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The purpose of the present paper is to investigate the flow and heat transfer of a double fractional Maxwell fluid with a second order slip model. The fractional governing equations are solved numerically by using the finite difference method. By comparing the analytical solutions of special boundary conditions, the validity of the present numerical method is examined. The effects of the two slip parameters and the fractional parameters on the velocity and temperature distribution are presented graphically and discussed. The results reveal that the fractional Maxwell fluid exhibits a stronger viscosity or elasticity for different fractional parameters, and the oscillation phenomenon will gradually decrease as expected with an increase in slip parameters.

The neural baroreflex, which regulates mean arterial pressure (MAP) via the action of the brain, consists of baroreceptors which measure MAP, and actuators that can produce a change in MAP, such as the heart and parts of the peripheral resistance containing innervated smooth muscle. The brain is the controlling unit, maintaining an appropriate MAP in spite of various disturbances. Under certain circumstances, including haemorrhage and other states of distress, the gain of the neural baroreflex can change, causing low frequency (LF) oscillations (sometimes termed Mayer waves) in blood pressure (BP). Though their purpose is unclear, the origins of these LF oscillations has previously been explained via a nonlinear feedback model, though focusing on the peripheral resistance as an MAP actuator only. The present paper now includes analytical and simulation results explaining the LF oscillation phenomenon for the full neural baroreflex, containing both peripheral resistance (PR) and cardiac branches. However, the main contribution of the paper is to examine the effect of blood pulsatility, or a lack of pulsatility, on the neural baroreflex, and how it's effect can manifest in the presence of LF oscillations. This may have importance in cases where pulsatility is reduced (for example where left-ventricular assist devices are present), or completely absent (for example in turbine-based artificial hearts).

Oscillation is a day-to-day phenomenon. When you take little children into the park and they go on the swing, the swing goes back and forth and that is called oscillation. The swing oscillates because of the force of gravity pulling it down when it stops at its highest point. Without the force of gravity, the swing, once pushed, instead of oscillating back and forth would just go around the pole in big circles with the strings remaining rigid. That would not be much fun since the child sitting on the swing would be upside down at the top, but would not come down, since there would be no gravitational force to pull him or her down. There always has to be some force for the oscillation to take place. Thus, just like gravitational force makes the swing go back and forth and makes it oscillate, it follows that any oscillation phenomenon is an indication of the existence of a force of some kind.

First results on the energy spectrum and flux of reactor antineutrinos as a function of the distance L from the reactor core, measured in the Neutrino-4 experiment for 6 < L < 12 m, are presented. The flux L‑dependence fits to the 1/L2 form with a statistical significance of ~10% corresponding to 1.64σ, so that the measured spectrum deviates from the 1/L2 law at a confidence level ~90%. The measured energy spectrum deviates from the predicted one at a similar confidence level ~90%. That both deviations are best described with oscillation parameters in the same regions of $$\Delta m_{{14}}^{2} \approx 0.7{\text{-}}0.8$$ eV2and $${{\sin }^{2}}2{{\Theta }_{{14}}} \approx 0.10{\text{-}}0.15$$ boosts the overall confidence level to ~95% (2σ). These results suggest that antineutrinos oscillate to a sterile state, but still fall short of reliably establishing the oscillation phenomenon. At present, the possibility of mimicking the oscillation effect by systematic errors cannot be completely excluded.

To investigate the oscillation phenomenon caused by renewable energy integration, the ac-side perturbation characteristics of voltage-source converter (VSC) is studied qualitatively and quantitatively. Firstly, the propagation path of the ac-side perturbation in VSC is qualitatively analyzed. And the dq component asymmetry concept is introduced in the analyzing process, which illustrates the appearance of the complementary frequency perturbation component. Then, the quantitative relationship among the perturbation components in VSC is analyzed, specially considering the influence of the phase-locked loop (PLL). Finally, the port-impedance and the complementary frequency effect admittance of VSC are deduced, which are further verified by time-domain simulation. In addition, the influence of controller parameters on the port-impedance is also analyzed in the case study. It is concluded that the complementary frequency perturbation component is mainly caused by the PLL perturbation. And the PI parameters of PLL have a great influence on the port-impedance.

Epidemic spreading has been widely investigated over the past decades. And voluntary vaccination has been often utilized to explore dynamical process in epidemics where vaccines are available. In this letter, we establish a framework considering conformity motivated update as well as myopic best response motivated update on a family network which is demonstrated by a two-layered network. Extensive numerical simulations are conducted to study the dynamics of epidemic spreading under the aforementioned update rules, from which we discover the oscillation phenomenon under the pure myopic best response condition and the amplitude diversification phenomenon under the mixing of conformity and myopic best response motivated conditions. Moreover, we find that smaller overlapping fraction of links on two-layered network shall promote the epidemic propagation. The current findings can shed some lights on the evolution of epidemic spreading process in the real-world scenarios.

The oscillation phenomenon during droplet spreading on solid surface is studied. Simulations based on the lattice Boltzmann method with the mass processed by the volume of fluid show that the oscillation continues during the whole spreading process and the maximum oscillation value occurs at the initial phase. By observing the amplitude of droplet contour volume and liquid membrane velocity, the amplitude change is obtained. The influence of droplet characteristics on amplitude is studied. Simulated results show that the effect of kinematic viscosity on droplet oscillation is greater than that of droplet surface tension. The velocity vectors inside the droplet are also tracked to understand the oscillation.

For incidence in the critical region, the propagation of gaussian lasers through triangular dielectric blocks is characterized by the joint action of angular deviations and lateral displacements. This mixed effect, known as composite Goos-Haenchen shift, produces a lateral displacement dependent on the axial coordinate, recently confirmed by a weak measurement experiment. We discuss under which conditions this axial lateral displacement, which only exists for the composite Goos-Haenchen shift, presents an oscillatory behavior. This oscillation phenomenon shows a peculiar behavior of light for critical incidence and, if experimentally tested, could stimulate further theoretical studies and lead to interesting optical applications., 12 pages, 4 figures

The purpose of this article is to study the system dynamics model and startup behavior of loop heat pipe. A mathematical model in normal operation was derived from the experimental data. The model is presented as a matrix of second-order transfer functions. It is found that the system dynamics of a LHP is a variable-structure system that changes with operating conditions. The startup phenomena are studied experimentally. The startup phenomena of a LHP can be classified into four modes, based on the heat load: (1) failure mode: Q ˙ in Q ˙ min , (2) oscillating mode: Q ˙ min Q ˙ in Q ˙ crit , (3) overshoot mode: Q ˙ crit Q ˙ in Q ˙ s , and (4) normal mode: Q ˙ s Q ˙ in . For heat load Q ˙ in 40 W ( Q ˙ s ) , the overshoot phenomenon is observed. For 20 W ( Q ˙ crit ) Q ˙ in 40 W ( Q ˙ s ) , the oscillation phenomenon is observed. For Q ˙ in 5 W ( Q ˙ min ) , the startup failure is observed. All the startup behavior is of second- order.

A magnetic horn system to be operated at a pulsed current of 320 kA and to survive high-power proton beam operation at 750 kW was developed for the T2K experiment. The first set of T2K magnetic horns was operated for over 12 million pulses during the four years of operation from 2010 to 2013, under a maximum beam power of 230 kW, and $6.63\times10^{20}$ protons were exposed to the production target. No significant damage was observed throughout this period. This successful operation of the T2K magnetic horns led to the discovery of the $\nu_{\mu}\rightarrow\nu_e$ oscillation phenomenon in 2013 by the T2K experiment. In this paper, details of the design, construction, and operation experience of the T2K magnetic horns are described., Comment: 22 pages, 40 figures, also submitted to Nuclear Instrument and Methods in Physics Research, A

This Letter investigates the spatiotemporal evolution from a pair of like polarity solitons to chaos. We reported a particular top oscillation phenomenon occurring during the evolution which has not been noticed in previous work. The experimental observation and the numerical calculation agree with each other qualitatively.

Some temperature field results are reported of the thermocapillary flow experiments conducted on board the Space Shuttle. In the experiments oscillatory thermocapillary flows were investigated in cylindrical containers filled with silicone oil. Three different container diameters and two types of heating mode were used to study their effects on the oscillation phenomenon. An infrared imaging system recorded the oil surface temperature. A movable thermistor probe measured the fluid temperature. Numerical analysis was also performed to supplement the experiments. The results from those measurements and the analysis are presented and discussed herein.

Following the Upper Bound Method (UBM), the velocity field in a rolling process is the one that minimises the power function [W. Prager, P.G. Hodge, Theory of Perfectly Plasticity Solids, Wiley, New York, 1951]. Generally, a family of velocity fields with few parameters is studied and the velocity field which minimises the power function is the best approximation of the real one. The lower the power, the better the approximation is. This paper presents a new family of velocity fields for the UBM approach of a rolling process in plane-strain conditions (2D). That family is based on the addition by an “oscillating perturbation” to a classic velocity field whose longitudinal component is constant in the strip thickness. We show that the best field of that family gives a better approximation than the classic one. This study proves there is an oscillating part in the velocity field during the rolling process. A careful observation of the fields obtained by a finite-element method, Lam3-Tec3 (1), shows that the oscillation phenomenon is in fact really present. And the oscillations predicted by the analytical model (UBM) match the FEM results very well.

The study of numu->nutau oscillation and the explicit observation of the nutau through the identification of the final-state tau lepton ("direct appearance search") represent the most straightforward test of the oscillation phenomenon. It is, nonetheless, the most challenging from the experimental point of view. In this paper we discuss the current empirical evidence for direct appearance of tau neutrinos at the atmospheric scale and the perspectives for the next few years, up to the completion of the CNGS physics programme. We investigate the relevance of this specific oscillation channel to gain insight into neutrino physics within the standard three-family framework. Finally, we discuss the opportunities offered by precision studies of numu->nutau transitions in the occurrence of more exotic scenarios emerging from additional sterile neutrinos or non-standard interactions., 26 pages, 7 figures, to appear in NJP

Inlet buzz, a shock oscillation phenomenon in supersonic air inlets was studied both numerically and experimentally. Following a supersonic wind tunnel test, a computational analysis was implemented on the supersonic air inlet of the “S-engine” which is a sub-scaled pre-cooled turbo jet engine. In the computation, shock oscillation was observed when the mass-flow was limited. The computed frequency and amplitude showed a good agreement with those of the experiment. It was also observed that the inlet buzz was not triggered when the volume of the aft duct was smaller than a certain value.

More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum., 8 pages, 5 figures. III School on Cosmic Rays and Astrophysics August 25 to September 5, 2008 Arequipa (Peru) AIP conference proceeding

We present detailed data on the unusual angular-dependent magnetoresistance oscillation phenomenon recently discovered in a topological insulator Bi_{0.91}Sb_{0.09}. Direct comparison of the data taken before and after etching the sample surface gives compelling evidence that this phenomenon is essentially originating from a surface state. The symmetry of the oscillations suggests that it probably comes from the (111) plane, and obviously a new mechanism, such as a coupling between the surface and the bulk states, is responsible for this intriguing phenomenon in topological insulators., Comment: 5 pages, 4 figures, Proceedings manuscript for the 19th International Conference on the Application of High Magnetic Fields in Semiconductor Physics and Nanotechnology (HMF-19)

Digitized Mount Wilson sunspot data from 1917 to 1985 are analyzed to examine meridional motion and rotation properties as a function of latitude and distance (ξ) from the average latitude of activity (ξ0) in each hemisphere. Latitude dependence similar to previous results is found, but only for spot groups whose areas are decreasing from one day to the next. A previous study of active region magnetic fields, using this technique of motions as a function of the average latitude of activity, had shown meridional motions on average toward ξ0. In this analysis of spot data some evidence is seen for motion away from ξ0, with some slight evidence for faster rotation equatorward of ξ0 and slower motion poleward of ξ0, similar to the torsional oscillation phenomenon. For reasons that are not clear, both of these effects are significantly more pronounced for sunspot groups whose areas are decreasing.

We discuss results and future plans for low-energy reactions that play an important role in current nuclear astrophysics research and that happen to concentrate around the region of A=7. The 7Be(p,gamma)8B and the 3He(4He,gamma)7Be reactions are crucial for understanding the solar-neutrino oscillations phenomenon and the latter one plays a central role in the issue of cosmic 7Li abundance and Big-Bang Nucleosynthesis. We also present results regarding the host dependence of the half life of the electron-capture 7Be radio-nuclide., 8 pages, 6 figures. Proceedings of the Erice School on Nuclear Physics, 2006. To appear in: "Prog. Part. Nucl. Phys."

We have performed planar tunneling measurements on ${\mathrm{Sr}}_{3}{\mathrm{Ru}}_{2}{\mathrm{O}}_{7}$, which has a field-tuned metamagnetic quantum phase transition. Our previously reported work revealed an unusual oscillation in the tunneling magnetoresistance of junctions made on ${\mathrm{Sr}}_{3}{\mathrm{Ru}}_{2}{\mathrm{O}}_{7}$ single crystals [J. Hooper et al., Phys. Rev. Lett. 92, 257206 (2004)]. We here report further characterization of this intriguing phenomenon, revealing that the oscillation has a systematic dependence on the tunnel barrier, field orientation, and temperature. We discuss possible origins of this unusual oscillation phenomenon in light of these new experimental results.

Neutrino oscillations are treated from the point of view of relativistic first quantized theories and compared to second quantized treatments. Within first quantized theories, general oscillation probabilities can be found for Dirac fermions and charged spin 0 bosons. A clear modification in the oscillation formulas can be obtained and its origin is elucidated and confirmed to be inevitable from completeness and causality requirements. The left-handed nature of created and detected neutrinos can also be implemented in the first quantized Dirac theory in presence of mixing; the probability loss due to the changing of initially left-handed neutrinos to the undetected right-handed neutrinos can be obtained in analytic form. Concerning second quantized approaches, it is shown in a calculation using virtual neutrino propagation that both neutrinos and antineutrinos may also contribute as intermediate particles. The sign of the contributing neutrino energy may have to be chosen explicitly without being automatic in the formalism. At last, a simple second quantized description of the flavor oscillation phenomenon is devised. In this description there is no interference terms between positive and negative components, but it still gives simple normalized oscillation probabilities. A new effect appearing in this context is an inevitable but tiny violation of the initial flavor of neutrinos. The probability loss due to the conversion of left-handed neutrinos to right-handed neutrinos is also presented., Comment: version accepted for publication

We have performed numerical simulations of giant vortex structures in rapidly rotating Bose-Einstein condensates within the Gross-Pitaevskii formalism. We reproduce the qualitative features, such as oscillation of the giant vortex core area, formation of toroidal density hole, and the precession of giant vortices, observed in the recent experiment [Engels \emph{et.al.}, Phys. Rev. Lett. {\bf 90}, 170405 (2003)]. We provide a mechanism which quantitatively explains the observed core oscillation phenomenon. We demonstrate the clear distinction between the mechanism of atom removal and a repulsive pinning potential in creating giant vortices. In addition, we have been able to simulate the transverse Tkachenko vortex lattice vibrations., 5 pages, 6 figures; revised description of core oscillation, new subfigure

A partial oscillation phenomenon in a digital-controlled three-phase inverter system, which is controlled by proportional controller in synchronous rotating reference frame, is analyzed in this paper. First, the discrete-time model of the system is derived. Then, a dynamics analysis scheme for this type of system is proposed. In addition, the underlying mechanism of the partial oscillation phenomenon occurring in this system is analyzed. The factors, which will cause the partial oscillation, are exactly predicted by analytical expressions. Finally, the theoretical results are verified by both simulations and experiments. These conclusions can provide an insight into the dynamics of the system.

Vibration driven compartmentalized granular gas is capable of clustering in one of the compartments，which is an effect called Maxwell demon phenomenon. One of the keys for understanding the Maxwell demon phenomenon is establishing a flux model. Based on granular hydrodynamics，Eggers deduced a simplified flux model which has been successfully used in describing the spontaneous symmetry breaking of granular gas in the compartmentalized system，but so far has not been able to predict the oscillation phenomenon of bidisperse granular gas. Experimentally studying the flux of mono-disperse granular gas in one compartment，we modify the flux model of Eggers to fit the experimental results. The modified flux model can be extended to the bidisperse granular case，and the oscillatory state can be well obtained by this modified flux model.

An oscillation phenomenon of the low frequency reverberation intensity was observed in several shallow water reverberation experiments. This phenomenon cannot be explained by the widely used incoherent reverberation theory. In this paper, to explain the observed oscillation phenomenon, a normal mode based coherent reverberation theory is presented. The theoretical analysis and numerical results show that modal interference can cause the regular oscillation phenomenon of the low frequency reverberation intensity, and the oscillation frequency is determined by the normal mode eigen-values. A new method to estimate the bottom sound speed based on the oscillation frequency of reverberation intensity was presented in this paper. The experimental results at three different sites indicate that the bottom sound speed estimated from the oscillation frequency of reverberation intensity agrees with that inverted from Matched Field Processing (MFP) well.

Resonant self-excited oscillation phenomenon for a cable in linear shear flow was investigated by an experimental study. The so-called complete locking-on of the vortex shedding to the cable oscillation is found to be a result of synchronization of modulated Karman vortices and motion induced vortices.

The amphibian isolated eyeball mounted in the usual way in a moist dark chamber furnished with a camera shutter, in an oxygen atmosphere, was stimulated by flashes of light, 40 σ in duration, from equal areas in different regions of the spectrum and the responses recorded by the string galvanometer. The maximum response in the case of the initial positive deflection B of the electroretinogram was found to lie in the dark-adapted eye in the neighbourhood of 6350, and the maximum of the secondary elevation C in the neighbourhood of 5360 A.U. Oscillations on the curve at a slow rate (below 3 per second) are described. By experimental alterations of the condition of adaptation of the eye it is possible to conclude that the oscillation phenomenon, the B summit, and the dip between the B and C summits are together dependent on one retinal process, the C summit on another. The relations of the preliminary negative deflection A are undecided.