Miracle-dz/UniFAR-FTUs huggingface dataset:
Error analysis for parameters determined in nonlinear least‐squares fits

This article presents a calculation of the error in parameters derived from the least‐squares method of fitting nonlinear models to experimental data. The formula reduces to the well‐known result for the case of a linear least‐squares fit. It differs, however, from a method for calculating the error that is often employed for the nonlinear case. The difference between the current result and that method’s is illustrated with examples from least‐squares fits to spectroscopic data.
3D structures using surface relief gratings of azobenzene materials

We present here a method of step-by-step 3D structure fabrication using holographic formation of surface relief gratings (SRG) in azobenzene-containing layers alternated with spacer layers. The method possesses opportunities that could not be realized by other holographic approaches, especially the variation of grating periods or the shape of the SRG in different layers (hierarchical structures), full flexibility of the structure type and parameters. One of the main problems to be solved is the compatibility of active azobenzene-containing polymers and a material for the spacer layers. We resolved the problem and found active and spacer polymers with excellent compatibility. The materials allow the preparation of films with good optical quality and the inscription of SRG with modulation amplitudes up to 1 µm in reasonable time. The refractive index difference between active and spacer polymers (currently 0.15–0.2) results in appreciable diffraction efficiency of the SRG after the application of the spacer layer. The phase correlation technique between adjacent layers has been developed. The fabrication of multilayer structures has been demonstrated by examples of a combination of linear, tetragonal and hexagonal SRG with three active layers and hierarchical structures.
Neutron Capture Reaction Rates for Silicon and Their Impact on the Origin of Presolar Mainstream SiC Grains

We have made new, improved measurements of the Si28-30 (n, gamma) cross sections and have done a resonance analysis of these data including previous total cross sections. Together with the calculated contributions due to direct capture, we calculated the astrophysical (n, gamma) reaction rates and investigated the s-process abundances of the Si isotopes. Measured isotopic anomalies of intermediate and heavy elements in SiC grains from meteorites appear to be attributable to the s-process in asymptotic giant branch (AGB) stars. But the Si isotopic ratios in these grains are substantially different than s-process models predict. Therefore, recent papers have invoked galactic chemical evolution or other effects to explain the Si isotope ratios in these grains. Our new reaction rates are significantly different than previous rates, and s-process calculations using these rates lead to much larger isotopic shifts in Si-30. However, these exploratory calculations demonstrate that even with these substantially different rates the large observed variation in SiC grain from AGB stars cannot be explained by standard s-process models.
Relativistic distorted-wave calculation of electron impact excitation of xenon

A relativistic formulation of the distorted-wave method is presented for electron impact excitation of xenon. Calculations are performed for xenon 6s(3/2)01 and 6s(1/2)01 states with both the target atom and scattered electron treated fully relativistically. The wavefunctions representing the distorted waves are fully antisymmetrized to account for electron exchange. Differential cross sections and collisional alignment and orientation parameters are presented and compared with recent experimental data. The overall agreement with experiment is very satisfactory. The occurrence of changes in the spin orientation of the scattered electron due to both exchange and relativistic effects is predicted. The possibility of experimentally observing these spin changes in the collision frame through electron-photon coincidence measurements is pointed out.
Sample-detector coupling in atomic resolution magnetic resonance diffraction

A technique for potential realization of atomic resolution magnetic resonance diffraction was recently proposed for the case of a crystalline sample in proximity of a ferromagnetic sphere [M. Barbic, J. Appl. Phys. 91, 9987 (2002)]. This article predicted the detection of distinct peaks in the number of resonant spin sites at different magnetic field values for specific sphere and crystal configurations. Here, the focus is on the specific detection coupling mechanisms between the resonant spin population of the sample and the magnetic sphere probe. We investigate and compare the force, torque, and flux detection mechanisms in order to provide guidance to the experimental efforts towards the realization of the atomic resolution magnetic resonance diffraction. We also investigate the dependence of the magnetic resonance diffraction spectrum on the relative position of the magnetic sphere with respect to the crystal lattice.
Metrics for agent observers

We present two metrics (utility functions based on observational requirements) for specifying agent behaviour in the eSTAR autonomous observing system. Together, these metrics provide an agent with tools to analyse the phase coverage and interconnectivity properties of partial datasets, and to modify the subsequent observing strategy in order to fulfill the astronomical constraints expressed by the astronomer. We discuss the behaviour of the metrics for evenly sampled and randomly sampled datasets, and present a use case that demonstrates how the metrics could be applied in an agent-based observing scenario. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Observations of C-12O/J=2-1/ emission in the Large and Small Magellanic Clouds.

We have detected /sup 12/ CO(J = 2-1) emission at three positions in the Large Magellanic Cloud, near the bright H II regions 30 Doradus, N159, and N160 A. N159 is the only object in the LMC from which CO emission was detected before. The CO(2-1) spectra of N159 and N160A show two velocity components at about V/sub hel/ = 255 km s/sup -1/ and around V/sub hel/ = 300 km s/sup -1/. Emission at the latter velocity may also be present in 30 Doradus. Four positions in the LMC and four in the SMC failed to show an unambiguous signal. Nevertheless, some emission may be present at the T(/sub A/ = 1 K(3sigma) noise level. We conclude that the 30 Doradus sector of the LMC at most is marginally deficient in CO emission, as compared to the Galaxy, whereas the SMC appears to be significantly deficient in CO with respect to both the LMC and the Galaxy
An Analysis of Variance Test for the Exponential Distribution (Complete Samples)

Procedures are developed for evaluation of various composite and simple hypotheses of exponentiality. The principles underlying these methods are similar to those used in defining and extending the W-statistic for normality (Shapiro and Wilk, 1965, 1968). The W-exponential statistic (scale and origin invariant) turns out to be the scaled ratio of the squared difference of the sample mean and smallest observation to the usual symmetric sum of squares about the mean. Procedures are developed to augment the W-exponential statistic when one or both of the location and scale parameters of the general exponential are specified. Necessary tables, some examples, and an abstract of an empirical sampling study of sensitivity are given.
Solitary wave solutions of nonlinear wave equations

A method is proposed for obtaining traveling‐wave solutions of nonlinear wave equations that are essentially of a localized nature. It is based on the fact that most solutions are functions of a hyperbolic tangent. This technique is straightforward to use and only minimal algebra is needed to find these solutions. The method is applied to selected cases.
Unified Symmetric BEM‐FEM for Site Effects on Ground Motion—SH Waves

This paper is concerned with the numerical solution of time‐harmonic transition problems in elasticity, in general, and with soil amplification in inhomogeneous alluvial valleys, in particular. A mixed variational formulation based on Hamilton's principle, involving field equations only within the valley and an integral representation for the surrounding medium, is developed and used to derive a symmetric finite element‐boundary‐element method for this problem. This method, valid for all frequencies, incorporates automatically the displacement and traction interface continuity conditions; therefore, it imposes no boundary constraints on the approximating functions. The BEM‐FEM is applied to the response of semicircular inhomogeneous valleys with linearly increasing shear modulus with depth, due to oblique incident SH waves. Numerical results emphasize the importance of two‐dimensional resonant effects in deep valleys, and the strong effects of varying stiffness on surface motion, including a rapid spatial.
Estimation, Inference and Specification Analysis: Conclusion

This book examines the consequences of misspecifications ranging from the fundamental to the nonexistent for the interpretation of likelihood-based methods of statistical estimation and interference. Professor White first explores the underlying motivation for maximum-likelihood estimation, treats the interpretation of the maximum-likelihood estimator (MLE) for misspecified probability models, and gives the conditions under which parameters of interest can be consistently estimated despite misspecification, and the consequences of misspecification, for hypothesis testing in estimating the asymptotic covariance matrix of the parameters. Although the theory presented in the book is motivated by econometric problems, its applicability is by no means restricted to economics. Subject to defined limitations, the theory applies to any scientific context in which statistical analysis is conducted using approximate models.
Turbulent mixing efficiency at an energetic ocean site

[1] The unsteady and inhomogeneous forcing of the stratified ocean leads to highly variable turbulent temperature and velocity fields, both in space and time, complicating the characterization of mixing from field measurements. Mixing rates are often inferred indirectly from measurements of turbulent kinetic energy dissipation ϵ via Osborn's model Kρ=Rf1−RfϵN2 (N is the background stratification) by assuming the flux Richardson number Rf = 0.17 is constant, despite continued debate on its relevance for environmental flows. From high-frequency velocity measurements, we estimate ϵ within meters of the continental slope and compute Kρ with three different models, which we compare to the turbulent diffusivity for heat KT derived from colocated temperature measurements. We also infer Rf by equating Osborn's relationship for Kρ to our estimated KT. Applying Osborn's model with a fixed Rf = 0.17 overpredicted mixing rates by more than an order of magnitude. The other two models, which reduce the mixing efficiency with increasing magnitude of the ratio of the Ozmidov length scale LO to the Kolmogorov length scale η, fared better than Osborn's fixed model. The best agreement (within a factor of 2) was with a model derived from laboratory experiments, at much lower turbulent Reynolds numbers ReT than our measurements, but covering a wide range of the ratio of LO/η. However, our observations correlated more strongly with the turbulent ReT than with LO/η, likely because the ReT measures the “true” separation between the largest and smallest turbulent overturns. Mixing rate predictions improved when the ReT was used instead of LO/η.
MULTICOLOR POLARIMETRY OF SELECTED BE STARS : A LONG-TERM ANALYSIS.

New observations of linear polarization in the UBVRI system for six bright northern Be stars are combined with existing measurements from two previous epochs in an analysis of long-term variation over nearly two decades. No indication of large short-term variability is found within the individual data sets, but ζ Tau and π Aqr have shown steady change on the longer time scale.
Experimental Studies of Quality Factor Deterioration in Shear-Horizontal-Type Surface Acoustic Wave Resonators Caused by Apodization of Interdigital Transducer

We investigate how the apodization applied to interdigital transducers (IDTs) affects the quality factor Q at the antiresonance frequency of surface acoustic wave (SAW) resonators. First, we fabricated SAW resonators with different apodization patterns on a SiO2/Cu/0°YX-LiNbO3 structure, and showed that the Q factor become worse when the apodization becomes steeper and the IDT aperture is narrower. Next, it was shown by optical measurement that the Q degradation is mainly due to the radiation of SH waves from the resonator. The radiation consists of energy leakage as bulk waves, diffraction, and scattering of incident SAWs, and their strength strongly depends on the steepness of the apodization pattern.
Powered partial least squares discriminant analysis

From the fundamental parts of PLS‐DA, Fisher's canonical discriminant analysis (FCDA) and Powered PLS (PPLS), we develop the concept of powered PLS for classification problems (PPLS‐DA). By taking advantage of a sequence of data reducing linear transformations (consistent with the computation of ordinary PLS‐DA components), PPLS‐DA computes each component from the transformed data by maximization of a parameterized Rayleigh quotient associated with FCDA. Models found by the powered PLS methodology can contribute to reveal the relevance of particular predictors and often requires fewer and simpler components than their ordinary PLS counterparts. From the possibility of imposing restrictions on the powers available for optimization we obtain an explorative approach to predictive modeling not available to the traditional PLS methods. Copyright © 2008 John Wiley & Sons, Ltd.
Finite-time fault-tolerant control for rigid spacecraft with actuator saturations

This study investigates the finite-time attitude-tracking problem for rigid spacecraft. A novel non-singular terminal sliding-mode control (NTSMC) law is designed to provide finite-time convergence and fast, high control precision even though inertia uncertainties and external disturbances affect the spacecraft systems under actuator failures and saturations. The proposed NTSMC scheme is chattering suppression and singularity-free. Simulation results are presented to demonstrate the efficiency of the proposed method.
The synthesis of 3D form-closure grasps

Presents a formulation of the synthesis of 3D frictional form-closure grasps of n robot fingers. First, using a recursive reduction technique, we transform the problem in 6D wrench space to one in three dimensions. Then we rewrite the sufficient and necessary condition for form-closure grasps in the equivalent form of the inconsistency of each of the two sets of linear inequalities. Then we propose three conditions to check the inconsistency of the inequality system, which geometrically indicates whether the convex region formed by the inequality system is empty. We have implemented the algorithms and confirmed their real-time efficiency for the synthesis of 3D form-closure grasps.
Dissecting galactic winds with the SAMI Galaxy Survey

Abstract We conduct a case study on a normal star-forming galaxy (z=0.05) observed by the SAMI Galaxy Survey and demonstrate the feasibility and potential of using large integral field spectroscopic surveys to investigate the prevalence of galactic-scale outflows in the local Universe. We perform spectral decomposition to separate the different kinematic components overlapping in the line-of-sight direction that causes the skewed line profiles in the integral field data. The three kinematic components present distinctly different line ratios and kinematic properties. We model the line ratios with the shock/photoionization code mappings iv and demonstrate that the different emission line properties are caused by major galactic outflows that introduce shock excitation in addition to photoionization. These results set a benchmark of the type of analysis that can be achieved by the SAMI Galaxy Survey on large numbers of galaxies.
Multifrequency VLA observations of the prototypical narrow-angle tail radio source NGC 1265

Resultats d'observations VLA de NGC 1265 a 21,6 et 2 cm. On donne des cartes des jets et des queues avec des resolutions diverses (de 0,45″ a 12″). On discute de l'intensite totale, de l'indice spectral et de la polarisation
Alpha Schottky junction energy source

Isotope batteries offer solutions for long-lived low-power sensor requirements. Alpha emitting isotopes have energy per decay 103 times that of beta emitters. Alpha particles are absorbed within 20 μm of most materials reducing shielding mitigation. However, damage to materials from the alphas limits their practical use. A Schottky Barrier Diode (SBD) geometry is considered with an alpha emitting contact-layer on a diamond-like crystal semiconductor region. The radiation tolerance of diamond, the safety of alpha particles, combined with the internal field of the SBD is expected to generate current useful for low-power electronic devices over decades. Device design parameters and calculations of the expected current are described.
Polycapillary focusing optic for small-sample neutron crystallography

The relatively low flux from neutron sources means that structural analysis using neutron diffraction requires large crystals that are often not available. The feasibility of a polycapillary focusing optic to produce a small intense spot of size < ∼0.5 mm for small crystals has been explored and such an optic has been tested both on a monochromatic and on a polychromatic beam. In a diffraction measurement from an α-quartz crystal using a 2.1° convergent beam from a pulsed neutron source, six diffraction peaks in the 1.5–4 A wavelength bandwidth transmitted by the optic were observed. These diffraction spots show an intensity gain of 5.8 ± 0.9 compared with a direct beam diffracting from the same sample volume as that illuminated by the convergent beam.
Are recent solar heavy element abundances consistent with helioseismology?

During the last decade the abundances of heavy elements in the Sun have been revised downwards leading to serious discrepancy between solar models constructed using these abundances and the available seismic data. Much of these downward revision of abundances of Oxygen and other light elements was attributed to use of improved 3D solar atmospheric models. Recently, independent 3D models have been used to calculate solar abundances of these elements and calculated values are higher than the earlier estimates also obtained using 3D atmospheric models. In this work we investigate if these revised abundances are consistent with seismic data. We also investigate whether an increase in Neon abundance can help in resolving the discrepancy.
Rational solutions of linear differential equations

Abstract Let L be a linear differential operator with rational coefficients such that 0 is not an irregular singularity of L and that for sufficiently many p's the equation Lv = 0 has no zero solution mod p. We show that if u is a formal power series whose coefficients are p-adic integers for almost all p and if Lu is rational, then u too is rational.
High mobility, dual layer, c-axis aligned crystalline/amorphous IGZO thin film transistor

We demonstrate a dual layer IGZO thin film transistor (TFT) consisting of a 310 °C deposited c-axis aligned crystal (CAAC) 20 nm thick channel layer capped by a second, 30 nm thick, 260 °C deposited amorphous IGZO layer. The TFT exhibits a saturation field-effect mobility of ∼20 cm2/V s, exceeding the mobility of 50 nm thick single layer reference TFTs fabricated with either material. The deposition temperature of the second layer influences the mobility of the underlying transport layer. When the cap layer is deposited at room temperature (RT), the mobility in the 310 °C deposited CAAC layer is initially low (6.7 cm2/V s), but rises continuously with time over 58 days to 20.5 cm2/V s, i.e., to the same value as when the second layer is deposited at 260 °C. This observation indicates that the two layers equilibrate at RT with a time constant on the order of 5 × 106 s. An analysis based on diffusive transport indicates that the room temperature diffusivity must be of the order of 1 × 10−18 cm2 s−1 with an .
On the linear and nonlinear resistive tearing-mode instabilities

The tearing-mode instabilities of Harris sheet magnetic field configuration are studied based on the numerical simulations of two-dimensional, resistive, compressible MHD models with isotropic pressure. The linear growth rate and the eigenmode structure are calculated from the linear numerical model for various parameters: magnetic Reynolds number, Rm; the ratio of wavelength to the layer thickness; magnetic By component; and plasma beta, as well as for different equations of state. The linear solutions are then used as initial perturbations of the nonlinear numerical model to allow the full evolution of resistive tearing-mode instability. The linear calculations show that for the range of Rm = 10–105 the fastest growth rate increases with decreasing Rm and only slightly increases with increasing plasma beta and By but that it is not sensitive to the equation of state. While the nonlinear calculations snow that only for large Rm, where the diffusion time is much larger than the linear growth time, the magnetic island may possibly grow substantially and become saturated. For small Rm the plasmoids either diminish in the late stage or do not have apparent growing; that is, the linear analysis is not meaningful for large resistivity cases. The calculations are compared to the magnetic island structure at Earth's magnetopause reconstructed from the single-spacecraft data by Hau and Sonnerup [1999].
The dependence of cirrus infrared radiative properties on ice crystal geometry and shape of the size‐distribution function

The concept of an effective diameter is often used to describe the radiative properties of cirrus, and is commonly applied in the retrieval of cirrus microphysical and/or macrophysical properties. In this paper the applicability of an effective‐diameter concept at thermal wavelengths (4.0–30 µm) is further investigated. It is shown that at a wavelength of 8.2 µm the concept begins to break down for small ice crystal effective diameters (≤25 µm) and has completely broken down beyond a wavelength of 20 µm. At wavelengths in the far infrared (20–30 µm) the potential impact of ice crystal geometry and assumed size‐distribution shape on brightness‐temperature measurements is quantified. It is found that the brightness‐temperature difference at a wavelength of 25 µm due to two different populations of ice crystal shapes, but with both populations having the same effective diameter and size‐distribution shape, is ∼5 K. However, if both populations have the same ice crystal shape and effective diameter but different size‐distribution shapes, then the brightness‐temperature difference is about ∼9 K at the same wavelength. The impact of size‐distribution shape on the brightness‐temperature difference is almost twice as great as that of crystal shape. Given that there is sensitivity to the shape of the size‐distribution function at far‐infrared wavelengths, the potential for retrieving size‐distribution shape using far‐infrared brightness‐temperature measurements is also investigated. The implications of these findings are that the concept of an effective diameter cannot be generally applied at infrared wavelengths unless a priori information is known about the shape of the size‐distribution function. Copyright © 2005 Royal Meteorological Society