Miracle-dz/UniFAR-FTUs huggingface dataset:
The Resolution of TOF Low-Q Diffractometers: Instrumental, Data Acquisition and Reduction Factors

The resolution of scattering vector, Q, in small-angle neutron scattering (SANS) measurements derives from uncertainties in scattered neutron wavelength and direction. The manner in which these are manifest on broad-band time-of-flight (TOF) spectrometers at pulsed sources is different from that for instruments using monochromated sources. In TOF instruments the uncertainties arise from the TOF measurement as well as the directional uncertainties due to collimation, finite sample and detector-element size that are present in any small-angle scattering instrument. Further, data from a TOF instrument must be mapped into Q space, and the strategy used to accomplish this affects the final resolution of the measurement. Thus for TOF-SANS instruments the question of resolution is more complicated than for instruments on monochromated sources. There is considerable flexibility in TOF data acquisition and Q mapping that can be utilized to optimize for intensity and Q resolution requirements of a particular measurement. In this work, present understanding of the effects of instrument geometry, TOF data acquisition and Q mapping strategies on the precision of the measurement is outlined. The goal is to establish guidelines on the best manner in which a particular measurement can be set up. Toward this end some new aspects are presented of optimal Q-mapping procedures, the effect of inelastic scattering on the measurement, and the calculation of instrument resolution functions. Some of these ideas are tested by comparison of simulations with measurement.
The Effect of Vertical Stability on Tornadogenesis

Abstract A recent numerical study of vortex growth in a flow configuration which models the principal characteristics of a tornado cyclone (Smith and Leslie, 1978) is extended to take account of vertical stability. It is shown that for a given strength of convection and rotation (in the model, the driving effect of a ‘supercell’ updraft is simulated by an imposed body force), the intensity of the mature vortex which forms in the presence of a typical vertical gradient of potential temperature is significantly lower than that which forms in an adiabatic atmosphere. We conclude that the effects of vertical stratification on tornadogenesis may often be important and may prevent some vortices, which might otherwise do so, from establishing ground contact.
Density-Functional Theory of the Energy Gap

Bande interdite d'un isolant obtenue a partir des valeurs propres de l'equation de la fonctionnelle densite a une particule de l'etat fondamental et a partir de la correction finie due a la discontinuite de la derivee de la fonctionnelle de l'energie d'echange et de correlation. Correction exprimee en termes d'autoenergie et de potentiel d'echange et de correlation de la fonctionnelle densite. Evaluation dans le cas d'un modele a 2 ondes planes ou seul intervient l'echange
Nonlinear stability of a charged electrified viscous liquid sheet under the action of a horizontal electric field

In a recent paper [D. T. Papageorgiou and P. G. Petropoulos, J. Eng. Math. 50, 223 (2004)] we considered the linear stability of a two-dimensional incompressible leaky dielectric viscous liquid sheet surrounded by a hydrodynamically passive conducting medium, when an electric field is applied parallel to the initially flat bounding fluid interfaces. It was established that for order-one Reynolds numbers and when the dielectric permittivity ratio, ep=ein∕eout, and the electric conductivity ratio, σR=σout∕σin, satisfy epσR>1, the flow is linearly stable in the absence of an electric field. When a field is present a band of unstable long waves emerges whose size increases as the field increases (the band remains finite, that is short waves are stable, for large fields). In the present study we consider the nonlinear dynamics in the vicinity of the zero electric field bifurcation. The scalings determined from the linear stability calculations are used to derive canonical strongly nonlinear evolution equations.
The numerical solution of third‐order boundary value problems using Sinc‐collocation method

The Sinc-collocation method is presented for solving boundary value problems for nonlinear third-order differential equations. Properties of the Sinc-collocation method required for our subsequent development are given and are utilized to reduce the computation of nonlinear third-order boundary value problems to some algebraic equations. The method is computationally attractive and applications are demonstrated through illustrative examples. Copyright © 2006 John Wiley & Sons, Ltd.
Molecular cloud formation by gravitational instabilities in a clumpy interstellar medium

A dispersion relation is derived for gravitational instabilities in a medium with cloud collisional cooling, using a time-dependent energy equation instead of the adiabatic equation of state. The instability extends to much smaller length scales than in the conventional Jeans analysis, and, in regions temporarily without cloud stirring, it has a large growth rate down to the cloud collision mean free path. These results suggests that gravitational instabilities in a variety of environments, such as galactic density wave shocks, swept-up shells, and extended, quiescent regions of the interstellar medium, can form molecular clouds with masses much less than the conventional Jeans mass, e.g., from 100 to 10 million solar masses for the ambient medium, and they can do this even when the unperturbed velocity dispersion remains high. Similar processes operating inside existing clouds might promote gravitationally driven fragmentation. 29 refs.
A Study of Rain Estimation Methods from Space Using Dual-Wavelength Radar Measurements at Near-Nadir Incidence over Ocean

Abstract A question arising from the recent interest in spaceborne weather radar is what methods can be used to estimate precipitation parameters from space. In this paper, dual-wavelength airborne radar data obtained from flights conducted during 1988 and 1989 are used to compare rain rates derived from backscattering and attenuation methods. We begin with a survey of path-averaged rain rates estimated from six methods over four flights. The fairly large number of high rain-rate cases encountered during these experiments allows for the first tests of the surface-reference method applied to the low-frequency (10-GHz) data. To help interpret the results the surface reference methods are studied by means of scatterplots of the surface cross sections at the two frequencies under rain and no-rain conditions. Approximate criteria are given on combining attenuation and backscattering methods to increase the effective dynamic range of the radar. The dual-wavelength capability of the radar is also used to examine.
Observation of negative bias stressing interface trapping centers in metal gate hafnium oxide field effect transistors using spin dependent recombination

The authors combine metal oxide semiconductor (MOS) gated diode measurements and very sensitive electrically detected electron spin resonance measurements to detect and identify negative bias temperature instability (NBTI) generated defect centers in fully processed HfO2 pMOS field effect transistors. Both short and long term stressing defects are different from those generated by NBTI in Si∕SiO2 devices. The spectra generated by long term stressing differ from the short term stressing signals and are somewhat similar to those observed in plasma nitrided oxide Si∕SiO2 devices. The results suggest that NBTI defects are located in the interfacial SiO2 layer of these HfO2 devices.The authors combine metal oxide semiconductor (MOS) gated diode measurements and very sensitive electrically detected electron spin resonance measurements to detect and identify negative bias temperature instability (NBTI) generated defect centers in fully processed HfO2 pMOS field effect transistors. Both short and long term stressing defects are different from those generated by NBTI in Si∕SiO2 devices. The spectra generated by long term stressing differ from the short term stressing signals and are somewhat similar to those observed in plasma nitrided oxide Si∕SiO2 devices. The results suggest that NBTI defects are located in the interfacial SiO2 layer of these HfO2 devices.
Textured PbZr0.3Ti0.7O3 Thin Films Produced by Polymeric Precursor Method Using Microwave Oven

PbZr 0.3 Ti 0.7 O 3 (PZT) films were produced by polymeric precursor route and deposited by spin-coater technique on Pt(111)/Ti/SiO 2 /Si(100) substrates. The films were heat-treated using different furnaces: (a) a conventional furnace, at 700°C; and (b) a domestic microwave oven, at 600°C. The X-ray patterns revealed that both films are single phase and reflections were identified as belongs to the PZT phase. The intensity of these reflections showed a (111), (001) and (100) preferred orientation. Morphological and electrical characterizations showed that all samples present a rather different microstructure and both with high spontaneous polarization.
The North Atlantic Oscillation and the North Atlantic Jet Variability: Precursors to NAO Regimes and Transitions

AbstractIn this paper, precursors to the North Atlantic Oscillation (NAO) and its transitions are investigated to understand the dynamical cause of the interdecadal NAO variability from dominant negative (NAO−) events during 1950–77 (P1) to dominant positive (NAO+) events during 1978–2010 (P2). It is found that the phase of the NAO event depends strongly on the latitudinal position of the North Atlantic jet (NAJ) prior to the NAO onset. The NAO− (NAO+) events occur frequently when the NAJ core prior to the NAO onset is displaced southward (northward), as the situation within P1 (P2). Thus, the northward (southward) shift of the NAJ from its mean position is a precursor to the NAO+ (NAO−) event.This finding is further supported by results obtained from a weakly nonlinear model. Furthermore, the model results show that, when the Atlantic mean zonal wind exceeds a critical strength under which the dipole anomaly prior to the NAO onset is stationary, in situ NAO− (NAO+) events, which are events not preceded b.
Bimodal Accretion Disks: Shakura-Sunyaev Disk-Advection-dominated Accretion Flow Transitions

We show that, unlike the results presented previously in the literature, the transition from an outer Shakura-Sunyaev disk (SSD) to an advection-dominated accretion flow (ADAF) is possible for large values of the viscosity parameter α > 0.5. The transition is triggered by the thermal instability of a radiation pressure-supported SSD. The transition radius is close to the central black hole. We confirm our qualitative prediction by actually constructing global bimodal SSD-ADAF solutions.
Transverse instability of interfacial solitary waves

The linear stability of finite-amplitude interfacial solitary waves in a two-layer fluid of finite depth is examined analytically on the basis of the Euler equations. An asymptotic analysis is performed, which provides an explicit criterion of instability in the case of long-wavelength transverse disturbances. This result leads to the general statement that, when the amplitude of the solitary wave is increased, the solution becomes transversely unstable before an exchange of longitudinal stability occurs.
TOMATO COLOR CHANGES UNDER CONSTANT AND VARIABLE STORAGE TEMPERATURES: EMPIRICAL MODELS

ABSTRACT Using color data from 'Sunny' tomatoes stored under constant temperatures of 15° C, 20° C, and 25° C, relationships for Hunter Hue H, Chroma C, and Value L changes with time and temperature were derived for individual tomatoes as well as for tomato groups. Hue H was found to follow a sigmoidal curve in time with a 2nd degree polynomial in temperature for the reaction rate. Chroma C was found to be dependent on Hue H only in terms of a 6th degree polynomial in H. Value L behavior was described by a negative exponential growth curve in terms of hue H and the initial Value measurement LQ. TWO methods were devised to extend the usage of these relationships to situations where the storage temperature was varying in discrete steps.
Decelerating Boundary Layer: A New Scaling and Mixing Length Model

A model experiment has been designed in the frame of a coordinated European project called AEROMEMS. This model is a two-dimensional bump in a boundary-layer wind tunnel, which mimics the adverse pressure gradient on the suction side of an airfoil at the verge of separation. The flow is characterized mainly by hot-wire anemometry. The integral parameters and the mean velocity profiles are compared to existing models and to Navier-Stokes computations. A new scaling and a new mixing length model are proposed and validated on the Ludwig and Tillman data also
Impact of GaN cap on charges in Al2O3/(GaN/)AlGaN/GaN metal-oxide-semiconductor heterostructures analyzed by means of capacitance measurements and simulations

Oxide/semiconductor interface trap density (Dit) and net charge of Al2O3/(GaN)/AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistor (MOS-HEMT) structures with and without GaN cap were comparatively analyzed using comprehensive capacitance measurements and simulations. Dit distribution was determined in full band gap of the barrier using combination of three complementary capacitance techniques. A remarkably higher Dit (∼5–8 × 1012 eV−1 cm−2) was found at trap energies ranging from EC-0.5 to 1 eV for structure with GaN cap compared to that (Dit ∼ 2–3 × 1012 eV−1 cm−2) where the GaN cap was selectively etched away. Dit distributions were then used for simulation of capacitance-voltage characteristics. A good agreement between experimental and simulated capacitance-voltage characteristics affected by interface traps suggests (i) that very high Dit (>1013 eV−1 cm−2) close to the barrier conduction band edge hampers accumulation of free electron in the barrier layer and (ii) the higher Dit cen.
Equatorial Circumnavigation of Moisture Signal Associated with the Madden-Julian Oscillation (MJO) during Boreal Winter

In order to describe the connection from an event of MJO to the next in the boreal winter, the eastward propagation of MJO is studied, focusing on that over the western hemisphere. Propagation signal is identified by EEOF analysis, performed on the bandpass filtered OLR for the period of 1979-2000. Besides NOAA OLR, total precipitable water (TPW), and surface winds from Special Sensor Microwave/ Imager (SSM/I), precipitation observed from Microwave Sounding Unit (MSU), and reanalysis and operational analysis data of the European Centre for Medium-Range Weather Forecasts (ECMWF), are utilized for the composite. Positive TPW anomalies are found, synchronizing with tropospheric and surface zonal wind anomalies. They propagate eastward all around the equator in the boreal winter. They propagate at a speed of about 6 ms-1, with a Kelvin-Rossby coupled mode structure in the eastern hemisphere, and at about 20 ms-1 as an envelope of a radiating response in the western hemisphere. Within the envelope in the western hemisphere, faster propagating signals corresponding to 30-40 ms-1 exist in the fields of TPW, zonal wind at 200 and 700 hPa, surface zonal wind. It is especially clear in the geopotential anomalies at 1000 hPa. This fast propagation speed of 30-40 ms-1 is consistent with a first-baroclinic dry Kelvin wave mode recently rediscovered by Milliff and Madden (1996), and Bantzer and Wallace (1996). TPW increases under surface easterly anomalies along the equator. After the preceding TPW accumulation for 5-7.5 days, convective anomalies begin to occur as a part of the next cycle of the MJO from the eastern Atlantic to the western Indian Ocean. These results suggest a following conceptual model for propagations and event-to-event connections of MJO. Equatorial Kelvin wave generated by convection of the MJO propagates eastward emanating from a warm pool region at a faster speed (30-40 ms-1) in the western hemisphere. Elevated topography of the South American and African continent, blocks the wave propagation. After being blocked several days by topography, they continue to proceed. As a result, the signal propagates at 20 ms-1 on average. Frictional convergence with lower easterlies of the dry Kelvin wave results in the associated propagation of TPW positive anomaly. Although it does not induce deep convections over large-scale subsidence regions, once it enters over the warm water in the western Indian Ocean, it helps to induce active convections for the next cycle of MJO.
An Integrated Approach to Mid- and Upper-Level Turbulence Forecasting

Abstract An automated procedure for forecasting mid- and upper-level turbulence that affects aircraft is described. This procedure, termed the Graphical Turbulence Guidance system, uses output from numerical weather prediction model forecasts to derive many turbulence diagnostics that are combined as a weighted sum with the relative weights computed to give best agreement with the most recent available turbulence observations (i.e., pilot reports of turbulence or PIREPs). This procedure minimizes forecast errors due to uncertainties in individual turbulence diagnostics and their thresholds. Thorough statistical verification studies have been performed that focused on the probabilities of correct detections of yes and no PIREPs by the forecast algorithm. Using these statistics as a guide, the authors have been able to intercompare individual diagnostic performance, and test various diagnostic threshold and weighting strategies. The overall performance of the turbulence forecast and the effect of these stra.
A posteriori L ∞ ( L ∞ ) -error estimates for ﬁnite-element approximations to parabolic optimal control problems

We derive space–time a posteriori error estimates of ﬁnite-element method for the linear parabolic optimal control problems in a convex bounded polyhedral domain. The variational discretization is used to approximate the state and co-state variables with the piecewise linear and continuous functions, while the control variable is computed using the implicit relation between the control and co-state variables. The temporal discretization is based on the backward Euler method. The key feature of this approach is not to discretize the control variable but to implicitly utilize the optimality conditions for the discretization of the control variable. Our error analysis relies on the elliptic reconstruction technique introduced by Makridakis and Nochetto (SIAM J Numer Anal, 41:1585–1594, 2003) in conjunction with heat kernel estimates for linear parabolic problem. The use of elliptic reconstruction technique greatly simpliﬁes the analysis by allowing us to take the advantage of existing elliptic maximum norm error estimate and the heat kernel estimate. We derive a posteriori error estimates for the state, co-state, and control variables in the L ∞ ( 0 , T ; L ∞ (Ω)) -norm. Numerical experiments are conducted to illustrate the performance of the derived estimators.
A New Look at the Target Feedback Loop Parameterization for H ∞ /LTR Control

In this paper, a new approach on the target feedback loop (TFL) parameterization for the H ∞ /loop transfer recovery (LTR) control is presented. The proposed procedure, which is based on a similarity transformation, allows to obtainaﬁrst-ordersystembehaviorthroughaparticularshap-ing of the TFL sensitivity in terms of singular values. Furthermore, the proposed methodology makes possible to augment the design plant model with any stable real-ﬁnite pole, and not only a pole at the origin, as classical TFL parameterization procedures suggest. Thus, the proposed methodology should gather great attention by LTR-based control applications in which the use of integrators in the open-loop is undesirable or even prohibitive. Additional properties are derived if the design plant model does not have poles at the open right-half plane. Since H ∞ /LTR control can be viewed as a generalization of well-known LQG/LTR control, the proposed methodology in this paper to shape the TFL can be properly extended to the LQG/LTR control.
POSSIBILITY THEORY III: POSSIBILISTIC INDEPENDENCE

Abstract The introduction of the notion of independence in possibility theory is a problem of long-standing interest. Many of the measure-theoretic definitions that have up to now been given in the literature face some difficulties as far as interpretation is concerned. Also, there are inconsistencies between the definition of independence of measurable sets and possibilistic variables. After a discussion of these definitions and their shortcomings, a new measure-theoretic definition is suggested, which is consistent in this respect, and which is a formal counterpart of the definition of stochastic independence in probability theory. In discussing the properties of possibilistic independence, I draw from the measure- and integral-theoretic treatment of possibility theory, discussed in Part I of this series of three papers. I also investigate the relationship between this definition of possibilistic independence and the definition of conditional possibility, discussed in detail in Part II of this series. F.
Rossby-wave breaking, microbreaking, filamentation, and secondary vortex formation-The dynamics of a perturbed vortex

Abstract The behavior of an isolated vortex perturbed by topographically forced Rossby waves is studied using the method of Contour Dynamics. For a single-contour vortex a distinct forcing threshold exists above which the wave breaks in a dynamically significant way, leading to a disruption of the vortex. This breaking is distinguished from the process of weak filamentary breaking described by Dritschel and classified here as microbreaking; the latter occurs in nondivergent flow even at very small forcing amplitudes but does not affect the vortex in a substantial manner. In cases with finite Rossby deformation radius (comparable with the vortex radius) neither breaking nor microbreaking occurs below the forcing threshold. In common with previous studies using high-resolution spectral models, the vortex is not diluted by intrusion of outside air, except during remerger with a secondary vortex shed previously from the main vortex during a breaking event. The kinematics of the breaking process and of the vor.
1.3‐μm light‐emitting diode from silicon electron irradiated at its damage threshold

We report 77‐K electroluminescence from an irradiated carbon‐rich silicon diode that has an internal quantum efficiency more than 103 times higher than that of band‐to‐band recombination in an unirradiated, but otherwise identical diode. This is achieved by creating optically active Cs‐SiI‐Cs complexes with room‐temperature electron bombardment at an energy between the displacement thresholds for single vacancy and divacancy formation. Under these irradiation conditions, it is possible to create a high concentration of radiative defects without gross degradation of the diode’s electrical characteristics. The technique could provide very large scale integration‐compatible silicon light‐emitting diodes for 1.3–1.6 μm all‐silicon integrated optics.
Charge Separation Effects in the Ferraro‐Rosenbluth Cold Plasma Sheath Model

The exact relativistic treatment is given of the Ferraro‐Rosenbluth cold plasma sheath model, and is compared with the nonrelativistic solution given previously by Sestero. It is found that the anomalous solution obtained by Sestero, namely, the fact that the ions turn back before the electrons, persists in the relativistic treatment although the ion stream and electron stream are separated in space. As in the Sestero solution it is found that the over‐all charge in the sheath is not in general zero. Numerical illustrations are given for the case when the velocities are comparable with the velocities encountered in the solar wind.