Directory of Open Access Journals (Sweden)
Y. W. Sun
2013-08-01
Full Text Available In this paper, we present an optimized analysis algorithm for non-dispersive infrared (NDIR to in situ monitor stack emissions. The proposed algorithm simultaneously compensates for nonlinear absorption and cross interference among different gases. We present a mathematical derivation for the measurement error caused by variations in interference coefficients when nonlinear absorption occurs. The proposed algorithm is derived from a classical one and uses interference functions to quantify cross interference. The interference functions vary proportionally with the nonlinear absorption. Thus, interference coefficients among different gases can be modeled by the interference functions whether gases are characterized by linear or nonlinear absorption. In this study, the simultaneous analysis of two components (CO2 and CO serves as an example for the validation of the proposed algorithm. The interference functions in this case can be obtained by least-squares fitting with third-order polynomials. Experiments show that the results of cross interference correction are improved significantly by utilizing the fitted interference functions when nonlinear absorptions occur. The dynamic measurement ranges of CO2 and CO are improved by about a factor of 1.8 and 3.5, respectively. A commercial analyzer with high accuracy was used to validate the CO and CO2 measurements derived from the NDIR analyzer prototype in which the new algorithm was embedded. The comparison of the two analyzers show that the prototype works well both within the linear and nonlinear ranges.
Interference-exact radiative transfer equation
DEFF Research Database (Denmark)
Partanen, Mikko; Haÿrynen, Teppo; Oksanen, Jani
2017-01-01
Maxwell's equations with stochastic or quantum optical source terms accounting for the quantum nature of light. We show that both the nonlocal wave and local particle features associated with interference and emission of propagating fields in stratified geometries can be fully captured by local damping...... and scattering coefficients derived from the recently introduced quantized fluctuational electrodynamics (QFED) framework. In addition to describing the nonlocal optical interference processes as local directionally resolved effects, this allows reformulating the well known and widely used radiative transfer...... equation (RTE) as a physically transparent interference-exact model that extends the useful range of computationally efficient and quantum optically accurate interference-aware optical models from simple structures to full optical devices....
Cognitive interference management in heterogeneous networks
Marabissi, Dania
2015-01-01
This brief investigates the role of interference management in Heterogeneous Networks (Het Nets), focusing on cognitive approaches and the use of beamforming. Key concepts of Het Nets are introduced and different deployment strategies are examined, such as sharing the same frequency band of the macro cells or using new high frequency bands. Particular attention is devoted to co-channel deployment and to the problem of interference management, addressing various strategies that can be adopted to handle the interference between the cells. In addition, the brief explores cognitive small cells which are able to avoid or limit interference by using suitable beamforming and resource allocation schemes. The suggested solutions are supported by numerical results in terms of performance evaluations and comparisons.
Assessment of life interference in anxious children
DEFF Research Database (Denmark)
Rapee, Ronald; Thastum, Mikael; Chavira, Denise
associated with mental disorders arguably the key issue of relevance to both sufferers and therapists. Yet among both childhood and adult disorders the primary focus in terms of assessment and treatment is on symptoms, with far less attention paid to the impact of these symptoms on the sufferer's life....... This imbalance has particularly characterised research on child anxiety where few studies have examined either the impact of anxiety disorders on children's lives or the effects of treatments on life interference. To some extent this lack of attention has come from a lack of well developed measures to assess...... life interference derived from symptoms of anxiety. Broader and more general life interference measures tend to have minimal relevance for children with anxiety disorders. The current paper will describe two measures of life interference that have been developed at the Centre for Emotional Health...
Jayaprakash, P.; Sangeetha, P.; Kumari, C. Rathika Thaya; Caroline, M. Lydia
2017-08-01
A nonlinear optical bulk single crystal of L-methionine admixtured D-mandelic acid (LMDMA) has been grown by slow solvent evaporation technique using water as solvent at ambient temperature. The crystallized LMDMA single crystal subjected to single crystal X-ray diffraction study confirmed monoclinic system with the acentric space group P21. The FTIR analysis gives information about the modes of vibration in the various functional groups present in LMDMA. The UV-visible spectral analysis assessed the optical quality and linear optical properties such as extinction coefficient, reflectance, refractive index and from which optical conductivity and electric susceptibility were also evaluated. The frequency doubling efficiency was observed using Kurtz Perry powder technique. A multiple shot laser was utilized to evaluate the laser damage threshold energy of the crystal. Discrete thermodynamic properties were carried out by TG-DTA studies. The hardness, Meyer's index, yield strength, elastic stiffness constant, Knoop hardness, fracture toughness and brittleness index were analyzed using Vickers microhardness tester. Layer growth pattern and the surface defect were examined by chemical etching studies using optical microscope. Fluorescence emission spectrum was recorded and lifetime was also studied. The electric field response of crystal was investigated from the dielectric studies at various temperatures at different frequencies. The third-order nonlinear optical response in LMDMA has been investigated using Z-scan technique with He-Ne laser at 632.8 nm and nonlinear parameters such as refractive index (n2), absorption coefficient (β) and susceptibility (χ3) investigated extensively for they are in optical phase conjucation, high-speed optical switches and optical dielectric devices.
Yuvaraj, S.; Manikandan, N.; Vinitha, G.
2017-11-01
Mn0.55Cu0.45Fe2O4 nanoparticles were synthesized by wet chemical co-precipitation method. The obtained samples were annealed at different temperatures (500 °C to 1250 °C). All annealed samples were characterized for their structural, magnetic, linear and non-linear optical properties. XRD results confirm single phase cubic spinel structure only for samples annealed at 800 °C and 1250 °C. The average crystallite sizes of the samples are in the range of 11-37 nm. HR-SEM image of the sample annealed at 800 °C exposed spherical morphology. The quantitative analysis of EDX results is close to the expected values. Bandgaps were evaluated from UV-DRS. The FTIR spectrum showing the essential peaks around 452.1 and 567.2 cm-1 prove the formation of spinel nanoparticles. In PL spectrum, a broad emission peak is attained in visible region at 485 nm. The saturation magnetization (M s), coercivity (H c) and remanence magnetization (M r) are obtained from the hysteresis curve. Nonlinear absorption coefficients (10-4 cm W-1), nonlinear indices of refraction (10-8 cm2 W-1) and the third order nonlinear susceptibilities (10-6 esu) are determined using Z-scan experiment. CW laser beam is utilized to study the optical limiting characteristics and the results prove these materials to be a potential candidate for device applications like optical switches and power limiters.
Mitigation of MIMO Co-Channel Interference using robust interference cancellation receiver
DEFF Research Database (Denmark)
Rahman, Muhammad Imadur; De Carvalho, Elisabeth; Prasad, Ramjee
2007-01-01
(STBC) link may become equivalent to an interfering Spatial Multiplexing (SM) link. Using this knowledge and understanding, we propose an interference cancellation receiver robust to different types of MIMO interferers at cell edge for the Downlink (DL) of cellular systems. The receiver systematically...... performs a multiple symbol processing: this is the appropriate processing when the signal of interest or the signal of interferer is correlated across symbols, which is the case for STBC transmission. We evaluated different link combinations in terms of Signal to Interference and Noise Ratio (SINR......) statistics and Bit Error Rate (BER) performance in cellular Orthogonal Frequency Division Multiple Access (OFDMA) systems. We have found that the proposed multiple-symbol linear interference cancellation receiver performs satisfactorily when any kind of single 'logical' stream MIMO scheme is present...
Interference and Sensitivity Analysis.
VanderWeele, Tyler J; Tchetgen Tchetgen, Eric J; Halloran, M Elizabeth
2014-11-01
Causal inference with interference is a rapidly growing area. The literature has begun to relax the "no-interference" assumption that the treatment received by one individual does not affect the outcomes of other individuals. In this paper we briefly review the literature on causal inference in the presence of interference when treatments have been randomized. We then consider settings in which causal effects in the presence of interference are not identified, either because randomization alone does not suffice for identification, or because treatment is not randomized and there may be unmeasured confounders of the treatment-outcome relationship. We develop sensitivity analysis techniques for these settings. We describe several sensitivity analysis techniques for the infectiousness effect which, in a vaccine trial, captures the effect of the vaccine of one person on protecting a second person from infection even if the first is infected. We also develop two sensitivity analysis techniques for causal effects in the presence of unmeasured confounding which generalize analogous techniques when interference is absent. These two techniques for unmeasured confounding are compared and contrasted.
Binaural Interference: Quo Vadis?
Jerger, James; Silman, Shlomo; Silverman, Carol; Emmer, Michele
2017-04-01
The reality of the phenomenon of binaural interference with speech recognition has been debated for two decades. Research has taken one of two avenues; group studies or case reports. In group studies, a sample of the elderly population is tested on speech recognition under three conditions; binaural, monaural right and monaural left. The aim is to determine the percent of the sample in which the expected outcome (binaural score-better-than-either-monaural score) is reversed (i.e., one of the monaural scores is better than the binaural score). This outcome has been commonly used to define binaural interference. The object of group studies is to answer the "how many" question, what is the prevalence of binaural interference in the sample. In case reports the binaural interference conclusion suggested by the speech recognition tests is not accepted until it has been corroborated by other independent diagnostic audiological measures. The aim is to attempt to determine the basis for the findings, to answer the "why" question. This article is at once tutorial, editorial and a case report. We argue that it is time to accept the reality of the phenomenon of binaural interference, to eschew group statistical approaches in search of an answer to the "how many" question, and to focus on individual case reports in search of an answer to the "why" question. American Academy of Audiology.
Christensen, L V; Rassouli, N M
1995-11-01
In 12 subjects, a pliable, yet unbreakable, intercuspal interference (aluminum shim onlay splint; uniform height of 0.25 mm) was placed between either the right or left maxillary and mandibular second premolars and first molars. During brief and forceful biting (dynamic chewing stroke of about 20 kg force) the interference emulated a semisoft food bolus, and at the end of biting (subsequent static clenching stroke of about 20 kg force) it emulated a rigid metal interference. During dynamic/static biting, rotational electrognathography measured maximum frontal and horizontal plane torque of the right and left mandibular condyles. Eleven subjects (92%) showed frontal plane upward rotation (mean of 1.0 degree) of the condyle contralateral to the interference, and one subject (8%) showed frontal plane upward rotation (0.4 degree) of the condyle ipsilateral to the interference. Two subjects (17%) showed no horizontal plane rotation; seven subjects (58%) showed backward rotation (mean of 0.4 degree) of the condyle contralateral to the interference; and three subjects (25%) showed backward rotation (mean of 0.3 degree) of the condyle ipsilateral to the interference. It is suggested that, in the presence of an occlusal interference, mastication may have both short- and long-term detrimental effects.
Generalized Multiphoton Quantum Interference
Directory of Open Access Journals (Sweden)
Max Tillmann
2015-10-01
Full Text Available Nonclassical interference of photons lies at the heart of optical quantum information processing. Here, we exploit tunable distinguishability to reveal the full spectrum of multiphoton nonclassical interference. We investigate this in theory and experiment by controlling the delay times of three photons injected into an integrated interferometric network. We derive the entire coincidence landscape and identify transition matrix immanants as ideally suited functions to describe the generalized case of input photons with arbitrary distinguishability. We introduce a compact description by utilizing a natural basis that decouples the input state from the interferometric network, thereby providing a useful tool for even larger photon numbers.
International Nuclear Information System (INIS)
Chapman, R.S.
1998-01-01
Interfering factors are evident in both limited reagent (radioimmunoassay) and excess reagent (immunometric assay) technologies and should be suspected whenever there is a discrepancy between analytical results and clinical findings in the investigation of particular diseases. The overall effect of interference in immunoassay is analytical bias in result, either positive or negative of variable magnitude. The interference maybe caused by a wide spectrum of factors from poor sample collection and handling to physiological factors e.g. lipaemia, heparin treatment, binding protein abnormalities, autoimmunity and drug treatments. The range of interfering factors is extensive and difficult to discuss effectively in a short review
Krishnakumar, M.; Karthick, S.; Thirupugalmani, K.; Babu, B.; Vinitha, G.
2018-05-01
In present investigation, single crystals of organic charge transfer complex, 2-amino-4-methyl pyridinium-4-methoxy benzoate (2A4MP4MB) was grown by controlled slow evaporation solution growth technique using methanol as a solvent at room temperature. Single crystal XRD analysis confirmed the crystal system and lattice parameters of 2A4MP4MB. The crystalline nature, presence of various vibrational modes and other chemical bonds in the compound have been recognized and confirmed by powder X-ray diffraction, FT-IR and FT-Raman spectroscopic techniques respectively. The presence of various proton and carbon positions in title compound was confirmed using 1H NMR and 13C NMR spectral studies. The wide optical operating window and cut-off wavelength were identified and band gap value of the title compound was calculated using UV-vis-NIR study. The specific heat capacity (cp) values of the title compound, 1.712 J g-1·K-1 at 300 K and 13.6 J g-1 K-1 at 433 K (melting point) were measured using Modulated Differential Scanning Calorimetric studies (MDSC). From Z-scan study, nonlinear refractive index (n2), nonlinear absorption (β) and third order nonlinear susceptibility (χ(3)) values were determined. The self-defocusing effect and saturable absorption behavior of the material were utilized to exhibit the optical limiting action at λ = 532 nm by employing the same continuous wave (cw) Nd: YAG laser source. The laser damage threshold (LDT) study of title compound was carried out using Nd: YAG laser of 532 nm wavelength. The Vickers' micro hardness test was carried out at room temperature and obtained results were investigated using classical Meyer's law. In addition, DFT calculations were carried out for the first time for this compound. These characterization studies performed on the title compound planned to probe the valuable and safe region of optical, thermal and mechanical properties to improve efficacy of 2A4MP4MB single crystals in optoelectronic device
Laser Interference Lithography
van Wolferen, Hendricus A.G.M.; Abelmann, Leon; Hennessy, Theodore C.
In this chapter we explain how submicron gratings can be prepared by Laser Interference Lithography (LIL). In this maskless lithography technique, the standing wave pattern that exists at the intersection of two coherent laser beams is used to expose a photosensitive layer. We show how to build the
Czech Academy of Sciences Publication Activity Database
Peřina, Jan
2003-01-01
Roč. 48, č. 4 (2003), s. 99-103 ISSN 0447-6441 R&D Projects: GA MŠk LN00A015 Institutional research plan: CEZ:AV0Z1010921 Keywords : interference * quantum cryptography * quantum computing * quantum teleportation Subject RIV: BH - Optics, Masers, Lasers
BUILDUP OF PROACTIVE INTERFERENCE IN JAPANESE KANJI LEARNING
FUJITA, Tadashi
1995-01-01
The discriminative assumption on buildup of proactive interference in short-term memory predicts that when intertrial similarity of items is high, the proactive interference is built up while interlist similarity of items is low, the proactive interference is not built up. To test the discriminative assumption in Japanese Kanji learning, intertrial similarity was changed by the acoustic, the radical (as one of the figurative properties), and the radical plus semantic properties in Kanji. For ...
Codebook-based interference alignment for uplink MIMO interference channels
Lee, Hyun Ho
2014-02-01
In this paper, we propose a codebook-based interference alignment (IA) scheme in the constant multiple-input multipleoutput (MIMO) interference channel especially for the uplink scenario. In our proposed scheme, we assume cooperation among base stations (BSs) through reliable backhaul links so that global channel knowledge is available for all BSs, which enables BS to compute the transmit precoder and inform its quantized index to the associated user via limited rate feedback link.We present an upper bound on the rate loss of the proposed scheme and derive the scaling law of the feedback load tomaintain a constant rate loss relative to IA with perfect channel knowledge. Considering the impact of overhead due to training, cooperation, and feedback, we address the effective degrees of freedom (DOF) of the proposed scheme and derive the maximization of the effective DOF. From simulation results, we verify our analysis on the scaling law to preserve the multiplexing gain and confirm that the proposed scheme is more effective than the conventional IA scheme in terms of the effective DOF. © 2014 KICS.
A model for interference and forgetting
Raaijmakers, J.G.W.; Mensink, G.J.M.A
1988-01-01
A new model for interference and forgetting is presented. The model is based on the search of associative memory (SAM) theory for retrieval from long-term memory by J. G. Raaijmakers and R. M. Shiffrin, see record 1981-20491-001). It includes a contextual fluctuation process that enables it to
Codebook-based interference alignment for uplink MIMO interference channels
Lee, Hyun Ho; Park, Kihong; Ko, Youngchai; Alouini, Mohamed-Slim
2014-01-01
In this paper, we propose a codebook-based interference alignment (IA) scheme in the constant multiple-input multipleoutput (MIMO) interference channel especially for the uplink scenario. In our proposed scheme, we assume cooperation among base
Electromagnetic interference: a radiant future!
Leferink, Frank Bernardus Johannes
2015-01-01
Although Electromagnetic Interference and Electromagnetic Compatibility are well established domains, the introduction of new technologies results in new challenges. Changes in both measurement techniques, and technological trends resulting in new types of interference are described. These are the
Autonomy, Competence and Non-interference.
Roberts, Joseph T F
2017-12-30
In light of the variety of uses of the term autonomy in recent bioethics literature, in this paper, I suggest that competence, not being as contested, is better placed to play the anti-paternalistic role currently assigned to autonomy. The demonstration of competence, I will argue, can provide individuals with robust spheres of non-interference in which they can pursue their lives in accordance with their own values. This protection from paternalism is achieved by granting individuals rights to non-interference upon demonstration of competence. In this paper, I present a risk-sensitive account of competence as a means of grounding rights to non-interference. On a risk-sensitive account of competence individuals demonstrate their competence by exercising three capacities to the extent necessary to meet a threshold determined by the riskiness of the decision. These three capacities are the capacity to (i) acquire knowledge, (ii) use instrumental rationality, and (iii) form and revise a life plan.
A homology sound-based algorithm for speech signal interference
Jiang, Yi-jiao; Chen, Hou-jin; Li, Ju-peng; Zhang, Zhan-song
2015-12-01
Aiming at secure analog speech communication, a homology sound-based algorithm for speech signal interference is proposed in this paper. We first split speech signal into phonetic fragments by a short-term energy method and establish an interference noise cache library with the phonetic fragments. Then we implement the homology sound interference by mixing the randomly selected interferential fragments and the original speech in real time. The computer simulation results indicated that the interference produced by this algorithm has advantages of real time, randomness, and high correlation with the original signal, comparing with the traditional noise interference methods such as white noise interference. After further studies, the proposed algorithm may be readily used in secure speech communication.
Neural mechanisms of proactive interference-resolution.
Nee, Derek Evan; Jonides, John; Berman, Marc G
2007-12-01
The ability to mitigate interference from information that was previously relevant, but is no longer relevant, is central to successful cognition. Several studies have implicated left ventrolateral prefrontal cortex (VLPFC) as a region tied to this ability, but it is unclear whether this result generalizes across different tasks. In addition, it has been suggested that left anterior prefrontal cortex (APFC) also plays a role in proactive interference-resolution although support for this claim has been limited. The present study used event-related functional magnetic resonance imaging (fMRI) to investigate the role of these regions in resolving proactive-interference across two different tasks performed on the same subjects. Results indicate that both left VLPFC and left APFC are involved in the resolution of proactive interference across tasks. However, different functional networks related to each region suggest dissociable roles for the two regions. Additionally, regions of the posterior cingulate gyrus demonstrated unique involvement in facilitation when short- and long-term memory converged. This pattern of results serves to further specify models of proactive interference-resolution.
Leakage radiation interference microscopy.
Descrovi, Emiliano; Barakat, Elsie; Angelini, Angelo; Munzert, Peter; De Leo, Natascia; Boarino, Luca; Giorgis, Fabrizio; Herzig, Hans Peter
2013-09-01
We present a proof of principle for a new imaging technique combining leakage radiation microscopy with high-resolution interference microscopy. By using oil immersion optics it is demonstrated that amplitude and phase can be retrieved from optical fields, which are evanescent in air. This technique is illustratively applied for mapping a surface mode propagating onto a planar dielectric multilayer on a thin glass substrate. The surface mode propagation constant estimated after Fourier transformation of the measured complex field is well matched with an independent measurement based on back focal plane imaging.
Beamforming design with proactive interference cancelation in MISO interference channels
Li, Yang; Tian, Yafei; Yang, Chenyang
2015-12-01
In this paper, we design coordinated beamforming at base stations (BSs) to facilitate interference cancelation at users in interference networks, where each BS is equipped with multiple antennas and each user is with a single antenna. By assuming that each user can select the best decoding strategy to mitigate the interference, either canceling the interference after decoding when it is strong or treating it as noise when it is weak, we optimize the beamforming vectors that maximize the sum rate for the networks under different interference scenarios and find the solutions of beamforming with closed-form expressions. The inherent design principles are then analyzed, and the performance gain over passive interference cancelation is demonstrated through simulations in heterogeneous cellular networks.
Asymptomatic Bacteriuria and Bacterial Interference.
Nicolle, Lindsay E
2015-10-01
Asymptomatic bacteriuria is very common. In healthy women, asymptomatic bacteriuria increases with age, from women age 80 years, but is uncommon in men until after age 50 years. Individuals with underlying genitourinary abnormalities, including indwelling devices, may also have a high frequency of asymptomatic bacteriuria, irrespective of age or gender. The prevalence is very high in residents of long-term-care facilities, from 25% to 50% of women and 15% to 40% of men. Escherichia coli is the most frequent organism isolated, but a wide variety of other organisms may occur. Bacteriuria may be transient or persist for a prolonged period. Pregnant women with asymptomatic bacteriuria identified in early pregnancy and who are untreated have a risk of pyelonephritis later in pregnancy of 20% to 30%. Bacteremia is frequent in bacteriuric subjects following mucosal trauma with bleeding, with 5% to 10% of patients developing severe sepsis or septic shock. These two groups with clear evidence of negative outcomes should be screened for bacteriuria and appropriately treated. Asymptomatic bacteriuria in other populations is benign and screening and treatment are not indicated. Antimicrobial treatment has no benefits but is associated with negative outcomes including reinfection with antimicrobial resistant organisms and a short-term increased frequency of symptomatic infection post-treatment. The observation of increased symptomatic infection post-treatment, however, has led to active investigation of bacterial interference as a strategy to prevent symptomatic episodes in selected high risk patients.
Graphene quantum interference photodetector
Directory of Open Access Journals (Sweden)
Mahbub Alam
2015-03-01
Full Text Available In this work, a graphene quantum interference (QI photodetector was simulated in two regimes of operation. The structure consists of a graphene nanoribbon, Mach–Zehnder interferometer (MZI, which exhibits a strongly resonant transmission of electrons of specific energies. In the first regime of operation (that of a linear photodetector, low intensity light couples two resonant energy levels, resulting in scattering and differential transmission of current with an external quantum efficiency of up to 5.2%. In the second regime of operation, full current switching is caused by the phase decoherence of the current due to a strong photon flux in one or both of the interferometer arms in the same MZI structure. Graphene QI photodetectors have several distinct advantages: they are of very small size, they do not require p- and n-doped regions, and they exhibit a high external quantum efficiency.
Substation electromagnetic interference
International Nuclear Information System (INIS)
Felic, G.; Shihab, S.
1997-01-01
The electric and magnetic transients in high voltage substations were studied. The electric field measurements were carried out in a 66 kV switchyard of a 500/220/66 kV substation in Melbourne, Australia. The measured waveforms make up a database to be used for reference in the testing of substation control and protection equipment. The objective of this study was to characterize the radiated interference caused by the operation of disconnect switches and circuit breakers. Disconnect switch transients can be a serious hazard for substations because the slow moving contacts during opening and closing can result in arcing events of several seconds duration. Circuit breaker transients were considered to be less hazardous. Transient magnetic fields of at least several tens of A/m can occur during the energization of the capacitor bank. Substation electronic equipment should be tested and protected against the coupling of these transients in order to avoid breakdowns. 5 refs., 4 figs
Autonomy, Competence and Non-interference
Roberts, Joseph T.F.
2017-01-01
In light of the variety of uses of the term autonomy in recent bioethics literature, in this paper, I suggest that competence, not being as contested, is better placed to play the anti-paternalistic role currently assigned to autonomy. The demonstration of competence, I will argue, can provide individuals with robust spheres of non-interference in which they can pursue their lives in accordance with their own values. This protection from paternalism is achieved by granting individuals rights ...
Acoustic and semantic interference effects in words and pictures.
Dhawan, M; Pellegrino, J W
1977-05-01
Interference effects for pictures and words were investigated using a probe-recall task. Word stimuli showed acoustic interference effects for items at the end of the list and semantic interference effects for items at the beginning of the list, similar to results of Kintsch and Buschke (1969). Picture stimuli showed large semantic interference effects at all list positions with smaller acoustic interference effects. The results were related to latency data on picture-word processing and interpreted in terms of the differential order, probability, and/or speed of access to acoustic and semantic levels of processing. A levels of processing explanation of picture-word retention differences was related to dual coding theory. Both theoretical positions converge on an explanation of picture-word retention differences as a function of the relative capacity for semantic or associative processing.
Interference Effects on the Recall of Pictures, Printed Words, and Spoken Words.
Burton, John K.; Bruning, Roger H.
1982-01-01
Nouns were presented in triads as pictures, printed words, or spoken words and followed by various types of interference. Measures of short- and long-term memory were obtained. In short-term memory, pictorial superiority occurred with acoustic, and visual and acoustic, but not visual interference. Long-term memory showed superior recall for…
Developmental Change in Proactive Interference.
Kail, Robert
2002-01-01
Two studies examined age-related change in proactive interference from previously learned material. The meta-analysis of 26 studies indicated that proactive interference decreased with age. The cross-sectional study found that third through sixth graders' and college students' recall was accurate on Trial 1, but became less so over Trials 2…
Sleep can reduce proactive interference.
Abel, Magdalena; Bäuml, Karl-Heinz T
2014-01-01
Sleep has repeatedly been connected to processes of memory consolidation. While extensive research indeed documents beneficial effects of sleep on memory, little is yet known about the role of sleep for interference effects in episodic memory. Although two prior studies reported sleep to reduce retroactive interference, no sleep effect has previously been found for proactive interference. Here we applied a study format differing from that employed by the prior studies to induce a high degree of proactive interference, and asked participants to encode a single list or two interfering lists of paired associates via pure study cycles. Testing occurred after 12 hours of diurnal wakefulness or nocturnal sleep. Consistent with the prior work, we found sleep in comparison to wake did not affect memory for the single list, but reduced retroactive interference. In addition we found sleep reduced proactive interference, and reduced retroactive and proactive interference to the same extent. The finding is consistent with the view that arising benefits of sleep are caused by the reactivation of memory contents during sleep, which has been suggested to strengthen and stabilise memories. Such stabilisation may make memories less susceptible to competition from interfering memories at test and thus reduce interference effects.
Output Interference in Recognition Memory
Criss, Amy H.; Malmberg, Kenneth J.; Shiffrin, Richard M.
2011-01-01
Dennis and Humphreys (2001) proposed that interference in recognition memory arises solely from the prior contexts of the test word: Interference does not arise from memory traces of other words (from events prior to the study list or on the study list, and regardless of similarity to the test item). We evaluate this model using output…
Interference Phenomenon with Mobile Displays
Trantham, Kenneth
2015-01-01
A simple experiment is presented in which the spacing and geometric pattern of pixels in mobile displays is measured. The technique is based on optical constructive interference. While the experiment is another opportunity to demonstrate wave interference from a grating-like structure, this can also be used to demonstrate concepts of solid state…
Interference effects in MSSM Higgs searches at the LHC
Energy Technology Data Exchange (ETDEWEB)
Fuchs, Elina [Weizmann Institute of Science, Rehovot (Israel); Weiglein, Georg [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2017-05-15
Complex parameters in the MSSM lead to mixing and interference between the two heavier neutral CP-even and CP-odd Higgs states. These effects can become very large in the case of almost degenerate states. In a CP-violating benchmark scenario, we investigate phenomenological implications of such interferences in view of the LHC searches for heavy Higgs bosons decaying to a pair of τ-leptons and produced in gluon fusion and in association with b-quarks. Strongly destructive effects leave parameter regions unconstrained that would be regarded as excluded if no interference terms were taken into account.
Radio Frequency Interference Mitigation
An, T.; Chen, X.; Mohan, P.; Lao, B. Q.
2017-09-01
The observational facilities of radio astronomy keep constant upgrades and developments to achieve better capabilities including increasing the time of the data recording and frequency resolutions, and increasing the receiving and recording bandwidth. However in contrast, only a limited spectrum resource has been allocated to radio astronomy by the International Telecommunication Union, resulting in that the radio observational instrumentations are inevitably exposed to undesirable radio frequency interference (RFI) signals which originate mainly from the terrestrial human activity and are becoming stronger with time. RFIs degrade the quality of data and even lead to invalid data. The impact of RFIs on scientific outcome becomes more and more serious. In this article, the requirement for RFI mitigation is motivated, and the RFI characteristics, mitigation techniques, and strategies are reviewed. The mitigation strategies adopted at some representative observatories, telescopes, and arrays are also introduced. The advantages and shortcomings of the four classes of RFI mitigation strategies are discussed and presented, applicable at the connected causal stages: preventive, pre-detection, pre-correlation, and post-correlation. The proper identification and flagging of RFI is the key to the reduction of data loss and improvement in data quality, and is also the ultimate goal of developing RFI mitigation technique. This can be achieved through a strategy involving a combination of the discussed techniques in stages. The recent advances in the high speed digital signal processing and high performance computing allow for performing RFI excision of the large data volumes generated from large telescopes or arrays in both real time and offline modes, aiding the proposed strategy.
Quantum interference effects for the electronic fluctuations in quantum dots
Energy Technology Data Exchange (ETDEWEB)
Ramos, J.G.G.S. [Universidade Federal da Paraiba (UFPB), Rio Tinto, PB (Brazil). Departamento de Ciencias Exatas; Hussein, M.S. [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Fisica; Barbosa, A.L.R. [Universidade Federal Rural de Pernambuco (UAEADTec/UFRPE), Recife, PE (Brazil). Unidade Academica de Ensino a Distancia. Pos-Graduacao em Fisica Aplicada
2014-07-01
For the main quantum interference term of coherent electronic transport, we study the effect of temperature, perpendicular and/or parallel magnetic fields, spin-orbit coupling and tunneling rates in both metallic grains and mesoscopic heterostructures. We show that the Zeeman effects determines a crucial way to characterize the quantum interference phenomena of the noise for anisotropic systems (mesoscopic heterostructures), qualitatively distinct from those observed in isotropic structures (metallic grains). (author)
Quantum interference effects for the electronic fluctuations in quantum dots
International Nuclear Information System (INIS)
Ramos, J.G.G.S.; Hussein, M.S.; Barbosa, A.L.R.
2014-01-01
For the main quantum interference term of coherent electronic transport, we study the effect of temperature, perpendicular and/or parallel magnetic fields, spin-orbit coupling and tunneling rates in both metallic grains and mesoscopic heterostructures. We show that the Zeeman effects determines a crucial way to characterize the quantum interference phenomena of the noise for anisotropic systems (mesoscopic heterostructures), qualitatively distinct from those observed in isotropic structures (metallic grains). (author)
Quantum interference vs. quantum chaos in the nuclear shell model
International Nuclear Information System (INIS)
Fernández, Gerardo; Hautefeuille, M; Velázquez, V; Hernández, Edna M; Landa, E; Morales, I O; Frank, A; Fossion, R; Vargas, C E
2015-01-01
In this paper we study the complexity of the nuclear states in terms of a two body quadupole-quadrupole interaction. Energy distributions and eigenvectors composition exhibit a visible interference pattern which is dependent on the intensity of the interaction. In analogy with optics, the visibility of the interference is related to the purity of the states, therefore, we show that the fluctuations associated with quantum chaos have as their origin the remaining quantum coherence with a visibility magnitude close to 5%
Quantum Interference of Molecules
Indian Academy of Sciences (India)
IAS Admin
in terms of the established laws of classical physics and called for a radically different way of thinking. This led to the ... (Compton, 1922), the exclusion principle (Pauli, 1922), ... tian Huygens had proposed the wave theory of light in. 1690 ...
Interference management using direct sequence spread spectrum ...
African Journals Online (AJOL)
Interference management using direct sequence spread spectrum (DSSS) technique ... Journal of Fundamental and Applied Sciences ... Keywords: DSSS, LTE network; Wi-Fi network; SINR; interference management and interference power.
Optical interference with noncoherent states
International Nuclear Information System (INIS)
Sagi, Yoav; Firstenberg, Ofer; Fisher, Amnon; Ron, Amiram
2003-01-01
We examine a typical two-source optical interference apparatus consisting of two cavities, a beam splitter, and two detectors. We show that field-field interference occurs even when the cavities are not initially in coherent states but rather in other nonclassical states. However, we find that the visibility of the second-order interference, that is, the expectation values of the detectors' readings, changes from 100%, when the cavities are prepared in coherent states, to zero visibility when they are initially in single Fock states. We calculate the fourth-order interference, and for the latter case find that it corresponds to a case where the currents oscillate with 100% visibility, but with a random phase for every experiment. Finally, we suggest an experimental realization of the apparatus with nonclassical sources
Quantum Erasure: Quantum Interference Revisited
Walborn, Stephen P.; Cunha, Marcelo O. Terra; Pádua, Sebastião; Monken, Carlos H.
2005-01-01
Recent experiments in quantum optics have shed light on the foundations of quantum physics. Quantum erasers - modified quantum interference experiments - show that quantum entanglement is responsible for the complementarity principle.
Interference, reduced action, and trajectories
Floyd, Edward R.
2006-01-01
Instead of investigating the interference between two stationary, rectilinear wave functions in a trajectory representation by examining the two rectilinear wave functions individually, we examine a dichromatic wave function that is synthesized from the two interfering wave functions. The physics of interference is contained in the reduced action for the dichromatic wave function. As this reduced action is a generator of the motion for the dichromatic wave function, it determines the dichroma...
Visual working memory capacity and proactive interference.
Hartshorne, Joshua K
2008-07-23
Visual working memory capacity is extremely limited and appears to be relatively immune to practice effects or the use of explicit strategies. The recent discovery that visual working memory tasks, like verbal working memory tasks, are subject to proactive interference, coupled with the fact that typical visual working memory tasks are particularly conducive to proactive interference, suggests that visual working memory capacity may be systematically under-estimated. Working memory capacity was probed behaviorally in adult humans both in laboratory settings and via the Internet. Several experiments show that although the effect of proactive interference on visual working memory is significant and can last over several trials, it only changes the capacity estimate by about 15%. This study further confirms the sharp limitations on visual working memory capacity, both in absolute terms and relative to verbal working memory. It is suggested that future research take these limitations into account in understanding differences across a variety of tasks between human adults, prelinguistic infants and nonlinguistic animals.
Visual working memory capacity and proactive interference.
Directory of Open Access Journals (Sweden)
Joshua K Hartshorne
Full Text Available BACKGROUND: Visual working memory capacity is extremely limited and appears to be relatively immune to practice effects or the use of explicit strategies. The recent discovery that visual working memory tasks, like verbal working memory tasks, are subject to proactive interference, coupled with the fact that typical visual working memory tasks are particularly conducive to proactive interference, suggests that visual working memory capacity may be systematically under-estimated. METHODOLOGY/PRINCIPAL FINDINGS: Working memory capacity was probed behaviorally in adult humans both in laboratory settings and via the Internet. Several experiments show that although the effect of proactive interference on visual working memory is significant and can last over several trials, it only changes the capacity estimate by about 15%. CONCLUSIONS/SIGNIFICANCE: This study further confirms the sharp limitations on visual working memory capacity, both in absolute terms and relative to verbal working memory. It is suggested that future research take these limitations into account in understanding differences across a variety of tasks between human adults, prelinguistic infants and nonlinguistic animals.
The Price of Fame: The Impact of Stimulus Familiarity on Proactive Interference Resolution
Prabhakaran, Ranjani; Thompson-Schill, Sharon L.
2011-01-01
Interference from previously learned information, known as proactive interference (PI), limits our memory retrieval abilities. Previous studies of PI resolution have focused on the role of short-term familiarity, or recency, in causing PI. In the present study, we investigated the impact of long-term stimulus familiarity on PI resolution…
Third order dielectric susceptibility in a model quantum paraelectric
International Nuclear Information System (INIS)
Martonak, R.; Tosatti, E.
1996-02-01
In the context of perovskite quantum paraelectrics, we study the effects of a quadrupolar interaction J q , in addition to the standard dipolar one J d . We concentrate here on the nonlinear dielectric response χ (3) P , as the main response function sensitive to quadrupolar (in our case antiquadrupolar) interactions. We employ a 3D quantum four-state lattice model and mean-field theory. The results show that inclusion of quadrupolar coupling of moderate strength (J q ∼ 1/4J d ) is clearly accompanied by a double change of sign of χ (3) P from negative to positive, near the quantum temperature T Q where the quantum paraelectric behaviour sets in. We fit our χ (3) to recent experimental data for SrTiO 3 , where the sign change is identified close to T Q ∼ 37 K. (author). 40 refs, 2 figs
Synthesis, characterization and third-order nonlinear optical ...
Indian Academy of Sciences (India)
On the other hand, our investigation reveals that the spectral dispersion characteristic of γ for silver nanoparticles-coated PDA nanovesicles is qualitatively similar to that observed for the uncoated PDA nanovesicles but bears no resemblance to that observed in silver nanoparticles. The presence of silver nanoparticles ...
Expanded porphyrins as third order non-linear optical materials ...
Indian Academy of Sciences (India)
WINTEC
function correlations ... An understanding of the structure–function corre- lations of these expanded porphyrins is an important first step for ... where χ (2) and χ (3) are the quadratic χ (2) (first- order) and χ (3) cubic (second-order) susceptibilities.
Computational studies of third-order nonlinear optical properties of ...
Indian Academy of Sciences (India)
Anuj Kumar
2017-06-20
Jun 20, 2017 ... Department of Physics, Jaypee University of Engineering and Technology, Raghogarh,. Guna 473 226, India. ∗ ... properties and other molecular properties of the organic nonlinear optical crystal 2-aminopyridinium p- toluenesulphonate ... nal processing, optical limiting, optical logic gates, laser radiation ...
Autonomous third-order duffing-holmes type chaotic oscillator
DEFF Research Database (Denmark)
Lindberg, Erik; Tamaseviciute, E; Mykolaitis, G
2009-01-01
feedback loop. In contrast to many other autonomous chaotic oscillators, including linear unstable resonators and nonlinear damping loops, the novel circuit is based on nonlinear resonator and linear damping loop in the negative feedback. SPICE simulation and hardware experimental investigations...
Evaluation of polymer based third order nonlinear integrated optics devices
Driessen, A.; Hoekstra, Hugo; Blom, F.C.; Horst, F.; Horst, F.; Krijnen, Gijsbertus J.M.; van Schoot, J.B.P.; van Schoot, J.B.P.; Lambeck, Paul; Popma, T.J.A.; Diemeer, Mart
Nonlinear polymers are promising materials for high speed active integrated optics devices. In this paper we evaluate the perspectives polymer based nonlinear optical devices can offer. Special attention is directed to the materials aspects. In our experimental work we applied mainly Akzo Nobel DANS
Oscillation of third-order functional differential equations
Directory of Open Access Journals (Sweden)
Blanka Baculikova
2010-08-01
Applying suitable comparison theorems we present new criteria for oscillation or certain asymptotic behavior of nonoscillatory solutions of (\\ref{E0}. Obtained results essentially improve and complement earlier ones. Various examples are considered to illustrate the main results.
Pressure tunable cascaded third order nonlinearity and temporal pulse switching
DEFF Research Database (Denmark)
Eilenberger, Falk; Bache, Morten; Minardi, Stefano
2013-01-01
Effects based on the χ(3)-nonlinearity are arguably the most commonly discussed nonlinear interactions in photonics. In the description of pulse propagation, however, the generation of the third harmonic (TH) is commonly neglected, because it is strongly phase mismatched in most materials...
Ablation and optical third-order nonlinearities in Ag nanoparticles
Directory of Open Access Journals (Sweden)
Carlos Torres-Torres
2010-11-01
Full Text Available Carlos Torres-Torres1, Néstor Peréa-López2, Jorge Alejandro Reyes-Esqueda3, Luis Rodríguez-Fernández3, Alejandro Crespo-Sosa3, Juan Carlos Cheang-Wong3, Alicia Oliver31Section of Graduate Studies and Research, School of Mechanical and Electrical Engineering, National Polytechnic Institute, Zacatenco, Distrito Federal, Mexico; 2Laboratory for Nanoscience and Nanotechnology Research and Advanced Materials Department, IPICYT, Camino a la Presa San Jose, San Luis Potosi, Mexico; 3Instituto de Física, Universidad Nacional Autónoma de México, A.P. 20-364, México, D.F. 01000, MéxicoAbstract: The optical damage associated with high intensity laser excitation of silver nanoparticles (NPs was studied. In order to investigate the mechanisms of optical nonlinearity of a nanocomposite and their relation with its ablation threshold, a high-purity silica sample implanted with Ag ions was exposed to different nanosecond and picosecond laser irradiations. The magnitude and sign of picosecond refractive and absorptive nonlinearities were measured near and far from the surface plasmon resonance (SPR of the Ag NPs with a self-diffraction technique. Saturable optical absorption and electronic polarization related to self-focusing were identified. Linear absorption is the main process involved in nanosecond laser ablation, but nonlinearities are important for ultrashort picosecond pulses when the absorptive process become significantly dependent on the irradiance. We estimated that near the resonance, picosecond intraband transitions allow an expanded distribution of energy among the NPs, in comparison to the energy distribution resulting in a case of far from resonance, when the most important absorption takes place in silica. We measured important differences in the ablation threshold and we estimated that the high selectiveness of the SPR of Ag NPs as well as their corresponding optical nonlinearities can be strongly significant for laser-induced controlled explosions, with potential applications for biomedical photothermal processes.Keywords: nonlinear optics, laser irradiation, metallic nanoparticles, Kerr effect, nonlinear optical absorption
General existence results for nonconvex third order differential inclusions
Directory of Open Access Journals (Sweden)
Messaoud Bounkhel
2010-04-01
where $F:[0,T]\\times \\mathbb{H}\\times \\mathbb{H} \\times \\mathbb{H}\\rightarrow \\mathbb{H}$ is a continuous set-valued mapping, $G:\\mathbb{H}\\times \\mathbb{H} \\times \\mathbb{H}\\rightarrow \\mathbb{H}$ is an upper semi-continuous set-valued mapping with $G(x,y,z\\subset \\partial^C g(z$ where $g: \\mathbb{H}\\rightarrow \\mathbb{R}$ is a uniformly regular function over $S$ and locally Lipschitz and $S$ is a ball compact subset of a separable Hilbert space $\\mathbb{H}$.
Interference in motor learning - is motor interference sensory?
DEFF Research Database (Denmark)
Jensen, Jesper Lundbye; Petersen, Tue Hvass; Rothwell, John C
mechanisms determine whether or not interference occurs. We hypothesised that interference requires the same neural circuits to be engaged in the two tasks and provoke competing processes of synaptic plasticity. To test this, subjects learned a ballistic ankle plantarflexion task. Early motor memory...... was disrupted by subsequent learning of a precision tracking task with the same agonist muscle group, but not by learning involving antagonist muscles or by voluntary agonist contractions that did not require learning. If the competing task was learned with the same agonist muscle group 4 hours following...
WEED INTERFERENCE IN EGGPLANT CROPS
Directory of Open Access Journals (Sweden)
LUIZ JUNIOR PEREIRA MARQUES
2017-01-01
Full Text Available Uncontrolled weed growth interferes with the growth eggplants and crop yields. To control weeds, the main weed species must be identified in crop growing areas and during weed control periods, as weed species might vary in relation to management practices. Therefore, this study aimed to identify the main weed species and determine the periods of weed interference in the eggplant cultivar Nápoli when grown under certain cultural practices, including plant staking and sprout thinning. The experiment was carried out in 2014 using a randomized complete block design, with 3 replications. The treatments consisted of 11 periods of (1 increasing weed control and (2 increasing coexistence of eggplant with weeds from the first day of transplanting (0-14, 0-28, 0-42, 0-56, 0-70, 0-84, 0-98, 0-112, 0-126, 0-140, and up do day 154. Eggplant staking and sprout thinning were performed 42 days after transplanting (DAT. Weed identification and crop yield assessments were performed to determine the Period Before Interference (PBI, Total Period of Interference Prevention (TPIP, and the Critical Period of Interference Prevention (CPIP. The major weeds found in the eggplant cultivar Nápoli were Eleusine indica, Portulaca oleracea, and Cyperus rotundus. Coexistence between the weed community and the eggplant throughout the entire crop production cycle reduced eggplant fruit yield by 78%. The PBI was 29 DAT and the TPIP was 48 DAT, resulting in 19 days of CPIP.
Interference in ballistic motor learning - is motor interference really sensory?
DEFF Research Database (Denmark)
Lundbye-Jensen, Jesper; Petersen, Tue Hvass; Rothwell, John C
Skill gained after a short period of practice in one motor task can be abolished if a second task is learned shortly afterwards. We hypothesised that interference requires the same circuits to be engaged in the two tasks and provoke competing processes of synaptic plasticity. To test this, subjects...
'Quantum interference with slits' revisited
Rothman, Tony; Boughn, Stephen
2011-01-01
Marcella has presented a straightforward technique employing the Dirac formalism to calculate single- and double-slit interference patterns. He claims that no reference is made to classical optics or scattering theory and that his method therefore provides a purely quantum mechanical description of these experiments. He also presents his calculation as if no approximations are employed. We show that he implicitly makes the same approximations found in classical treatments of interference and that no new physics has been introduced. At the same time, some of the quantum mechanical arguments Marcella gives are, at best, misleading.
Parton showers with quantum interference
Nagy, Zoltan
2007-01-01
We specify recursive equations that could be used to generate a lowest order parton shower for hard scattering in hadron-hadron collisions. The formalism is based on the factorization soft and collinear interactions from relatively harder interactions in QCD amplitudes. It incorporates quantum interference between different amplitudes in those cases in which the interference diagrams have leading soft or collinear singularities. It incorporates the color and spin information carried by partons emerging from a hard interaction. One motivation for this work is to have a method that can naturally cooperate with next-to-leading order calculations.
Parton showers with quantum interference
International Nuclear Information System (INIS)
Nagy, Zoltan; Soper, Davison E.
2007-01-01
We specify recursive equations that could be used to generate a lowest order parton shower for hard scattering in hadron-hadron collisions. The formalism is based on the factorization soft and collinear interactions from relatively harder interactions in QCD amplitudes. It incorporates quantum interference between different amplitudes in those cases in which the interference diagrams have leading soft or collinear singularities. It incorporates the color and spin information carried by partons emerging from a hard interaction. One motivation for this work is to have a method that can naturally cooperate with next-to-leading order calculations
Dynamic visual noise interferes with storage in visual working memory.
Dean, Graham M; Dewhurst, Stephen A; Whittaker, Annalise
2008-01-01
Several studies have demonstrated that dynamic visual noise (DVN) does not interfere with memory for random matrices. This has led to suggestions that (a) visual working memory is distinct from imagery, and (b) visual working memory is not a gateway between sensory input and long-term storage. A comparison of the interference effects of DVN with memory for matrices and colored textures shows that DVN can interfere with visual working memory, probably at a level of visual detail not easily supported by long-term memory structures or the recoding of the visual pattern elements. The results support a gateway model of visuospatial working memory and raise questions about the most appropriate ways to measure and model the different levels of representation of information that can be held in visual working memory.
Escaping the recent past: which stimulus dimensions influence proactive interference?
Craig, Kimberly S; Berman, Marc G; Jonides, John; Lustig, Cindy
2013-07-01
Proactive interference occurs when information from the past disrupts current processing and is a major source of confusion and errors in short-term memory (STM; Wickens, Born, & Allen, Journal of Verbal Learning and Verbal Behavior, 2:440-445, 1963). The present investigation examines potential boundary conditions for interference, testing the hypothesis that potential competitors must be similar along task-relevant dimensions to influence proactive interference effects. We manipulated both the type of task being completed (Experiments 1, 2, and 3) and dimensions of similarity irrelevant to the current task (Experiments 4 and 5) to determine how the recent presentation of a probe item would affect the speed with which participants could reject that item. Experiments 1, 2, and 3 contrasted STM judgments, which require temporal information, with semantic and perceptual judgments, for which temporal information is irrelevant. In Experiments 4 and 5, task-irrelevant information (perceptual similarity) was manipulated within the recent probes task. We found that interference from past items affected STM task performance but did not affect performance in semantic or perceptual judgment tasks. Conversely, similarity along a nominally irrelevant perceptual dimension did not affect the magnitude of interference in STM tasks. Results are consistent with the view that items in STM are represented by noisy codes consisting of multiple dimensions and that interference occurs when items are similar to each other and, thus, compete along the dimensions relevant to target selection.
Conducted interference on smart meters
Keyer, Cornelis H.A.; Leferink, Frank
2017-01-01
The increasing conducted interference caused by modern electronic equipment is causing more problems for electronic, or static, energy meters. These meters are called smart meters when equipped with a communication link, and are replacing the conventional electromechanical meters. It is known that
Electromagnetic Interference in Smart Grids
Leferink, Frank; Keyer, Cees
2017-01-01
The increasing conducted interference caused by modern electronic equipment is causing more problems for electronic, or static, energy meters. If equipped with a communication link they are called smart meter. Because the smart meter is a key device in smart grids, any deviation has huge impact on
"Quantum Interference with Slits" Revisited
Rothman, Tony; Boughn, Stephen
2011-01-01
Marcella has presented a straightforward technique employing the Dirac formalism to calculate single- and double-slit interference patterns. He claims that no reference is made to classical optics or scattering theory and that his method therefore provides a purely quantum mechanical description of these experiments. He also presents his…
Interference and memory capacity limitations.
Endress, Ansgar D; Szabó, Szilárd
2017-10-01
Working memory (WM) is thought to have a fixed and limited capacity. However, the origins of these capacity limitations are debated, and generally attributed to active, attentional processes. Here, we show that the existence of interference among items in memory mathematically guarantees fixed and limited capacity limits under very general conditions, irrespective of any processing assumptions. Assuming that interference (a) increases with the number of interfering items and (b) brings memory performance to chance levels for large numbers of interfering items, capacity limits are a simple function of the relative influence of memorization and interference. In contrast, we show that time-based memory limitations do not lead to fixed memory capacity limitations that are independent of the timing properties of an experiment. We show that interference can mimic both slot-like and continuous resource-like memory limitations, suggesting that these types of memory performance might not be as different as commonly believed. We speculate that slot-like WM limitations might arise from crowding-like phenomena in memory when participants have to retrieve items. Further, based on earlier research on parallel attention and enumeration, we suggest that crowding-like phenomena might be a common reason for the 3 major cognitive capacity limitations. As suggested by Miller (1956) and Cowan (2001), these capacity limitations might arise because of a common reason, even though they likely rely on distinct processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
REM sleep rescues learning from interference
McDevitt, Elizabeth A.; Duggan, Katherine A.; Mednick, Sara C.
2015-01-01
Classical human memory studies investigating the acquisition of temporally-linked events have found that the memories for two events will interfere with each other and cause forgetting (i.e., interference; Wixted, 2004). Importantly, sleep helps consolidate memories and protect them from subsequent interference (Ellenbogen, Hulbert, Stickgold, Dinges, & Thompson-Schill, 2006). We asked whether sleep can also repair memories that have already been damaged by interference. Using a perceptual learning paradigm, we induced interference either before or after a consolidation period. We varied brain states during consolidation by comparing active wake, quiet wake, and naps with either non-rapid eye movement sleep (NREM), or both NREM and REM sleep. When interference occurred after consolidation, sleep and wake both produced learning. However, interference prior to consolidation impaired memory, with retroactive interference showing more disruption than proactive interference. Sleep rescued learning damaged by interference. Critically, only naps that contained REM sleep were able to rescue learning that was highly disrupted by retroactive interference. Furthermore, the magnitude of rescued learning was correlated with the amount of REM sleep. We demonstrate the first evidence of a process by which the brain can rescue and consolidate memories damaged by interference, and that this process requires REM sleep. We explain these results within a theoretical model that considers how interference during encoding interacts with consolidation processes to predict which memories are retained or lost. PMID:25498222
Interference Lithography for Vertical Photovoltaics
Balls, Amy; Pei, Lei; Kvavle, Joshua; Sieler, Andrew; Schultz, Stephen; Linford, Matthew; Vanfleet, Richard; Davis, Robert
2009-10-01
We are exploring low cost approaches for fabricating three dimensional nanoscale structures. These vertical structures could significantly improve the efficiency of devices made from low cost photovoltaic materials. The nanoscale vertical structure provides a way to increase optical absorption in thin photovoltaic films without increasing the electronic carrier separation distance. The target structure is a high temperature transparent template with a dense array of holes on a 400 - 600 nm pitch fabricated by a combination of interference lithography and nanoembossing. First a master was fabricated using ultraviolet light interference lithography and the pattern was transferred into a silicon wafer master by silicon reactive ion etching. Embossing studies were performed with the master on several high temperature polymers.
The effects of trait impulsivity on proactive and reactive interference control.
Xiang, Ling; Chen, Yan; Chen, Antao; Zhang, Fenghua; Xu, Fuming; Wang, Baoxi
2018-02-01
The current study used event-related brain potentials (ERPs) to explore whether self-reported trait impulsivity in healthy individuals might be differentially related to proactive and reactive interference control. Participants with high and low impulsivity (HI and LI, respectively) performed a modified version of the prime-target interference task. Proactive interference control was induced in the mostly incongruent (MI) context and reactive interference control was induced in the mostly congruent (MC) context. Although the behavioral data revealed no difference between HI and LI individuals in terms of the interference effects (incongruent - congruent) under both contexts, the ERP results showed that impulsivity has a different influence on the interference effects under different task contexts. In the MC context, the interference effects on the medial frontal negativity (MFN) and the negative sustained potential (N-SP) were greater, while that on the positive sustained potential (P-SP) were smaller in the HI compared to those in the LI group. This suggests that high levels of impulsivity might be associated with a reduced efficiency of the processes supporting reactive control to resolve interference when interference is not expected. In contrast, the three ERP indices (MFN, P-SP, and N-SP) of interference processing in the MI context were insensitive to variations in impulsivity. This suggests that HI individuals might be as effective as LI individuals in recruiting proactive control for sustained active maintenance of task goals to anticipate and prevent interference throughout the experimental blocks where interference occurs frequently. In conclusion, these results indicate that impulsivity has a more negative influence on reactive interference control than on proactive interference control. Copyright © 2017. Published by Elsevier B.V.
Interference and memory capacity effects in memristive systems
Hermiz, John; Chang, Ting; Du, Chao; Lu, Wei
2013-02-01
Short-term memory implies the existence of a capacity limit beyond which memory cannot be securely formed and retained. The underlying mechanisms are believed to be two primary factors: decay and interference. Here, we demonstrate through both simulation and experiment that the memory capacity effect can be implemented in a parallel memristor circuit, where decay and interference are achieved by the inherent ion diffusion in the device and the competition for current supply in the circuit, respectively. This study suggests it is possible to emulate high-level biological behaviors with memristor circuits and will stimulate continued studies on memristor-based neuromorphic circuits.
Interference effects in new physics processes at the LHC
International Nuclear Information System (INIS)
Fuchs, Elina
2015-09-01
Interference effects between nearly mass-degenerate particles are addressed in this thesis, comprising higher-order calculations, a modelindependent method to calculate interference terms efficiently and a phenomenological application to current Higgs searches at the LHC. Predictions of cross sections and decay widths can be severely affected by interference terms between quasi-degenerate states arising in models beyond the Standard Model. We formulate a generalisation of the narrow-width approximation (NWA) which allows for a consistent treatment of such effects by factorising the interference term into on-shell matrix elements of the production and decay parts, optionally further approximated as simple interference weight factors, incorporating oneloop and real corrections in a UV- and IR-finite way. We apply the generalised NWA to interfering MSSM Higgs bosons in the process χ 0 4 →χ 0 1 Φ→χ 0 1 τ + τ - , Φ=h, H and achieve an agreement of better than 1% with the unfactorised three-body decay of the neutralino χ 0 4 at NLO. Further, we derive the approximation of the full propagator matrix of the three neutral MSSM Higgs bosons in terms of Breit- Wigner propagators and on-shell wave-function normalisation factors Z. This is found to accurately reproduce the full mixing properties also in the case of complex MSSM parameters. Moreover, it enables the implementation of the total width at the highest available order. Using the Breit-Wigner and Z-factor formalism, we calculate CP-violating interference effects of the neutral MSSM Higgs bosons in the process b anti b→h 1,2,3 →τ +τ - , induced by the phase φ A t . We find a very significant, destructive interference between h 2 and h 3 , particularly for large μ. As a consequence, a considerable parameter region in the complex M mod+ h scenario, which would appear to be ruled out if this interference were neglected, actually escapes the current exclusion bounds from the LHC.
Image hiding using optical interference
Zhang, Yan; Wang, Weining
2010-09-01
Optical image encryption technology has attracted a lot of attentions due to its large capacitance and fast speed. In conventional image encryption methods, the random phase masks are used as encryption keys to encode the images into white noise distribution. Therefore, this kind of methods requires interference technology to record complex amplitude and is vulnerable to attack techniques. The image hiding methods which employ the phase retrieve algorithm to encode the images into two or more phase masks are proposed, the hiding process is carried out within a computer using iterative algorithm. But the iterative algorithms are time consumed. All method mentioned above are based on the optical diffraction of the phase masks. In this presentation, a new optical image hiding method based on optical interference is proposed. The coherence lights which pass through two phase masks are combined by a beam splitter. Two beams interfere with each other and the desired image appears at the pre-designed plane. Two phase distribution masks are design analytically; therefore, the hiding speed can be obviously improved. Simulation results are carried out to demonstrate the novelty of the new proposed methods. This method can be expanded for double images hiding.
Quantum interference in plasmonic circuits.
Heeres, Reinier W; Kouwenhoven, Leo P; Zwiller, Valery
2013-10-01
Surface plasmon polaritons (plasmons) are a combination of light and a collective oscillation of the free electron plasma at metal/dielectric interfaces. This interaction allows subwavelength confinement of light beyond the diffraction limit inherent to dielectric structures. As a result, the intensity of the electromagnetic field is enhanced, with the possibility to increase the strength of the optical interactions between waveguides, light sources and detectors. Plasmons maintain non-classical photon statistics and preserve entanglement upon transmission through thin, patterned metallic films or weakly confining waveguides. For quantum applications, it is essential that plasmons behave as indistinguishable quantum particles. Here we report on a quantum interference experiment in a nanoscale plasmonic circuit consisting of an on-chip plasmon beamsplitter with integrated superconducting single-photon detectors to allow efficient single plasmon detection. We demonstrate a quantum-mechanical interaction between pairs of indistinguishable surface plasmons by observing Hong-Ou-Mandel (HOM) interference, a hallmark non-classical interference effect that is the basis of linear optics-based quantum computation. Our work shows that it is feasible to shrink quantum optical experiments to the nanoscale and offers a promising route towards subwavelength quantum optical networks.
Performance of barcode scanner using peak detection with interference from LED lamps
Deng, X.; Zijlstra, P.; Zhang, J.; Wu, Y.; Zhou, G.; Linnartz, J.-P.
2015-01-01
This paper presents a new model for barcode scanners that suffer from the interference of LED lamps, to quantify the system performance in terms of Timing Signal-to-Interference Ratio (TSIR), particularly as a function of modulation depth and frequency of the flicker in the LED lighting. Physical
Carbon nanostructure composite for electromagnetic interference
Indian Academy of Sciences (India)
2015-05-30
based composite materials for electromagnetic interference (EMI) shielding. With more and more electronic gadgets being used at different frequencies, there is a need for shielding them from one another to avoid interference.
Can Two-Photon Interference be Considered the Interference of Two Photons?
International Nuclear Information System (INIS)
Pittman, T.B.; Strekalov, D.V.; Migdall, A.; Rubin, M.H.; Sergienko, A.V.; Shih, Y.H.
1996-01-01
We report on a open-quote open-quote postponed compensation close-quote close-quote experiment in which the observed two-photon entangled state interference cannot be pictured in terms of the overlap of the two individual photon wave packets of a parametric down-conversion pair on a beam splitter. In the sense of a quantum eraser, the distinguishability of the different two-photon Feynman amplitudes leading to a coincidence detection is removed by delaying the compensation until after the output of an unbalanced two-photon interferometer. copyright 1996 The American Physical Society
In-Band Interference Effects on UTRA LTE Uplink Resource Block Allocation
DEFF Research Database (Denmark)
Priyanto, Basuki Endah; Sørensen, Troels Bundgaard; Jensen, Ole Kiel
2008-01-01
In this paper we investigate the impact of in-band interference on the uplink multiple access of UMTS Terrestrial Radio Access, long term evolution (UTRA LTE). In- band and out-of-band interference arise as a result of transmitter imperfections. Out-of- band, or adjacent channel, interference can......, and when the interfering signal is received at higher power spectral density (PSD). The effect of frequency offset and different PSD level from the UE interferers to a victim UE is studied. The impact on different UE resource block size allocation is also investigated. The results are obtained from an LTE...
On the interference rejection capabilities of triangular antenna array for cellular base stations
Atat, Rachad; Shakir, Muhammad; Alouini, Mohamed-Slim
2012-01-01
In this paper, we present the performance analysis of the triangular antenna arrays in terms of the interference rejection capability. In this context, we derive an expression to calculate the spatial interference suppression coefficient for the triangular antenna array with variable number of antenna elements. The performance of the triangular antenna array has been compared with the circular antenna array with respect to interference suppression performance, steering beam pattern, beamwidth and directivity. Simulation results show that the triangular array with large number of elements produces a sharper beamwidth and better interference suppression performance than the circular antenna array. © 2012 IEEE.
On the interference rejection capabilities of triangular antenna array for cellular base stations
Atat, Rachad
2012-03-01
In this paper, we present the performance analysis of the triangular antenna arrays in terms of the interference rejection capability. In this context, we derive an expression to calculate the spatial interference suppression coefficient for the triangular antenna array with variable number of antenna elements. The performance of the triangular antenna array has been compared with the circular antenna array with respect to interference suppression performance, steering beam pattern, beamwidth and directivity. Simulation results show that the triangular array with large number of elements produces a sharper beamwidth and better interference suppression performance than the circular antenna array. © 2012 IEEE.
Cooperation for Interference Management: A GDoF Perspective
Gherekhloo, Soheil
2016-10-13
The impact of cooperation on interference management is investigated by studying an elemental wireless network, the so-called symmetric interference relay channel (IRC), from a generalized degrees of freedom (GDoF) perspective. This is motivated by the fact that the deployment of relays is considered as a remedy to overcome the bottleneck of current systems in terms of achievable rates. The focus of this paper is on the regime in which the interference link is weaker than the source-relay link in the IRC. Our approach toward studying the GDoF goes through the capacity analysis of the linear deterministic IRC (LD-IRC). New upper bounds on the sum capacity of the LD-IRC based on genie-aided approaches are established. These upper bounds together with some existing upper bounds are achieved by using four novel transmission schemes. Extending the upper bounds and the transmission schemes to the Gaussian case, the GDoF of the Gaussian IRC is characterized for the aforementioned regime. This completes the GDoF results available in the literature for the symmetric GDoF. It turns out that even if the incoming and outgoing links of the relay are both weaker than the desired channel, involving a relay can increase the GDoF. Interestingly, utilizing the relay in this case can increase the slope of the GDoF from -2 [in the interference channel (IC)] to -1 or 0. This shrinks the regime where ignoring the interference by treating it as noise is optimal. Furthermore, the analysis shows that if the relay ingoing and outgoing links are sufficiently strong, the relay is able to neutralize the interference completely. In this case, the bottleneck of the transmission will be the interference links, and hence, the GDoF increases if the interference link gets stronger. It is shown that in the strong interference regime, in contrast to the IC, the GDoF can be a monotonically decreasing function of the interference level. © 1963-2012 IEEE.
Coordinate Representations for Interference Reduction in Motor Learning.
Directory of Open Access Journals (Sweden)
Sang-Hoon Yeo
Full Text Available When opposing force fields are presented alternately or randomly across trials for identical reaching movements, subjects learn neither force field, a behavior termed 'interference'. Studies have shown that a small difference in the endpoint posture of the limb reduces this interference. However, any difference in the limb's endpoint location typically changes the hand position, joint angles and the hand orientation making it ambiguous as to which of these changes underlies the ability to learn dynamics that normally interfere. Here we examine the extent to which each of these three possible coordinate systems--Cartesian hand position, shoulder and elbow joint angles, or hand orientation--underlies the reduction in interference. Subjects performed goal-directed reaching movements in five different limb configurations designed so that different pairs of these configurations involved a change in only one coordinate system. By specifically assigning clockwise and counter-clockwise force fields to the configurations we could create three different conditions in which the direction of the force field could only be uniquely distinguished in one of the three coordinate systems. We examined the ability to learn the two fields based on each of the coordinate systems. The largest reduction of interference was observed when the field direction was linked to the hand orientation with smaller reductions in the other two conditions. This result demonstrates that the strongest reduction in interference occurred with changes in the hand orientation, suggesting that hand orientation may have a privileged role in reducing motor interference for changes in the endpoint posture of the limb.
Quantum eraser for three-slit interference
Indian Academy of Sciences (India)
Naveed Ahmad Shah
2017-11-09
Nov 9, 2017 ... Abstract. It is well known that in a two-slit interference experiment, if the information, on which of the two paths the particle followed, is stored in a quantum path detector, the interference is destroyed. However, in a set-up where this path information is 'erased', the interference can reappear. Such a set-up is ...
An accumulator model of semantic interference
van Maanen, Leendert; van Rijn, Hedderik
To explain latency effects in picture-word interference tasks, cognitive models need to account for both interference and stimulus onset asynchrony (SOA) effects. As opposed to most models of picture-word interference, which model the time course during the task in a ballistic manner, the RACE model
47 CFR 27.1221 - Interference protection.
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false Interference protection. 27.1221 Section 27... Technical Standards § 27.1221 Interference protection. (a) Interference protection will be afforded to BRS... height benchmark (hbm). (c) Protection for Receiving Antennas not Exceeding the Height Benchmark. Absent...
A generalized and parameterized interference model for cognitive radio networks
Mahmood, Nurul Huda
2011-06-01
For meaningful co-existence of cognitive radios with primary system, it is imperative that the cognitive radio system is aware of how much interference it generates at the primary receivers. This can be done through statistical modeling of the interference as perceived at the primary receivers. In this work, we propose a generalized model for the interference generated by a cognitive radio network, in the presence of small and large scale fading, at a primary receiver located at the origin. We then demonstrate how this model can be used to estimate the impact of cognitive radio transmission on the primary receiver in terms of different outage probabilities. Finally, our analytical findings are validated through some selected computer-based simulations. © 2011 IEEE.
Quantum Interference and Coherence Theory and Experiments
Ficek, Zbigniew; Rhodes, William T; Asakura, Toshimitsu; Brenner, Karl-Heinz; Hänsch, Theodor W; Kamiya, Takeshi; Krausz, Ferenc; Monemar, Bo; Venghaus, Herbert; Weber, Horst; Weinfurter, Harald
2005-01-01
For the first time, this book assembles in a single volume accounts of many phenomena involving quantum interference in optical fields and atomic systems. It provides detailed theoretical treatments and experimental analyses of such phenomena as quantum erasure, quantum lithography, multi-atom entanglement, quantum beats, control of decoherence, phase control of quantum interference, coherent population trapping, electromagnetically induced transparency and absorption, lasing without inversion, subluminal and superluminal light propagation, storage of photons, quantum interference in phase space, interference and diffraction of cold atoms, and interference between Bose-Einstein condensates. This book fills a gap in the literature and will be useful to both experimentalists and theoreticians.
INTERFERENCE OF UNIDIRECTIONAL SHOCK WAVES
Directory of Open Access Journals (Sweden)
P. V. Bulat
2015-05-01
Full Text Available Subject of study.We consider interference of unidirectional shock waves or, as they are called, catching up shock waves. The scope of work is to give a classification of the shock-wave structures that arise in this type of interaction of shock waves, and the area of their existence. Intersection of unidirectional shock waves results in arising of a shock-wave structure at the intersection point, which contains the main shock wave, tangential discontinuity and one more reflected gas-dynamic discontinuity of unknown beforehand type. The problem of determining the type of reflected discontinuity is the main problem that one has to solve in the study of catching shock waves interference. Main results.The paper presents the pictures of shock-wave structures arising at the interaction of catching up shock waves. The areas with a regular and irregular unidirectional interaction of shocks are described. Characteristic shock-wave structures are of greatest interest, where reflected gas-dynamic discontinuity degenerates into discontinuous characteristics. Such structures have a number of extreme properties. We have found the areas of existence for such shock-wave structures. There are also areas in which the steady-state solution is not available. The latter has determined revival of interest for the theoretical study of the problem, because the facts of sudden shock-wave structure destruction inside the air intake of supersonic aircrafts at high Mach numbers have been discovered. Practical significance.The theory of interference for unidirectional shock waves and design procedure are usable in the design of supersonic air intakes. It is also relevant for application possibility investigation of catching up oblique shock waves to create overcompressed detonation in perspective detonation air-jet and rocket engines.
Ren, Zhi-Gang; Sun, Sha; Dai, Min; Wang, Hui-Fang; Lü, Chun-Ning; Lang, Jian-Ping; Sun, Zhen-Rong
2011-09-07
Reactions of the preformed cluster [(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)(MeCN)(2)](ClO(4))(2) (1) with two tetraphosphine ligands, 1,4-N,N,N',N'-tetra(diphenylphosphanylmethyl)benzene diamine (dpppda) and N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylene diamine (dppeda), produced two bicyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)](2)(L)}(ClO(4))(4) (3: L = dpppda; 4: L = dppeda). Analogous reactions of 1 or [(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)(MeCN)(2)](PF(6))(2) (2) with two N,P mixed ligands, N,N-bi(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy) and N-diphenylphosphanylmethyl-4-aminopyridine (dppmapy), afforded two monocyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)](2)(L)(2)}X(4) (5: L = bdppmapy, X = ClO(4); 6: L = dppmapy, X = PF(6)). Compounds 3-6 were fully characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H and (31)P{(1)H} NMR spectra, ESI-MS and single-crystal X-ray crystallography. In the tetracations of 3-6, two cubane-like [Mo(2)(μ(3)-S)(4)Cu(2)] cores are linked either by one dpppda or dppeda bridge to form a bicyclic structure or by a pair of bdppmapy or dppmapy bridges to afford a monocyclic structure. The third-order nonlinear optical (NLO) properties of 1 and 3-6 in MeCN were also investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 50 fs pulse width at 800 nm. Compounds 3-6 exhibited enhanced third-order NLO performances relative to that of 1. This journal is © The Royal Society of Chemistry 2011
Embracing interference in wireless systems
Gollakota, Shyamnath
2014-01-01
The wireless medium is a shared resource. If nearby devices transmit at thesame time, their signals interfere, resulting in a collision. In traditionalnetworks, collisions cause the loss of the transmitted information. For thisreason, wireless networks have been designed with the assumption thatinterference is intrinsically harmful and must be avoided.This book, a revised version of the author's award-winning Ph.D.dissertation, takes an alternate approach: Instead of viewing interferenceas an inherently counterproductive phenomenon that should to be avoided, wedesign practical systems that tra
Interference Mitigation in Cognitive Femtocells
DEFF Research Database (Denmark)
Da Costa, Gustavo Wagner Oliveira; Cattoni, Andrea Fabio; Alvarez Roig, Victor
2010-01-01
, management and optimization can be prohibitive. Instead, self-optimization of an uncoordinated deployment should be considered. Cognitive Radio enabled femtocells are considered to be a promising solution to enable self-optimizing femtocells to effectively manage the inter-cell interference, especially...... in densely deployed femto scenarios. In this paper, two key elements of cognitive femtocells are combined: a power control algorithm and a fully distributed dynamic spectrum allocation method. The resulting solution was evaluated through system-level simulations and compared to the separate algorithms...
THE ANALYSIS OF INTERFERENCE ON WRITING ASSIGNMENTS OF THE MIDWIFERY STUDENTS
Directory of Open Access Journals (Sweden)
I G. A. Agung Sintha Satwika
2013-11-01
Full Text Available This research aims at investigating and analyzing the interference which occurred in English text made by the students of Akademi Kebidanan Bali Wisnu Dharma. The data of this writing were collected from the writing assignment of the students at Akademi Kebidanan Bali Wisnu Dharma, which was divided into six groups. The data were obtained by reading intensively those texts and followed by applying the note taking technique. The result of this study indicates that the interference occurred on those writing assignments in terms of semantics level, spelling, copula, syntax, literal translation, redundancy, over generalization, and interference in terms of English pronoun.
Diffractive interference optical analyzer (DiOPTER)
Sasikumar, Harish; Prasad, Vishnu; Pal, Parama; Varma, Manoj M.
2016-03-01
This report demonstrates a method for high-resolution refractometric measurements using, what we have termed as, a Diffractive Interference Optical Analyzer (DiOpter). The setup consists of a laser, polarizer, a transparent diffraction grating and Si-photodetectors. The sensor is based on the differential response of diffracted orders to bulk refractive index changes. In these setups, the differential read-out of the diffracted orders suppresses signal drifts and enables time-resolved determination of refractive index changes in the sample cell. A remarkable feature of this device is that under appropriate conditions, the measurement sensitivity of the sensor can be enhanced by more than two orders of magnitude due to interference between multiply reflected diffracted orders. A noise-equivalent limit of detection (LoD) of 6x10-7 RIU was achieved in glass. This work focuses on devices with integrated sample well, made on low-cost PDMS. As the detection methodology is experimentally straightforward, it can be used across a wide array of applications, ranging from detecting changes in surface adsorbates via binding reactions to estimating refractive index (and hence concentration) variations in bulk samples. An exciting prospect of this technique is the potential integration of this device to smartphones using a simple interface based on transmission mode configuration. In a transmission configuration, we were able to achieve an LoD of 4x10-4 RIU which is sufficient to explore several applications in food quality testing and related fields. We are envisioning the future of this platform as a personal handheld optical analyzer for applications ranging from environmental sensing to healthcare and quality testing of food products.
Directory of Open Access Journals (Sweden)
Krishnan Sridhar
2007-01-01
Full Text Available This paper introduces a novel algorithm to excise single and multicomponent chirp-like interferences in direct sequence spread spectrum (DSSS communications. The excision algorithm consists of two stages: adaptive signal decomposition stage and directional element detection stage based on the Hough-Radon transform (HRT. Initially, the received spread spectrum signal is decomposed into its time-frequency (TF functions using an adaptive signal decomposition algorithm, and the resulting TF functions are mapped onto the TF plane. We then use a line detection algorithm based on the HRT that operates on the image of the TF plane and detects energy varying directional elements that satisfy a parametric constraint. Interference is modeled by reconstructing the corresponding TF functions detected by the HRT, and subtracted from the received signal. The proposed technique has two main advantages: (i it localizes the interferences on the TF plane with no cross-terms, thus facilitating simple filtering techniques based on thresholding of the TF functions, and is an efficient way to excise the interference; (ii it can be used for the detection of any directional interferences that can be parameterized. Simulation results with synthetic models have shown successful performance with linear and quadratic chirp interferences for single and multicomponent interference cases. The proposed method excises the interference even under very low SNR conditions of dB, and the technique could be easily extended to any interferences that could be represented by a parametric equation in the TF plane.
Coping with Radio Frequency Interference
Lewis, B. M.
2009-01-01
The radio spectrum is a finite resource, on which humanity makes many demands. And pressure on it is ever increasing with the development of new technology and ideas for radio services. After all, we all benefit from wifi and cell phones. Radio astronomers have a small percentage of the spectrum allocated to them at octave intervals in the metre-centimetre bands, and at important frequencies, such as that of the 21cm line of HI. Signals from other services, as well as from our own poorly-engineered equipment, sometimes contaminate our bands: these signals constitute RFI. These may totally obliterate the astronomical signal, or, in the case of CLOUDSAT, may be capable of completely destroying a receiver, which introduces us to the new possibility of 'destructive interference'. A geo-stationary satellite can block access to a piece of sky from one site. Good equipment design eliminates self-inflicted interference, while physical separation often provides adequate practical mitigation at many frequencies. However, new observatories end up being located in the West Australian desert or Antarctica. In future they may be on the back side of the Moon. But there is no Earth-bound protection via physical separation against satellite signals. Some mitigation can be achieved by frequent data dumps and the excision of RFI, or by real-time detection and blanking of the receiver, or by more sophisticated algoriths. Astronomers of necessity aim to achieve mitigation via coordination, at the local level, and by participating in spectrum management at the national and international levels. This involves them spending a lot of time in Geneva at the International Telegraphic Union protecting their access to spectrum, and access to clean spectrum from the L3 point and the far side of the Moon.
Filtering algorithm for dotted interferences
Energy Technology Data Exchange (ETDEWEB)
Osterloh, K., E-mail: kurt.osterloh@bam.de [Federal Institute for Materials Research and Testing (BAM), Division VIII.3, Radiological Methods, Unter den Eichen 87, 12205 Berlin (Germany); Buecherl, T.; Lierse von Gostomski, Ch. [Technische Universitaet Muenchen, Lehrstuhl fuer Radiochemie, Walther-Meissner-Str. 3, 85748 Garching (Germany); Zscherpel, U.; Ewert, U. [Federal Institute for Materials Research and Testing (BAM), Division VIII.3, Radiological Methods, Unter den Eichen 87, 12205 Berlin (Germany); Bock, S. [Technische Universitaet Muenchen, Lehrstuhl fuer Radiochemie, Walther-Meissner-Str. 3, 85748 Garching (Germany)
2011-09-21
An algorithm has been developed to remove reliably dotted interferences impairing the perceptibility of objects within a radiographic image. This particularly is a major challenge encountered with neutron radiographs collected at the NECTAR facility, Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II): the resulting images are dominated by features resembling a snow flurry. These artefacts are caused by scattered neutrons, gamma radiation, cosmic radiation, etc. all hitting the detector CCD directly in spite of a sophisticated shielding. This makes such images rather useless for further direct evaluations. One approach to resolve this problem of these random effects would be to collect a vast number of single images, to combine them appropriately and to process them with common image filtering procedures. However, it has been shown that, e.g. median filtering, depending on the kernel size in the plane and/or the number of single shots to be combined, is either insufficient or tends to blur sharp lined structures. This inevitably makes a visually controlled processing image by image unavoidable. Particularly in tomographic studies, it would be by far too tedious to treat each single projection by this way. Alternatively, it would be not only more comfortable but also in many cases the only reasonable approach to filter a stack of images in a batch procedure to get rid of the disturbing interferences. The algorithm presented here meets all these requirements. It reliably frees the images from the snowy pattern described above without the loss of fine structures and without a general blurring of the image. It consists of an iterative, within a batch procedure parameter free filtering algorithm aiming to eliminate the often complex interfering artefacts while leaving the original information untouched as far as possible.
Filtering algorithm for dotted interferences
International Nuclear Information System (INIS)
Osterloh, K.; Buecherl, T.; Lierse von Gostomski, Ch.; Zscherpel, U.; Ewert, U.; Bock, S.
2011-01-01
An algorithm has been developed to remove reliably dotted interferences impairing the perceptibility of objects within a radiographic image. This particularly is a major challenge encountered with neutron radiographs collected at the NECTAR facility, Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II): the resulting images are dominated by features resembling a snow flurry. These artefacts are caused by scattered neutrons, gamma radiation, cosmic radiation, etc. all hitting the detector CCD directly in spite of a sophisticated shielding. This makes such images rather useless for further direct evaluations. One approach to resolve this problem of these random effects would be to collect a vast number of single images, to combine them appropriately and to process them with common image filtering procedures. However, it has been shown that, e.g. median filtering, depending on the kernel size in the plane and/or the number of single shots to be combined, is either insufficient or tends to blur sharp lined structures. This inevitably makes a visually controlled processing image by image unavoidable. Particularly in tomographic studies, it would be by far too tedious to treat each single projection by this way. Alternatively, it would be not only more comfortable but also in many cases the only reasonable approach to filter a stack of images in a batch procedure to get rid of the disturbing interferences. The algorithm presented here meets all these requirements. It reliably frees the images from the snowy pattern described above without the loss of fine structures and without a general blurring of the image. It consists of an iterative, within a batch procedure parameter free filtering algorithm aiming to eliminate the often complex interfering artefacts while leaving the original information untouched as far as possible.
Proactive Interference in Human Predictive Learning
Castro, Leyre; Ortega, Nuria; Matute, Helena
2002-01-01
The impairment in responding to a secondly trained association because of the prior training of another (i.e., proactive interference) is a well-established effect in human and animal research, and it has been demonstrated in many paradigms. However, learning theories have been concerned with proactive interference only when the competing stimuli have been presented in compound at some moment of the training phase. In this experiment we investigated the possibility of proactive interference b...
Laser reflector with an interference coating
International Nuclear Information System (INIS)
Vol'pyan, O D; Semenov, A A; Yakovlev, P P
1998-01-01
An analysis was made of the reflectivity of interference coatings intended for the use in optical pumping of solid-state lasers. Ruby and Nd 3+ :YAG lasers were used as models in comparative pumping efficiency measurements, carried out employing reflectors with interference and silver coatings. Estimates of the service life of reflectors with interference coatings were obtained. The power of a thermo-optical lens was reduced by the use of such coatings in cw lasers. (laser system components)
Using Interference to Block RFID Tags
DEFF Research Database (Denmark)
Krigslund, Rasmus; Popovski, Petar; Pedersen, Gert Frølund
We propose a novel method to block RFID tags from responding, using intentional interference. We focus on the experimental evaluation, where we impose interference on the download and uplink, respectively. The results are positive, where modulated CCI shows most effective to block a tag.......We propose a novel method to block RFID tags from responding, using intentional interference. We focus on the experimental evaluation, where we impose interference on the download and uplink, respectively. The results are positive, where modulated CCI shows most effective to block a tag....
Electromagnetic Interference (EMI) and TEMPEST Test Facility
Federal Laboratory Consortium — Electromagnetic Interference (EMI), Electromagnetic Compatibility (EMC) and TEMPEST testing are conducted at EPG's Blacktail Canyon Test Facility in one of its two...
Chlorinated Cyanurates: Method Interferences and Application Implications
Experiments were conducted to investigate method interferences, residual stability, regulated DBP formation, and a water chemistry model associated with the use of Dichlor & Trichlor in drinking water.
Chemical Principles and Interference in the Electrical Conductance of Single Molecules
DEFF Research Database (Denmark)
Borges, Anders Christian
, the conductance of molecules can vary orders of magnitude and the concept of interference is believed to play a major role in this. This thesis investigates the links between single molecule conductance, chemistry and interference effects in short organic molecules. It is investigated to which extent...... the conductance can be understood in terms of separate contributions and when the effects of interference are important. Links between chemical principles and constructive- and destructive interference effects are demonstrated using a combination of simple models, atomistic calculations and Scanning......-Tunneling Microscope Break-Junction experiments (STM-BJ). It is demonstrated that these links can be used to design molecules exhibiting surprising interference effects and to interpret and predict the trends in the characteristic conductance of single molecules without resorting to numerical computational methods...
INTERFERENCE OF COUNTERPROPAGATING SHOCK WAVES
Directory of Open Access Journals (Sweden)
P. V. Bulat
2015-03-01
-dynamic discontinuities, the intensities corresponding to the transition from regular to irregular interference were described. Numerical calculations of the shock-wave structure transformation in the conditions of hysteresis were performed. The results were compared with the experiments carried out by hydraulic analogy method. Practical significance. Results of the work complement well the theory of stationary gas-dynamic discontinuities interference and can be used at designing of perspective images of supersonic and hypersonic aircraft.
景山, 望; 箱田, 裕司; Kageyama, Nozomu; Hakoda, Yuji
2011-01-01
Stroop interference and reverse-Stroop interference are one of the easiest and most powerful effects to demonstrate in a classroom. Therefore, they have been studied not only through basic research in the laboratory but also through applied research in extreme environments. First, we reviewed studies tha investigated Stroop interference and reverse-Stroop interference as hallmark measures of selective at attention and conflict resolution. Second, we reviewed studies that examined the effects ...
Directory of Open Access Journals (Sweden)
Gregory C Burgess
2010-09-01
Full Text Available A critical aspect of executive control is the ability to limit the adverse effects of interference. Previous studies have shown activation of left ventrolateral prefrontal cortex after the onset of interference, suggesting that interference may be resolved in a reactive manner. However, we suggest that interference control may also operate in a proactive manner to prevent effects of interference. The current study investigated the temporal dynamics of interference control by varying two factors - interference expectancy and fluid intelligence (gF - that could influence whether interference control operates proactively versus reactively.A modified version of the recent negatives task was utilized. Interference expectancy was manipulated across task blocks by changing the proportion of recent negative (interference trials versus recent positive (facilitation trials. Furthermore, we explored whether gF affected the tendency to utilize specific interference control mechanisms. When interference expectancy was low, activity in lateral prefrontal cortex replicated prior results showing a reactive control pattern (i.e., interference-sensitivity during probe period. In contrast, when interference expectancy was high, bilateral prefrontal cortex activation was more indicative of proactive control mechanisms (interference-related effects prior to the probe period. Additional results suggested that the proactive control pattern was more evident in high gF individuals, whereas the reactive control pattern was more evident in low gF individuals.The results suggest the presence of two neural mechanisms of interference control, with the differential expression of these mechanisms modulated by both experimental (e.g., expectancy effects and individual difference (e.g., gF factors.
An interference account of the missing-VP effect
Directory of Open Access Journals (Sweden)
Markus eBader
2015-06-01
Full Text Available Sentences with doubly center-embedded relative clauses in which a verb phrase (VP is missing are sometimes perceived as grammatical, thus giving rise to an illusion of grammaticality. In this paper, we provide a new account of why missing-VP sentences, which are both complex and ungrammatical, lead to an illusion of grammaticality, the so-called missing-VP effect. We propose that the missing-VP effect in particular, and processing difficulties with multiply center-embedded clauses more generally, are best understood as resulting from interference during cue-based retrieval. When processing a sentence with double center-embedding, a retrieval error due to interference can cause the verb of an embedded clause to be erroneously attached into a higher clause. This can lead to an illusion of grammaticality in the case of missing-VP sentences and to processing complexity in the case of complete sentences with double center-embedding. Evidence for an interference account of the missing-VP effect comes from experiments that have investigated the missing-VP effect in German using a speeded grammaticality judgments procedure. We review this evidence and then present two new experiments that show that the missing VP effect can be found in German also with less restricting procedures. One experiment was a questionnaire study which required grammaticality judgments from participants but without imposing any time constraints. The second experiment used a self-paced reading procedure and did not require any judgments. Both experiments confirm the prior findings of missing-VP effects in German and also show that the missing-VP effect is subject to a primacy effect as known from the memory literature. Based on this evidence, we argue that an account of missing-VP effects in terms of interference during cue-based retrieval is superior to accounts in terms of limited memory resources or in terms of experience with embedded structures.
The Nature and Diagnosis of Interference Phenomena.
Denison, Norman
1966-01-01
The recognition of the systematic nature of the interference of the mother tongue when learning a second language is among the most significant advances in linguistics for the teaching and learning of foreign languages. The work of Weinreich showed that interference between language systems--the absorption of loan words, calques, and phonological,…
Interferences in place attachment: implications for wilderness
Erin K. Sharpe; Alan W. Ewert
2000-01-01
Previous research on place attachment has tended to focus on attachment formation, with relatively little attention given to factors that disrupt or interfere with formed place attachments. Interferences to attachments are a worthy research area for two reasons: 1) The factors of place attachment are often more salient when being disrupted, and 2) place attachment...
Interference and the Law of Energy Conservation
Drosd, Robert; Minkin, Leonid; Shapovalov, Alexander S.
2014-01-01
Introductory physics textbooks consider interference to be a process of redistribution of energy from the wave sources in the surrounding space resulting in constructive and destructive interferences. As one can expect, the total energy flux is conserved. However, one case of apparent non-conservation energy attracts great attention. Imagine that…
47 CFR 24.237 - Interference protection.
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false Interference protection. 24.237 Section 24.237... SERVICES Broadband PCS § 24.237 Interference protection. (a) All licensees are required to coordinate their... protection criterion shall be such that the interfering signal will not produce more than 1.0 dB degradation...
Optimal interference code based on machine learning
Qian, Ye; Chen, Qian; Hu, Xiaobo; Cao, Ercong; Qian, Weixian; Gu, Guohua
2016-10-01
In this paper, we analyze the characteristics of pseudo-random code, by the case of m sequence. Depending on the description of coding theory, we introduce the jamming methods. We simulate the interference effect or probability model by the means of MATLAB to consolidate. In accordance with the length of decoding time the adversary spends, we find out the optimal formula and optimal coefficients based on machine learning, then we get the new optimal interference code. First, when it comes to the phase of recognition, this study judges the effect of interference by the way of simulating the length of time over the decoding period of laser seeker. Then, we use laser active deception jamming simulate interference process in the tracking phase in the next block. In this study we choose the method of laser active deception jamming. In order to improve the performance of the interference, this paper simulates the model by MATLAB software. We find out the least number of pulse intervals which must be received, then we can make the conclusion that the precise interval number of the laser pointer for m sequence encoding. In order to find the shortest space, we make the choice of the greatest common divisor method. Then, combining with the coding regularity that has been found before, we restore pulse interval of pseudo-random code, which has been already received. Finally, we can control the time period of laser interference, get the optimal interference code, and also increase the probability of interference as well.
Electron quantum interferences and universal conductance fluctuations
International Nuclear Information System (INIS)
Benoit, A.; Pichard, J.L.
1988-05-01
Quantum interferences yield corrections to the classical ohmic behaviour predicted by Boltzmann theory in electronic transport: for instance the well-known ''weak localization'' effects. Furthermore, very recently, quantum interference effects have been proved to be responsible for statistically different phenomena, associated with Universal Conductance Fluctuations and observed on very small devices [fr
Complete destructive interference of partially coherent fields
Gbur, G.J.; Visser, T.D.; Wolf, E.
2004-01-01
A three-point source model is used to study the interference of wavefields which are mutually partially coherent. It is shown that complete destructive interference of the fields is possible in such a "three-pinhole interferometer" even if the sources are not fully coherent with respect to each
STRUCTURE FORMATION PRINCIPLES OF INTERFERENCE BEAM SPLITTERS
Directory of Open Access Journals (Sweden)
L. A. Gubanova
2012-01-01
Full Text Available The methodology of interference beam splitters construction, formed by symmetric cells of dielectric layers is considered. The methodology of short-wave and long-wave interference beam splitters formation is given. The impact analysis of symmetric cells number and their structure on output parameters is considered.
Belief attribution despite verbal interference.
Forgeot d'Arc, Baudouin; Ramus, Franck
2011-05-01
False-belief (FB) tasks have been widely used to study the ability of individuals to represent the content of their conspecifics' mental states (theory of mind). However, the cognitive processes involved are still poorly understood, and it remains particularly debated whether language and inner speech are necessary for the attribution of beliefs to other agents. We present a completely nonverbal paradigm consisting of silent animated cartoons in five closely related conditions, systematically teasing apart different aspects of scene analysis and allowing the assessment of the attribution of beliefs, goals, and physical causation. In order to test the role of language in belief attribution, we used verbal shadowing as a dual task to inhibit inner speech. Data on 58 healthy adults indicate that verbal interference decreases overall performance, but has no specific effect on belief attribution. Participants remained able to attribute beliefs despite heavy concurrent demands on their verbal abilities. Our results are most consistent with the hypothesis that belief attribution is independent from inner speech.
Laser self-mixing interference fibre sensor
International Nuclear Information System (INIS)
Zhu Jun; Zhao Yan; Jin Guofan
2008-01-01
Fibre sensors exhibit a number of advantages over other sensors such as high sensitivity, electric insulation, corrosion resistance, interference rejection and so on. And laser self-mixing interference can accurately detect the phase difference of feedback light. In this paper, a novel laser self-mixing interference fibre sensor that combines the advantages of fibre sensors with those of laser self-mixing interference is presented. Experimental configurations are set up to study the relationship between laser power output and phase of laser feedback light when the fibre trembles or when the fibre is stretched or pressed. The theoretical analysis of pressure sensors based on laser self-mixing interference is indicated to accord with the experimental results. (classical areas of phenomenology)
Collision-induced destructive quantum interference
International Nuclear Information System (INIS)
Yang Xihua; Sun Zhenrong; Zhang Shi'an; Ding Liang'en; Wang Zugeng
2005-01-01
We conduct theoretical studies on the collision-induced destructive quantum interference of two-colour two-photon transitions in an open rhomb-type five-level system with a widely separated doublet by the density matrix approach. The effects of the collision-induced decay rates, the ratio of the transition dipole moments and the energy separation of the doublet on the interference are analysed. It is shown that a narrow dip appears in the excitation spectrum due to the collision-induced destructive interference, and that the narrow interference dip still exists even when the collision broadening is comparable to the energy separation of the doublet. The physical origin of the collision-induced destructive quantum interference is analysed in the dressed-atom picture
Interference of identical particles from entanglement to boson-sampling
International Nuclear Information System (INIS)
Tichy, Malte C
2014-01-01
Progress in the reliable preparation, coherent propagation and efficient detection of many-body states has recently brought collective quantum phenomena of many identical particles into the spotlight. This tutorial introduces the physics of many-boson and many-fermion interference required for the description of current experiments and for the understanding of novel approaches to quantum computing. The field is motivated via the two-particle case, for which the uncorrelated, classical dynamics of distinguishable particles is compared to the quantum behaviour of identical bosons and fermions. Bunching of bosons is opposed to anti-bunching of fermions, while both species constitute equivalent sources of bipartite two-level entanglement. The realms of indistinguishable and distinguishable particles are connected by a monotonic transition, on a scale defined by the coherence length of the interfering particles. As we move to larger systems, any attempt to understand many particles via the two-particle paradigm fails: in contrast to two-particle bunching and anti-bunching, the very same signatures can be exhibited by bosons and fermions, and coherent effects dominate over statistical behaviour. The simulation of many-boson interference, termed boson-sampling, entails a qualitatively superior computational complexity when compared to fermions. The problem can be tamed by an artificially designed symmetric instance, which allows a systematic understanding of coherent bosonic and fermionic signatures for arbitrarily large particle numbers, and a means to stringently assess many-particle interference. The hierarchy between bosons and fermions also characterizes multipartite entanglement generation, for which bosons again clearly outmatch fermions. Finally, the quantum-to-classical transition between many indistinguishable and many distinguishable particles features non-monotonic structures, which dismisses the single-particle coherence length as unique indicator for
Chemical binding effects in resonance - potential interference scattering for harmonic crystals
International Nuclear Information System (INIS)
Kuwaifi, A.; Summerfield, G.C.
1991-01-01
The neutron scattering cross section which is the quantity directly measured in experiments is given by the absolute square of the scattering amplitude. For energies near a resonance, this yields three terms: potential, resonant and interference. In this paper we deal with the interference neutron scattering cross section which is written in terms of a three-point correlation function. This function is calculated for the ideal gas and harmonic crystal models. For short collision times, the interference result for harmonic crystals is the same as the ideal gas but it has an effective temperature. This is the same effective temperature as was previously found for absorption and pure resonant processes. Therefore, the interference scattering cross section can be treated in the same way as resonant scattering and absorption are treated using an ideal gas result with the usual effective temperature. (author)
Des interferences culturelles a surmonter (Overcoming Cultural Interference).
Mueller, Theodore
The English speaker learning French tends to interpret the sound characteristics of the second language according to English conventions. The term "sound characteristics" as used here refers to the phonetic aspects, the rhythm, and the intonation of French. A number of examples are given to support the theory that insufficient knowledge of these…
Modeling channel interference in an orbital angular momentum-multiplexed laser link
Anguita, Jaime A.; Neifeld, Mark A.; Vasic, Bane V.
2009-08-01
We study the effects of optical turbulence on the energy crosstalk among constituent orbital angular momentum (OAM) states in a vortex-based multi-channel laser communication link and determine channel interference in terms of turbulence strength and OAM state separation. We characterize the channel interference as a function of C2n and transmit OAM state, and propose probability models to predict the random fluctuations in the received signals for such architecture. Simulations indicate that turbulence-induced channel interference is mutually correlated across receive channels.
Christensen, L V; Rassouli, N M
1995-07-01
In 12 subjects, a rigid unilateral intercuspal interference (minimum mean height of 0.24 mm) was placed on either the right or left mandibular second premolar and first molar (sagittal physiological equilibrium point of the hemimandibular dental arch). During brisk and forceful clenching on the interference, bipolar surface electromyograms were obtained from the right and left masseter muscles. On the side opposite the interference, myoelectric clenching activity was significantly reduced. Correlation analyses showed that the interference elicited a non-linear (complex) co-ordination of the amplitude, but not the duration, of bilateral masseteric clenching activity, i.e. frequently there was significant motor facilitation on the side of the interference, and significant motor inhibition on the side opposite the interference. Theoretical considerations predicted that brief clenching on the interference would easily lead to frontal plane rotatory motions of the mandible which, indeed, occurred clinically.
The effect of an occlusal interference on the masticatory system. An experimental investigation.
Randow, K; Carlsson, K; Edlund, J; Oberg, T
1976-01-01
An experimental short term study on the effect of an occlusal interference on the path of closure of the mandible was carried out on 8 persons. The interference consisted of a gold inlay placed unilaterally in one of the mandibular first molars. Clinical and electromyographic studies revealed functional disturbances or pain in all subjects. The masticatory musculature was tender to palpation and showed coordinational disturbances; the TMJ showed tenderness to palpation, clicking and irregular movements and the interfering teeth periodontal tenderness.
Neurogenesis-mediated forgetting minimizes proactive interference.
Epp, Jonathan R; Silva Mera, Rudy; Köhler, Stefan; Josselyn, Sheena A; Frankland, Paul W
2016-02-26
Established memories may interfere with the encoding of new memories, particularly when existing and new memories overlap in content. By manipulating levels of hippocampal neurogenesis, here we show that neurogenesis regulates this form of proactive interference. Increasing hippocampal neurogenesis weakens existing memories and, in doing so, facilitates the encoding of new, conflicting (but not non-conflicting) information in mice. Conversely, decreasing neurogenesis stabilizes existing memories, and impedes the encoding of new, conflicting information. These results suggest that reduced proactive interference is an adaptive benefit of neurogenesis-induced forgetting.
Fingerprint extraction from interference destruction terahertz spectrum.
Xiong, Wei; Shen, Jingling
2010-10-11
In this paper, periodic peaks in a terahertz absorption spectrum are confirmed to be induced from interference effects. Theoretically, we explained the periodic peaks and calculated the locations of them. Accordingly, a technique was suggested, with which the interference peaks in a terahertz spectrum can be eliminated and therefore a real terahertz absorption spectrum can be obtained. Experimentally, a sample, Methamphetamine, was investigated and its terahertz fingerprint was successfully extracted from its interference destruction spectrum. This technique is useful in getting samples' terahertz fingerprint spectra, and furthermore provides a fast nondestructive testing method using a large size terahertz beam to identify materials.
Experimental occlusal interferences. Part III. Mandibular rotations induced by a rigid interference.
Rassouli, N M; Christensen, L V
1995-10-01
A rigid intercuspal interference (minimum mean height of 0.24 mm) was placed on either the right or left mandibular second premolar and first molar of 12 subjects. During brisk and forceful biting on the interference, rotational electrognathography measured maximum torque of the right and left mandibular condyles in the frontal and horizontal planes of orientation. All subjects showed frontal plan upward rotation (mean of 0.7 degrees) of the mandibular condyle contralateral to the interference. In 33% of the subjects there was no horizontal plane backward rotation. In 58% of the subjects there was horizontal plane backward rotation (mean of 0.5 degrees) of the mandibular condyle ipsilateral to the interference, and in one subject (8%) there was backward horizontal plane rotation (0.1 degree) of the mandibular condyle contralateral to the interference. It was inferred that the masseter muscle, ipsilateral to the interference, generated negative work in order to decelerate frontal plane 'unseating' of the mandibular condyle ipsilateral to the interference. It was inferred that the masseter muscle, contralateral to the interference, produced positive work in order to accelerate frontal plane 'seating' of the mandibular condyle contralateral to the interference. Finally, it was speculated that the impact forces of frontal plane 'seating' of the mandibular condyle, contralateral to the interference, might lead to 'vacuum sticking' of the temporomandibular joint disc because of the formation of negative hydrostatic pressures.
Interference Effects on the Recall of Pictures, Printed Words and Spoken Words.
Burton, John K.; Bruning, Roger H.
Thirty college undergraduates participated in a study of the effects of acoustic and visual interference on the recall of word and picture triads in both short-term and long-term memory. The subjects were presented 24 triads of monosyllabic nouns representing all of the possible combinations of presentation types: pictures, printed words, and…
Detection device for control rod interference
International Nuclear Information System (INIS)
Saito, Noboru.
1984-01-01
Purpose: To enable to detect the mechanical interference or friction between a control rod and a channel box automatically, simply and rapidly. Constitution: A signal from a gate circuit and a signal from a comparison mechanism are inputted into an AND circuit if a control rod has not been displaced by a predetermined distance within a prescribed time Δt after the output of an insertion or withdrawal signal for the control rod, by which a control-rod-interference signal is outputted from the AND circuit. Accordingly, the interference between the control rod and the channel box can be detected automatically, easily and rapidly. Furthermore, by properly adjusting the prescribed time Δt set by the gate circuit, the degree of the interference can also be detected, whereby the safety and the reliability of the reactor can be improved significantly. (Horiuchi, T.)
Relay self interference minimisation using tapped filter
Jazzar, Saleh; Al-Naffouri, Tareq Y.
2013-01-01
In this paper we introduce a self interference (SI) estimation and minimisation technique for amplify and forward relays. Relays are used to help forward signals between a transmitter and a receiver. This helps increase the signal coverage
Interference Coordination for Dense Wireless Networks
DEFF Research Database (Denmark)
Soret, Beatriz; Pedersen, Klaus I.; Jørgensen, Niels T.K.
2015-01-01
and dense deployment in Tokyo are compared. Evolution to DenseNets offers new opportunities for further development of downlink interference cooperation techniques. Various mechanisms in LTE and LTE-Advanced are revisited. Some techniques try to anticipate the future in a proactive way, whereas others......The promise of ubiquitous and super-fast connectivity for the upcoming years will be in large part fulfilled by the addition of base stations and spectral aggregation. The resulting very dense networks (DenseNets) will face a number of technical challenges. Among others, the interference emerges...... as an old acquaintance with new significance. As a matter of fact, the interference conditions and the role of aggressor and victim depend to a large extent on the density and the scenario. To illustrate this, downlink interference statistics for different 3GPP simulation scenarios and a more irregular...
Release From Proactive Interference with Young Children
Cann, Linda F.; And Others
1973-01-01
This demonstration of release from proactive interference with young children confirms the suggestion that the technique is appropriate for the study of developmental changes in the encoding of information. (Authors/CB)
Conducted Electromagnetic Interference (EMI) in Smart Grids
Smolenski, Robert
2012-01-01
As power systems develop to incorporate renewable energy sources, the delivery systems may be disrupted by the changes involved. The grid’s technology and management must be developed to form Smart Grids between consumers, suppliers and producers. Conducted Electromagnetic Interference (EMI) in Smart Grids considers the specific side effects related to electromagnetic interference (EMI) generated by the application of these Smart Grids. Conducted Electromagnetic Interference (EMI) in Smart Grids presents specific EMI conducted phenomena as well as effective methods to filter and handle them once identified. After introduction to Smart Grids, the following sections cover dedicated methods for EMI reduction and potential avenues for future development including chapters dedicated to: •potential system services, •descriptions of the EMI spectra shaping methods, •methods of interference voltage compensation, and theoretical analysis of experimental results. By focusing on these key aspects, Conducted El...
Resolving Business Process Interference via Dynamic Reconfiguration
van Beest, Nick R. T. P.; Bulanov, Pavel; Wortmann, Hans; Lazovik, Alexander; Maglio, PP; Weske, M; Yang, J; Fantinato, M
2010-01-01
For business processes supported by service-oriented information systems, concurrent execution of business processes still may yield undesired business outcomes as a result of process interference. For instance, concurrent processes may partially depend on a semantically identical process variable,
Fading and interference mitigation in wireless communications
Panic, Stefan; Anastasov, Jelena; Spalevic, Petar
2013-01-01
The rapid advancement of various wireless communication system services has created the need to analyze the possibility of their performance improvement. Introducing the basic principles of digital communications performance analysis and its mathematical formalization, Fading and Interference Mitigation in Wireless Communications will help you stay up to date with recent developments in the performance analysis of space diversity reception over fading channels in the presence of cochannel interference.The book presents a unified method for computing the performance of digital communication sys
Visual Working Memory Capacity and Proactive Interference
Hartshorne, Joshua
2008-01-01
BACKGROUND: Visual working memory capacity is extremely limited and appears to be relatively immune to practice effects or the use of explicit strategies. The recent discovery that visual working memory tasks, like verbal working memory tasks, are subject to proactive interference, coupled with the fact that typical visual working memory tasks are particularly conducive to proactive interference, suggests that visual working memory capacity may be systematically under-estimated. METHODOLOGY/P...
Cross-limb interference during motor learning.
Directory of Open Access Journals (Sweden)
Benedikt Lauber
Full Text Available It is well known that following skill learning, improvements in motor performance may transfer to the untrained contralateral limb. It is also well known that retention of a newly learned task A can be degraded when learning a competing task B that takes place directly after learning A. Here we investigate if this interference effect can also be observed in the limb contralateral to the trained one. Therefore, five different groups practiced a ballistic finger flexion task followed by an interfering visuomotor accuracy task with the same limb. Performance in the ballistic task was tested before the training, after the training and in an immediate retention test after the practice of the interference task for both the trained and the untrained hand. After training, subjects showed not only significant learning and interference effects for the trained limb but also for the contralateral untrained limb. Importantly, the interference effect in the untrained limb was dependent on the level of skill acquisition in the interfering motor task. These behavioural results of the untrained limb were accompanied by training specific changes in corticospinal excitability, which increased for the hemisphere ipsilateral to the trained hand following ballistic training and decreased during accuracy training of the ipsilateral hand. The results demonstrate that contralateral interference effects may occur, and that interference depends on the level of skill acquisition in the interfering motor task. This finding might be particularly relevant for rehabilitation.
Interference in the processing of adjunct control
Directory of Open Access Journals (Sweden)
Dan eParker
2015-09-01
Full Text Available Recent research on the memory operations used in language comprehension has revealed a selective profile of interference effects during memory retrieval. Dependencies such as subject-verb agreement show strong facilitatory interference effects from structurally inappropriate but feature-matching distractors, leading to illusions of grammaticality (Dillon, Mishler, Sloggett, & Phillips, 2013; Pearlmutter, Garnsey, & Bock, 1999; Wagers, Lau, & Phillips, 2009. In contrast, dependencies involving reflexive anaphors are generally immune to interference effects (Dillon et al., 2013; Sturt, 2003; Xiang, Dillon, & Phillips, 2009. This contrast has led to the proposal that all anaphors that are subject to structural constraints are immune to facilitatory interference. Here we use an animacy manipulation to examine whether adjunct control dependencies, which involve an interpreted anaphoric relation between a null subject and its licensor, are also immune to facilitatory interference effects. Our results show reliable facilitatory interference in the processing of adjunct control dependencies, which challenges the generalization that anaphoric dependencies as a class are immune to such effects. To account for the contrast between adjunct control and reflexive dependencies, we suggest that variability within anaphora could reflect either an inherent primacy of animacy cues in retrieval processes, or differential degrees of match between potential licensors and the retrieval probe.
Investigation of Interference Models for RFID Systems
Directory of Open Access Journals (Sweden)
Linchao Zhang
2016-02-01
Full Text Available The reader-to-reader collision in an RFID system is a challenging problem for communications technology. In order to model the interference between RFID readers, different interference models have been proposed, mainly based on two approaches: single and additive interference. The former only considers the interference from one reader within a certain range, whereas the latter takes into account the sum of all of the simultaneous interferences in order to emulate a more realistic behavior. Although the difference between the two approaches has been theoretically analyzed in previous research, their effects on the estimated performance of the reader-to-reader anti-collision protocols have not yet been investigated. In this paper, the influence of the interference model on the anti-collision protocols is studied by simulating a representative state-of-the-art protocol. The results presented in this paper highlight that the use of additive models, although more computationally intensive, is mandatory to improve the performance of anti-collision protocols.
Understanding quantum interference in general nonlocality
International Nuclear Information System (INIS)
Wang Haijun
2011-01-01
In this paper we attempt to give a new understanding of quantum double-slit interference of fermions in the framework of general nonlocality (GN) [J. Math. Phys. 49, 033513 (2008)] by studying the self-(inter)action of matter wave. From the metric of the GN, we derive a special formalism to interpret the interference contrast when the self-action is perturbative. According to the formalism, the characteristic of interference pattern is in agreement with experiment qualitatively. As examples, we apply the formalism to the cases governed by Schroedinger current and Dirac current, respectively, both of which are relevant to topology. The gap between these two cases corresponds to the fermion magnetic moment, which is possible to test in the near future. In addition, a general interference formalism for both perturbative and nonperturbative self-actions is presented. By analyzing the general formalism we predict that in the nonperturbative limit there is no interference at all. And by comparison with the special formalism of Schroedinger current, the coupling strength of self-action in the limit is found to be ∞. In the perturbative case, the interference from self-action turns out to be the same as that from the standard approach of quantum theory. Then comparing the corresponding coefficients quantitatively we conclude that the coupling strength of self-action in this case falls in the interval [0, 1].
Cho, Soohyun; Holyoak, Keith J; Cannon, Tyrone D
2007-09-01
We report a series of experiments using a pictorial analogy task designed to manipulate relational integration, interference resolution, and active maintenance simultaneously. The difficulty of the problems was varied in terms of the number of relations to be integrated, the need for interference resolution, and the duration of maintenance required to correctly solve the analogy. The participants showed decreases in performance when integrating multiple relations, as compared with a single relation, and when interference resolution was required in solving the analogy. When the participants were required to integrate multiple relations while simultaneously engaged in interference resolution, performance was worse, as compared with problems that incorporated either of these features alone. Maintenance of information across delays in the range of 1-4.5 sec led to greater decrements in visual memory, as compared with analogical reasoning. Misleading information caused interference when it had been necessarily attended to and maintained in working memory and, hence, had to be actively suppressed. However, sources of conflict within information that had not been attended to or encoded into working memory did not interfere with the ongoing controlled information processing required for relational integration. The findings provide evidence that relational integration and interference resolution depend on shared cognitive resources in working memory during analogical reasoning.
Takao, Hiroyuki; Yeh, Yu Chih; Arita, Hiroyuki; Obatake, Takumi; Sakano, Teppei; Kurihara, Minoru; Matsuki, Akira; Ishibashi, Toshihiro; Murayama, Yuichi
2016-10-01
Use of mobile phones has become a standard reality of everyday living for many people worldwide, including medical professionals, as data sharing has drastically helped to improve quality of care. This increase in the use of mobile phones within hospitals and medical facilities has raised concern regarding the influence of radio waves on medical equipment. Although comprehensive studies have examined the effects of electromagnetic interference from 2G wireless communication and personal digital cellular systems on medical equipment, similar studies on more recent wireless technologies such as Long Term Evolution, wideband code division multiple access, and high-speed uplink access have yet to be published. Numerous tests targeting current wireless technologies were conducted between December 2012 and March 2013 in an anechoic chamber, shielded from external radio signals, with a dipole antenna to assess the effects of smartphone interference on several types of medical equipment. The interference produced by electromagnetic waves across five frequency bands from four telecommunication standards was assessed on 49 components from 22 pieces of medical equipment. Of the 22 pieces of medical equipment tested, 13 experienced interference at maximum transmission power. In contrast, at minimum transmission power, the maximum interference distance varied from 2 to 5 cm for different wireless devices. Four machines were affected at the minimum transmission power, and the maximum interference distance at the maximum transmission power was 38 cm. Results show that the interference from smartphones on medical equipment is very controllable.
Motor learning interference is proportional to occlusion of LTP-like plasticity.
Cantarero, Gabriela; Tang, Byron; O'Malley, Rebecca; Salas, Rachel; Celnik, Pablo
2013-03-13
Learning interference occurs when learning something new causes forgetting of an older memory (retrograde interference) or when learning a new task disrupts learning of a second subsequent task (anterograde interference). This phenomenon, described in cognitive, sensory, and motor domains, limits our ability to learn multiple tasks in close succession. It has been suggested that the source of interference is competition of neural resources, although the neuronal mechanisms are unknown. Learning induces long-term potentiation (LTP), which can ultimately limit the ability to induce further LTP, a phenomenon known as occlusion. In humans we quantified the magnitude of occlusion of anodal transcranial direct current stimulation-induced increased excitability after learning a skill task as an index of the amount of LTP-like plasticity used. We found that retention of a newly acquired skill, as reflected by performance in the second day of practice, is proportional to the magnitude of occlusion. Moreover, the degree of behavioral interference was correlated with the magnitude of occlusion. Individuals with larger occlusion after learning the first skill were (1) more resilient to retrograde interference and (2) experienced larger anterograde interference when training a second task, as expressed by decreased performance of the learned skill in the second day of practice. This effect was not observed if sufficient time elapsed between training the two skills and LTP-like occlusion was not present. These findings suggest competition of LTP-like plasticity is a factor that limits the ability to remember multiple tasks trained in close succession.
Mishra, Jyoti; Zanto, Theodore; Nilakantan, Aneesha; Gazzaley, Adam
2013-08-01
Intrasensory interference during visual working memory (WM) maintenance by object stimuli (such as faces and scenes), has been shown to negatively impact WM performance, with greater detrimental impacts of interference observed in aging. Here we assessed age-related impacts by intrasensory WM interference from lower-level stimulus features such as visual and auditory motion stimuli. We consistently found that interference in the form of ignored distractions and secondary task interruptions presented during a WM maintenance period, degraded memory accuracy in both the visual and auditory domain. However, in contrast to prior studies assessing WM for visual object stimuli, feature-based interference effects were not observed to be significantly greater in older adults. Analyses of neural oscillations in the alpha frequency band further revealed preserved mechanisms of interference processing in terms of post-stimulus alpha suppression, which was observed maximally for secondary task interruptions in visual and auditory modalities in both younger and older adults. These results suggest that age-related sensitivity of WM to interference may be limited to complex object stimuli, at least at low WM loads. Copyright © 2013 Elsevier Ltd. All rights reserved.
Interference between nanoparticles and metal homeostasis
International Nuclear Information System (INIS)
Petit, A N; Catty, P; Charbonnier, P; Cuillel, M; Mintz, E; Moulis, J M; Niviere, V; Choudens, S Ollagnier de; Garcia, C Aude; Candeias, S; Chevallet, M; Collin-Faure, V; Lelong, C; Luche, S; Rabilloud, T; Casanova, A; Herlin-Boime, N; Douki, T; Ravanat, J L; Sauvaigo, S
2011-01-01
The TiO 2 nanoparticles (NPs) are now produced abundantly and widely used in a variety of consumer products. Due to the important increase in the production of TiO 2 -NPs, potential widespread exposure of humans and environment may occur during both the manufacturing process and final use. Therefore, the potential toxicity of TiO 2 -NPs on human health and environment has attracted particular attention. Unfortunately, the results of the large number of studies on the toxicity of TiO 2 -NPs differ significantly, mainly due to an incomplete characterization of the used nanomaterials in terms of size, shape and crystalline structure and to their unknown state of agglomeration/aggregation. The purpose of our project entitled NanoBioMet is to investigate if interferences between nanoparticles and metal homeostasis could be observed and to study the toxicity mechanisms of TiO 2 -NPs with well-characterized physicochemical parameters, using proteomic and molecular approaches. A perturbation of metal homeostasis will be evaluated upon TiO 2 -NPs exposure which could generate reactive oxygen species (ROS) production. Moreover, oxidative stress consequences such as DNA damage and lipid peroxidation will be studied. The toxicity of TiO 2 -NPs of different sizes and crystalline structures will be evaluated both in prokaryotic (E. coli) and eukaryotic cells (A549 human pneumocytes, macrophages, and hepatocytes). First results of the project will be presented concerning the dispersion of TiO 2 -NPs in bacterial medium, proteomic studies on total extracts of macrophages and genotoxicity on pneumocytes.
Quantum interference effects in a cavity QED system
International Nuclear Information System (INIS)
Akram, Uzma; Ficek, Z
2003-01-01
We consider the effect of quantum interference on population distribution and photon statistics of a cavity field interacting with dressed states of a strongly driven three-level atom. We analyse three coupling configurations of the cavity field to the driven atom, with the cavity frequency tuned to the outer Rabi sideband, the inner Rabi sideband and the central frequency of the 'singly dressed' three-level atom. The quantum doubly dressed states for each configuration are identified and the population distribution and photon statistics are interpreted in terms of transitions among these dressed states and their populations. We find that the population distribution depends strongly on quantum interference and the cavity damping. For the cavity field tuned to the outer or inner Rabi sidebands the cavity damping induces transitions between the dressed states which are forbidden for the ordinary spontaneous emission. Moreover, we find that in the case of the cavity field coupled to the inner Rabi sideband the population distribution is almost Poissonian with a large average number of photons that can be controlled by quantum interference. This system can be considered as a one-atom dressed-state laser with controlled intensity
In Search of Decay in Verbal Short-Term Memory
Berman, Marc G.; Jonides, John; Lewis, Richard L.
2009-01-01
Is forgetting in the short term due to decay with the mere passage of time, interference from other memoranda, or both? Past research on short-term memory has revealed some evidence for decay and a plethora of evidence showing that short-term memory is worsened by interference. However, none of these studies has directly contrasted decay and…
Interference effects of neutral MSSM Higgs bosons with a generalised narrow-width approximation
International Nuclear Information System (INIS)
Fuchs, Elina
2014-11-01
Mixing effects in the MSSM Higgs sector can give rise to a sizeable interference between the neutral Higgs bosons. On the other hand, factorising a more complicated process into production and decay parts by means of the narrow-width approximation (NWA) simplifies the calculation. The standard NWA, however, does not account for interference terms. Therefore, we introduce a generalisation of the NWA (gNWA) which allows for a consistent treatment of interference effects between nearly mass-degenerate particles. Furthermore, we apply the gNWA at the tree and 1-loop level to an example process where the neutral Higgs bosons h and H are produced in the decay of a heavy neutralino and subsequently decay into a fermion pair. The h-H propagator mixing is found to agree well with the approximation of Breit-Wigner propagators times finite wave-function normalisation factors, both leading to a significant interference contribution. The factorisation of the interference term based on on-shell matrix elements reproduces the full interference result within a precision of better than 1% for the considered process. The gNWA also enables the inclusion of contributions beyond the 1-loop order into the most precise prediction.
Synchrotron radiation interferences between small dipoles at LEP
International Nuclear Information System (INIS)
Bovet, C.; Burns, A.; Meot, F.; Placidi, M.; Rossa, E.; Vries, J. de
1997-06-01
Synchrotron Radiation interferences between small dipoles in the very low (visible) frequency range have been studied at the LEP diagnostic mini-wiggler. Their understanding allowed a substantial brightness gain by adequate layout modifications. The phenomenon is described analytically in terms of time coherence effects. This serves as a basis for further detailed numerical simulations of the experiment by means of stepwise ray-tracing, and allows precise interpretation of the spectral, polarization and intensity measurements collected at LEP. It also provides guidelines for SR diagnostic at injection energy in LHC
Exogenous sample contamination. Sources and interference.
Cornes, Michael P
2016-12-01
Clinical laboratory medicine is involved in the vast majority of patient care pathways. It has been estimated that pathology results inform 60-70% of critical patient care decisions. The primary goal of the laboratory is to produce precise and accurate results which reflect the true situation in vivo. It is not surprising that interference occurs in laboratory analysis given the complexity of some of the assays used to perform them. Interference is defined as "the effect of a substance upon any step in the determination of the concentration or catalytic activity of the metabolite". Exogenous interferences are defined as those that derive from outside of the body and are therefore not normally found in a specimen and can cause either a positive or negative bias in analytical results. Interferences in analysis can come from various sources and can be classified as endogenous or exogenous. Exogenous substances could be introduced at any point in the sample journey. The laboratory must take responsibility for the quality of results produced. It has a responsibility to have processes in place to identify and minimise the occurrence and effect contamination and interference. To do this well the laboratory needs to work with clinicians and manufacturers. Failure to identify an erroneous result could have an impact on patient care, patient safety and also on hospital budgets. However it is not always easy to recognise interferences. This review summarises the types and sources of exogenous interference and some steps to minimise the impact they have. Crown Copyright Â© 2016. Published by Elsevier Inc. All rights reserved.
Interference lithography for optical devices and coatings
Juhl, Abigail Therese
Interference lithography can create large-area, defect-free nanostructures with unique optical properties. In this thesis, interference lithography will be utilized to create photonic crystals for functional devices or coatings. For instance, typical lithographic processing techniques were used to create 1, 2 and 3 dimensional photonic crystals in SU8 photoresist. These structures were in-filled with birefringent liquid crystal to make active devices, and the orientation of the liquid crystal directors within the SU8 matrix was studied. Most of this thesis will be focused on utilizing polymerization induced phase separation as a single-step method for fabrication by interference lithography. For example, layered polymer/nanoparticle composites have been created through the one-step two-beam interference lithographic exposure of a dispersion of 25 and 50 nm silica particles within a photopolymerizable mixture at a wavelength of 532 nm. In the areas of constructive interference, the monomer begins to polymerize via a free-radical process and concurrently the nanoparticles move into the regions of destructive interference. The holographic exposure of the particles within the monomer resin offers a single-step method to anisotropically structure the nanoconstituents within a composite. A one-step holographic exposure was also used to fabricate self-healing coatings that use water from the environment to catalyze polymerization. Polymerization induced phase separation was used to sequester an isocyanate monomer within an acrylate matrix. Due to the periodic modulation of the index of refraction between the monomer and polymer, the coating can reflect a desired wavelength, allowing for tunable coloration. When the coating is scratched, polymerization of the liquid isocyanate is catalyzed by moisture in air; if the indices of the two polymers are matched, the coatings turn transparent after healing. Interference lithography offers a method of creating multifunctional self
Directory of Open Access Journals (Sweden)
Sridhar Krishnan
2007-07-01
Full Text Available This paper introduces a novel algorithm to excise single and multicomponent chirp-like interferences in direct sequence spread spectrum (DSSS communications. The excision algorithm consists of two stages: adaptive signal decomposition stage and directional element detection stage based on the Hough-Radon transform (HRT. Initially, the received spread spectrum signal is decomposed into its time-frequency (TF functions using an adaptive signal decomposition algorithm, and the resulting TF functions are mapped onto the TF plane. We then use a line detection algorithm based on the HRT that operates on the image of the TF plane and detects energy varying directional elements that satisfy a parametric constraint. Interference is modeled by reconstructing the corresponding TF functions detected by the HRT, and subtracted from the received signal. The proposed technique has two main advantages: (i it localizes the interferences on the TF plane with no cross-terms, thus facilitating simple filtering techniques based on thresholding of the TF functions, and is an efficient way to excise the interference; (ii it can be used for the detection of any directional interferences that can be parameterized. Simulation results with synthetic models have shown successful performance with linear and quadratic chirp interferences for single and multicomponent interference cases. The proposed method excises the interference even under very low SNR conditions of Ã¢ÂˆÂ’10Ã¢Â€Â‰dB, and the technique could be easily extended to any interferences that could be represented by a parametric equation in the TF plane.
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Po-Han eLin
2012-02-01
Full Text Available The change detection task has become a standard method for estimating the storage capacity of visual working memory. Most researchers assume that this task isolates the properties of an active short-term storage system that can be dissociated from long-term memory systems. However, long-term memory storage may influence performance on this task. In particular, memory traces from previous trials may create proactive interference that sometimes leads to errors, thereby reducing estimated capacity. Consequently, the capacity of visual working memory may be higher than is usually thought, and correlations between capacity and other measures of cognition may reflect individual differences in proactive interference rather than individual differences in the capacity of the short-term storage system. Indeed, previous research has shown that change detection performance can be influenced by proactive interference under some conditions. The purpose of the present study was to determine whether the canonical version of the change detection task—in which the to-be-remembered information consists of simple, briefly presented features—is influenced by proactive interference. Two experiments were conducted using methods that ordinarily produce substantial evidence of proactive interference, but no proactive interference was observed. Thus, the canonical version of the change detection task can be used to assess visual working memory capacity with no meaningful influence of proactive interference.
Lin, Po-Han; Luck, Steven J
2012-01-01
The change detection task has become a standard method for estimating the storage capacity of visual working memory. Most researchers assume that this task isolates the properties of an active short-term storage system that can be dissociated from long-term memory systems. However, long-term memory storage may influence performance on this task. In particular, memory traces from previous trials may create proactive interference that sometimes leads to errors, thereby reducing estimated capacity. Consequently, the capacity of visual working memory may be higher than is usually thought, and correlations between capacity and other measures of cognition may reflect individual differences in proactive interference rather than individual differences in the capacity of the short-term storage system. Indeed, previous research has shown that change detection performance can be influenced by proactive interference under some conditions. The purpose of the present study was to determine whether the canonical version of the change detection task - in which the to-be-remembered information consists of simple, briefly presented features - is influenced by proactive interference. Two experiments were conducted using methods that ordinarily produce substantial evidence of proactive interference, but no proactive interference was observed. Thus, the canonical version of the change detection task can be used to assess visual working memory capacity with no meaningful influence of proactive interference.
Epulis and pyogenic granuloma with occlusal interference
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Widowati Witjaksono
2005-06-01
Full Text Available In dental clinic of Hospital University Science Malaysia (HUSM, there were cases with Localized Gingival Enlargement (LGE in the oral cavity with occlusal interference. In this study, three cases were observed. They were a 13 - year- old female with fibrous lge around 31 and 32 with occlusal interference in protrusive movement due to X bite, a 15 - year – old female with pyogenic granuloma near 11 & 21 with occlusal interference due to deep bite; and a 24 – year – old female who was eight months in pregnancy with pyogenic granuloma on the 34-35 and severe generalized pregnancy gingivitis with occlusal interference in centric occlusion and lateral movement. Clinical and histopathological diagnosis of the first case showed fibrous epulis, whereas the second and third cases disclosed pyogenic granuloma. Chronic trauma of the gingiva due to occlusal interference was assumed to be the cause of those LGE in case 1 and 2, while in case 3 poor oral hygiene and chronic trauma were assumed to be the etiologic factors.
Autobiographical thinking interferes with episodic memory consolidation.
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Michael Craig
Full Text Available New episodic memories are retained better if learning is followed by a few minutes of wakeful rest than by the encoding of novel external information. Novel encoding is said to interfere with the consolidation of recently acquired episodic memories. Here we report four experiments in which we examined whether autobiographical thinking, i.e. an 'internal' memory activity, also interferes with episodic memory consolidation. Participants were presented with three wordlists consisting of common nouns; one list was followed by wakeful rest, one by novel picture encoding and one by autobiographical retrieval/future imagination, cued by concrete sounds. Both novel encoding and autobiographical retrieval/future imagination lowered wordlist retention significantly. Follow-up experiments demonstrated that the interference by our cued autobiographical retrieval/future imagination delay condition could not be accounted for by the sound cues alone or by executive retrieval processes. Moreover, our results demonstrated evidence of a temporal gradient of interference across experiments. Thus, we propose that rich autobiographical retrieval/future imagination hampers the consolidation of recently acquired episodic memories and that such interference is particularly likely in the presence of external concrete cues.
General Quantum Interference Principle and Duality Computer
International Nuclear Information System (INIS)
Long Guilu
2006-01-01
In this article, we propose a general principle of quantum interference for quantum system, and based on this we propose a new type of computing machine, the duality computer, that may outperform in principle both classical computer and the quantum computer. According to the general principle of quantum interference, the very essence of quantum interference is the interference of the sub-waves of the quantum system itself. A quantum system considered here can be any quantum system: a single microscopic particle, a composite quantum system such as an atom or a molecule, or a loose collection of a few quantum objects such as two independent photons. In the duality computer, the wave of the duality computer is split into several sub-waves and they pass through different routes, where different computing gate operations are performed. These sub-waves are then re-combined to interfere to give the computational results. The quantum computer, however, has only used the particle nature of quantum object. In a duality computer, it may be possible to find a marked item from an unsorted database using only a single query, and all NP-complete problems may have polynomial algorithms. Two proof-of-the-principle designs of the duality computer are presented: the giant molecule scheme and the nonlinear quantum optics scheme. We also propose thought experiment to check the related fundamental issues, the measurement efficiency of a partial wave function.
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Gerstacker WolfgangH
2010-01-01
Full Text Available A well-known receiver strategy for direct-sequence code-division multiple-access (DS-CDMA transmission is iterative soft decision interference cancellation. For calculation of soft estimates used for cancellation, the distribution of residual interference is commonly assumed to be Gaussian. In this paper, we analyze matched filter-based iterative soft decision interference cancellation (MF ISDIC when utilizing an approximation of the actual probability density function (pdf of residual interference. In addition, a hybrid scheme is proposed, which reduces computational complexity by considering the strongest residual interferers according to their pdf while the Gaussian assumption is applied to the weak residual interferers. It turns out that the bit error ratio decreases already noticeably when only a small number of residual interferers is regarded according to their pdf. For the considered DS-CDMA transmission the bit error ratio decreases by 80% for high signal-to-noise ratios when modeling all residual interferers but the strongest three to be Gaussian distributed.
Schubert, Martin
2012-01-01
This book develops a mathematical framework for modeling and optimizing interference-coupled multiuser systems. At the core of this framework is the concept of general interference functions, which provides a simple means of characterizing interdependencies between users. The entire analysis builds on the two core axioms scale-invariance and monotonicity. The proposed network calculus has its roots in power control theory and wireless communications. It adds theoretical tools for analyzing the typical behavior of interference-coupled networks. In this way it complements existing game-theoretic approaches. The framework should also be viewed in conjunction with optimization theory. There is a fruitful interplay between the theory of interference functions and convex optimization theory. By jointly exploiting the properties of interference functions, it is possible to design algorithms that outperform general-purpose techniques that only exploit convexity. The title “network calculus” refers to the fact tha...
Time and interference: Effects on working memory.
Botto, Marta; Palladino, Paola
2016-05-01
This study tested predictions from the time-based resource-sharing (TBRS) model with a classical verbal working memory (WM) task, where target and non-target information interfere strongly with each other. Different predictions can be formulated according to the dominant perspectives (TBRS and interference hypothesis) on the role of inhibitory control in WM task performance. Here, we aimed to trace the activation of irrelevant information, examining priming effects in a lexical decision task immediately following WM recall. Results indicate the roles of both time and interference constraints in determining task performance. In particular, the role of time available seemed crucial at the highest WM loads (i.e., 3 and 4 memoranda). These were also associated with a higher activation of no-longer-relevant information but, in this case, independently from time available for processing. © 2015 The British Psychological Society.
Interference Reduction Selected Measurement Signals of Ships
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Jan Monieta
2014-08-01
Full Text Available The paper presents problems encountered at the signal processing of mechanical values with electric methods. Depending on the measured quantity, the location of the sensors and the analysis frequency band, they are differently interferences. The article presents the results of applying the analysis of parameters of working and accompanying process marine medium speed reciprocating engines in the time, amplitude, frequency domain and wavelet analysis to select a reasonable method. The applied signal acquisition program allows you to perform some analysis of signals in different areas and the transformation of the data to other programs. The ways of interference reducing at various stages of their occurrence and analysis are presented. [b]Keywords[/b]: electrical signals, domain analysis, measurement interference
Frequent video game players resist perceptual interference.
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Aaron V Berard
Full Text Available Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT, a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning.
Frequent video game players resist perceptual interference.
Berard, Aaron V; Cain, Matthew S; Watanabe, Takeo; Sasaki, Yuka
2015-01-01
Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT), a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning.
An interference model of visual working memory.
Oberauer, Klaus; Lin, Hsuan-Yu
2017-01-01
The article introduces an interference model of working memory for information in a continuous similarity space, such as the features of visual objects. The model incorporates the following assumptions: (a) Probability of retrieval is determined by the relative activation of each retrieval candidate at the time of retrieval; (b) activation comes from 3 sources in memory: cue-based retrieval using context cues, context-independent memory for relevant contents, and noise; (c) 1 memory object and its context can be held in the focus of attention, where it is represented with higher precision, and partly shielded against interference. The model was fit to data from 4 continuous-reproduction experiments testing working memory for colors or orientations. The experiments involved variations of set size, kind of context cues, precueing, and retro-cueing of the to-be-tested item. The interference model fit the data better than 2 competing models, the Slot-Averaging model and the Variable-Precision resource model. The interference model also fared well in comparison to several new models incorporating alternative theoretical assumptions. The experiments confirm 3 novel predictions of the interference model: (a) Nontargets intrude in recall to the extent that they are close to the target in context space; (b) similarity between target and nontarget features improves recall, and (c) precueing-but not retro-cueing-the target substantially reduces the set-size effect. The success of the interference model shows that working memory for continuous visual information works according to the same principles as working memory for more discrete (e.g., verbal) contents. Data and model codes are available at https://osf.io/wgqd5/. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
RNA Interference in the Age of CRISPR: Will CRISPR Interfere with RNAi?
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Unnikrishnan Unniyampurath
2016-02-01
Full Text Available The recent emergence of multiple technologies for modifying gene structure has revolutionized mammalian biomedical research and enhanced the promises of gene therapy. Over the past decade, RNA interference (RNAi based technologies widely dominated various research applications involving experimental modulation of gene expression at the post-transcriptional level. Recently, a new gene editing technology, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR and the CRISPR-associated protein 9 (Cas9 (CRISPR/Cas9 system, has received unprecedented acceptance in the scientific community for a variety of genetic applications. Unlike RNAi, the CRISPR/Cas9 system is bestowed with the ability to introduce heritable precision insertions and deletions in the eukaryotic genome. The combination of popularity and superior capabilities of CRISPR/Cas9 system raises the possibility that this technology may occupy the roles currently served by RNAi and may even make RNAi obsolete. We performed a comparative analysis of the technical aspects and applications of the CRISPR/Cas9 system and RNAi in mammalian systems, with the purpose of charting out a predictive picture on whether the CRISPR/Cas9 system will eclipse the existence and future of RNAi. The conclusion drawn from this analysis is that RNAi will still occupy specific domains of biomedical research and clinical applications, under the current state of development of these technologies. However, further improvements in CRISPR/Cas9 based technology may ultimately enable it to dominate RNAi in the long term.
LANGUAGE AND CULTURE INTERFERENCE IN PLURILINGUAL EDUCATION
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Hackett-Jones, A.V.
2016-09-01
Full Text Available The article deals with interlingual phenomena that occur in the process of multiple language acquisition in a learning environment. The notions of language interference and transfer put forward by the theories of bilingualism, give useful insights when applied to the modern day educational trends. Language and culture interference is an important aspect to be considered with regard to teaching of plurilingual learners, whose communicative competence is formed on the basis of several linguistic and cultural systems that interact with each other and exert mutual influence.
Graded photonic crystals by optical interference holography
International Nuclear Information System (INIS)
Han, Chunrui; Tam, Wing Yim
2012-01-01
We report on the fabrication of graded photonic crystals in dye doped dichromate gelatin emulsions using an optical interference holographic technique. The gradedness is achieved by imposing a gradient form factor in the interference intensity resulting from the absorption of the dye in the dichromate gelatin. Wider and deeper photonic bandgaps are observed for the dyed samples as compared to the un-dyed samples. Our method could open up a new direction in fabricating graded photonic crystals which cannot be achieved easily using other techniques. (paper)
Inertial and interference effects in optical spectroscopy
International Nuclear Information System (INIS)
Karstens, W; Smith, D Y
2015-01-01
Interference between free-space and material components of the displacement current plays a key role in determining optical properties. This is illustrated by an analogy between the Lorentz optical model and a-c circuits. Phase shifts in material-polarization currents, which are inertial, relative to the non-inertial vacuum-polarization current cause interference in the total displacement current and, hence, variation in E-M wave propagation. If the displacement-current is reversed, forward propagation is inhibited yielding the semimetallic reflectivity exhibited by intrinsic silicon. Complete cancellation involves material currents offsetting free-space currents to form current-loops that correspond to plasmons. (paper)