Miracle-dz/UniFAR-FTUs huggingface dataset:
Temperature-insensitive and intensity-modulated embedded photonic-crystal-fiber modal-interferometer-based microdisplacement sensor

We propose and demonstrate a temperature-insensitive and intensity-modulated embedded photonic-crystal-fiber (PCF) modal-interferometer-based microdisplacement sensor. The embedded PCF sensor has the structure of single-mode-fiber (SMF)–PCF–SMF, with a core offset at one splice joint. With the structure embedded in a cured carbon-fiber-composite-laminate-based simple-supported beam, the applied microdisplacement can be measured by monitoring its extinction ratio variation, while the extinction ratio variation is independent of the temperature variation and bending-induced strain. The sensitivity reaches 0.0024 dB/μm, the measurement resolution reaches 42 μm, and the dynamic measurement range is within the range of 0–200 Hz.
Observations of NGC 4151 at 2 keV to 2 MeV from HEAO 1

Broad-range X-ray and gamma-ray spectra of the Seyfert galaxy NGC 4151 obtained by the UCSD/MIT and GSFC/CIT detectors of HEAO 1 are presented. For two out of the three observational epochs the best-fit model is a power law with photon index 1.6 + or - 0.1 in the 2 keV-2 MeV spectral range. The third observation, in June, 1978, when the intensity was a factor of 2 higher, requires a change above 50 keV from a similar power law to a steeper power law or an exponential. Through comparisons with previous observations, a weak correlation is found between the high-energy spectral index and the flux level. Comparison of these data and other X-ray and gamma-ray observations with the spectra expected from several possible emission mechanisms supports a synchrotron-self-Compton model using infrared target photons or a Compton-scattering process involving X-rays of less than 10 keV energies.
Monte Carlo Simulation Studies

This paper reviews the use of the monte carlo method to help illuminate various issues in the area of multidimensional scaling. Both two-way and three- way multidimensional scaling models and procedures are considered. Sampling distribution studies, studies comparing different procedures, and studies that have examined the basic capabilities of the methods under a variety of conditions are reviewed. Based upon the simulations, recommendations are given regarding several problems that face the user of multidimen sional scaling techniques, for example, choosing a computer program, deciding upon the appropriate di mensionality or whether useful structure exists in the data, and dealing with large stimulus sets. Practical advice is given regarding the use of several computer programs, including M-D-SCAL, TORSCA, SSA-I, KYST, MINISSA-I, INDSCAL, ALSCAL, and MULTISCALE, as well as traditional Young-House holder-Torgerson scaling.
A numerical simulation of two-dimensional radiative equilibrium in magnetostatic flux tubes. II: Computational results

We apply a recently developed numerical procedure for obtaining self-consistent radiative and mechanical equilibria of solar magnetostatic flux tubes. The tubes are modeled as localized but continuous field concentrations in a two-dimensional slab geometry, and the radiation is treated in the LTE limit. The reduced opacities in the tube (stemming from the lower gas pressures required for mechanical force balance) lead to the lateral intrusion of radiative flux into the tube, with subsequent modification of the internal atmosphere
Strong convergence of an iterative method for non‐expansive mappings

Let E be a real reflexive Banach space having a weakly continuous duality mapping Jφ with a gauge function φ, and let K be a nonempty closed convex subset of E. Suppose that T is a non‐expansive mapping from K into itself such that F (T) ≠ ∅︁. For an arbitrary initial value x0 ∈ K and fixed anchor u ∈ K, define iteratively a sequence {xn } as follows:
Effect of periodic horizontal gradients on the retrieval of atmospheric profiles from occultation measurements

Spherical symmetry is generally assumed during the retrieval process of atmospheric profiles from occultation measurements. The existence of periodic horizontal gradients, occurring on scales comparable to the distances traveled by the rays around their tangent point, is produced by gravity waves. These waves can introduce density perturbations of up to 1 or 2% in amplitude and affect the retrieved parameters accordingly. We show the consequences of ignoring these gradients in the retrieved refractivity profiles when spherical symmetry is assumed. We find that only the waves, with horizontal wavelengths close to the horizontal distance that rays travel in their final 6 or 8 km in the vertical before they are tangent in the atmosphere, will have an influence on the retrieved profiles by introducing a phase delay in the local profile of the retrieved refractivity. The horizontal wavelength of these waves corresponds to the minimum horizontal resolution associated with the retrieved profiles. We also find that smaller scale waves do not have any significant impact on the retrieved profiles, as their contribution cancels out by averaging through the periodic perturbation, while waves with very long horizontal wavelengths are in good agreement with a local spherical symmetry assumption.
Vortex methods for high-resolution simulations of viscous flow past bluff bodies of general geometry

Recent contributions to the 2-D vortex method are presented. A technique to accurately redistribute particles in the presence of bodies of general geometry is developed. The particle strength exchange (PSE) scheme for diffusion is modified for particles in the vicinity of the solid boundaries to avoid a spurious vorticity flux during the convection/PSE step. The scheme used to enforce the no-slip condition through the vorticity flux at the boundary is modified in a way that is more accurate than in the previous method. Finally, to perform simulations with nonuniform resolution, a mapping of the redistribution lattice is also used. In that case, the PSE is still done in the physical domain, using a symmetrized, conservative scheme. The quadratic convergence of this scheme is proved mathematically, and numerical tests are shown to support the proof. These elements are all validated on the benchmark problem of the flow past an impulsively started cylinder, High-resolution, long-time simulations of the flow past other bluff bodies are also presented: the case of a square and of a capsule at angle of attack. (C) 2000 Academic Press.
Load Sequence and Structure‐Foundation Interaction

Interaction between a framed structure and the foundation and soil beneath it are known to influence the distribution of load between columns and the differential settlements. Most previous studies of this phenomenon have assumed that the frame is complete before any loading occurs. However in many cases, significant load will be applied progressively during the construction of the frame. This paper examines the effect that such a change from the usual assumption will have on the interaction effects. This problem has been examined both for a plane frame and a three‐dimensional frame, and the relationship between these two sets of results is examined.
Solving Measurement Problems with an Answer-Until-Correct Scoring Procedure

Answer-until-correct (AUC) tests have been in use for some time. Pressey (1950) pointed to their ad vantages in enhancing learning, and Brown (1965) proposed a scoring procedure for AUC tests that appears to increase reliability (Gilman & Ferry, 1972; Hanna, 1975). This paper describes a new scoring procedure for AUC tests that (1) makes it possible to determine whether guessing is at ran dom, (2) gives a measure of how "far away" guess ing is from being random, (3) corrects observed test scores for partial information, and (4) yields a mea sure of how well an item reveals whether an ex aminee knows or does not know the correct re sponse. In addition, the paper derives the optimal linear estimate (under squared-error loss) of true score that is corrected for partial information, as well as another formula score under the assumption that the Dirichlet-multinomial model holds. Once certain parameters are estimated, the latter formula score makes it possible to correct for partial infor mation using only the examinee's usual number- correct observed score. The importance of this for mula score is discussed. Finally, various statistical techniques are described that can be used to check the assumptions underlying the proposed scoring procedure.
Energetic Neutral Atoms from the Heliosheath

We present the measurement and analysis of hydrogen energetic neutral atoms (ENAs) recorded with the NPD sensor of the ASPERA-3 instrument on board Mars Express during the cruise phase and the Mars orbit phase. We conclude that the origin of these ENAs is the inner heliosheath. The ENA energy spectra are all very similar and can be fitted well by a two-component power law. The ENA intensities, integrated from 0.3 to 10 keV, vary in the range of 5 × 103 to 3 × 104 cm−2 sr−1 s−1. This report is an update of our earlier paper using the final NPD calibration data and improved sensor knowledge from two years of NPD operation. The present ENA measurements fit together well with earlier ENA data that were obtained from other spacecraft at higher energies, and which also have their likely origin in the inner heliosheath. Comparison of the measured ENA energy spectra with results from several heliospheric models shows that some of these models predict significantly lower ENA intensities at Earth orbit.
The separation of a viscous liquid at a straight edge

It is well known that a first approximation to the flow of a viscous liquid in the neighbourhood of a boundary with a corner may be obtained by solving the linearized equations of momentum neglecting the inertia terms. This has been done by Dean and Montagnon [1] for the plane steady flow near a corner formed by two inclined planes. The following is a similar analysis of the modes by which a liquid can form a free surface starting at the edge of a rigid boundary. The formulation differs from that of Dean and Montagnon mainly in that the angle at which the free surface is formed is in the first place unspecified and has to be determined from the analysis.
Energy conservation, time-reversal invariance and reciprocity in ducts with flow

A sound wave propagating in an inhomogeneous duct consisting of two semi-infinite uniform ducts with a smooth transition region in between and which carries a steady flow is considered. The duct walls may be rigid or compliant. For an irrotational sound wave it is shown that the three properties of the title are closely related, such that the validity of any two implies the validity of the third. Furthermore it is shown that the three properties are fulfilled for lossless locally reacting duct walls provided the impedance varies at most continuously. For piecewise-continuous wall properties edge conditions are essential. By an analytic continuation argument it is shown that reciprocity remains true for walls with loss. For rotational flow, energy conservation theorems have been derived only with the help of additional potential-like variables. The inter-relation between the three properties remains valid if one considers these additional variables to be known. If only the basic gasdynamic variables in both half-ducts are known, one cannot formulate an energy conservation equation; however, reciprocity is fulfilled.
Intersections of algebraic and algebroid varieties

Introduction. The object of this paper is to provide a local theory for the intersection multiplicities of algebraic varieties. The notion of intersection multiplicity of two ajgebraic varieties has been for the first time put on a solid base by van der Waerden. We consider the present step as an improvement on the van der Waerden theory for the following reasons: (1) Esthetically, it seems natural to connect the multiplicity of a component M of the intersection of two varieties U and V with the local properties of V and V in the neighbourhood of M. '(2) Our theory includes an intersection theory for algebroid varieties. (3) The theory of van der Waerden fails to attribute a multiplicity to a component M of the intersection of U and V in the case where, although M has the suitable dimension, some other components have too high dimensions. The starting point of our considerations has been the observation that the multiplicity of the origin 0 in the intersection of two curves/(X, F)=0, g(X, Y)=0 may be defined to be the degree of the field extension K{(X, Y))/K((f, g)), where K((X, Y)) is the field of quotients of the ring of power series in X, Y with coefficients in the basic field K, and where K((j, g)) is the field of quotients of the ring of those power series in X, Y which can be expressed as power series in / and g. From there, I was led to the definition of multiplicity of a local ring with respect to a system of parameters, and then to the general notion of intersection multiplicity. In order to achieve this generalization, I have made extensive use of the notion of local ring, introduced by Krull. This paper is divided into three parts. Part I contains some algebraic preparations. It is concerned with the study of the properties of a certain class of local rings, which I have called geometric local rings. The most important results in this first part are: (1) what I have called the theorem of transition (§4, p. 22), because it is the tool by the use of which we can reduce questions of intersection multiplicities for algebraic varieties to similar questions for algebroid varieties; (2) the associativity formula for multiplicities in local rings which is the source not only of the associativity formula for intersections, but of most other properties of intersection multiplicities as well.
High‐current AlInN/GaN field effect transistors

We present a study on AlInN/GaN field effect transistors (FETs) grown by metalorganic chemical vapor phase epitaxy. AlInN can be grown lattice‐matched to GaN with an In concentration of 18%. In this study samples with In concentrations ranging from 9.5 to 24%, covering a range from tensely to compressively strained AlInN layers, were grown on GaN layers on Si(111). From Hall effect and capacitance‐voltage measurements we find high sheet carrier densities for most of the samples indicating a high electron density at the AlInN/GaN heterointerface. This is also reflected in the behavior of processed FETs. Nearly lattice‐matched structures show sheet carrier densities of 3.2 × 1013 cm–2 and mobilities up to ∼406 cm2/Vs. Such Al0.84In0. 16N FETs have maximum DC currents of 1.33 A/mm for devices with 1 µm gate length and 100 µm gate width and an output power of 2.5 W/mm at 2 GHz. The best devices with In concentrations of 19% show maximum output powers of 4.1 W/mm at 2 GHz. In contrast to that a compressively strained AlInN layer with an In concentration of 24% leads to a decreased polarization charge at the heterointerface and a low DC current of ∼70 mA/mm. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The abundances of nearby red clump giants

Based on the analysis of high-resolution spectra with a high signal-to-noise ratio, we have determined the abundances of the α-elements O, Si, Ca and Ti, the iron peak elements V, Fe and Ni, and the heavy element Ba without the consideration of non-local thermodynamic equilibrium (NLTE) effect and the light neutron-rich elements Na, Mg and Al with an NLTE analysis for 63 nearby red clump giants. Fe abundances cover a logarithmic range between -0.60 and +0.35 relative to solar. All abundance ratios with respect to Fe are similar to those found in the Sun. Hyperfine structure (HFS) was taken into account when calculating V lines. The difference in abundances obtained with and without HFS can be as large as 0.5 dex.
Radiation Profiles in Extended Water Clouds. I: Theory

Abstract A detailed multiple-scattering model has been employed to investigate the sensitivity of radiation profiles and flux divergences to changes in macrostructure and microstructure of basic water cloud types. The study has been performed on a range of cloud types including variable distributions of liquid water content (LWC) and drop-size distributions. Total shortwave heating rates vary from 1 to 5°C h−1 and are larger in higher clouds. IR cooling rates in the upper regions of cloud also increase with increasing elevation and are dominated by the atmospheric window contribution. Thus the typical instrument discriminating the IR radiation between 7 and 14,μm will measure almost the entire IR radiative cooling or heating of low-level water clouds. Both shortwave heating and IR cooling within cloud layers are primarily dependent on LWC and its vertical distribution and are more or less independent of drop-size distribution. Cloud albedo does vary with drop-size distribution but is virtually independent.
Application of the envelope and wavelet transform analyses for the diagnosis of incipient faults in ball bearings

Abstract Fatigue faults on the surface of rolling bearing elements are some of the most frequent causes of malfunctions and breakages of rotating machines. In normal operating conditions this kind of damage can be revealed by classical vibration analyses, such as Spectral or Envelope ones. Furthermore, this last technique—by working in time domain—makes it possible to monitor the longitudinal dimension of the defect. In this paper, the limits of the mentioned methodologies are presented by showing their application to bearings affected by different pitting failures on the outer or inner race or a rolling element and subjected to a very low radial load. Results are compared with that obtained by an advanced signal processing method based on the evaluation of the wavelet transform. Effects of fault evolution are investigated.
Estimation of Controlled Direct Effects in the Presence of Exposure-Induced Confounding and Latent Variables

Estimation of the direct effect of an exposure on an outcome requires adjustment for confounders of the exposure–outcome and mediator–outcome relationships. When some of the latter confounders have been affected by the exposure, then standard regression adjustment is prone to possibly severe bias. The use of inverse probability weighting under so-called marginal structural models has recently been suggested as a solution in the psychological literature. In this article, we show how progress can alternatively be made via G-estimation. We show that this estimation method can be easily embedded within the structural equation modeling framework and could in particular be used for estimating direct effects in the presence of latent variables. Moreover, by avoiding inverse probability weighting, it accommodates the typical problem of unstable weights in the alternative estimation approaches based on marginal structural models. We illustrate the approach both by simulations and by the analysis of a longitudinal study in individiduals who ended a romantic relationship. In this example we explore whether the effect of attachment anxiety during the relationship on mental distress 2 years after the breakup is mediated by rumination or not.
LOW POWER AND LOW COMPLEXITY CONSTANT MULTIPLICATION USING SERIAL ARITHMETIC

The main issue in this thesis is to minimize the energy consumption per operation for the arithmetic parts of DSP circuits, such as digital filters. More specific, the focus is on single- and multiple-constant multiplication using serial arithmetic. The possibility to reduce the complexity and energy consumption is investigated. The main difference between serial and parallel arithmetic, which is of interest here, is that a shift operation in serial arithmetic require a flip-flop, while it can be hardwired in parallel arithmetic. The possible ways to connect a certain number of adders is limited, i.e., for single-constant multiplication, the number of possible structures is limited for a given number of adders. Furthermore, for each structure there is a limited number of ways to place the shift operations. Hence, it is possible to find the best solution for each constant, in terms of complexity, by an exhaustive search. Methods to bound the search space are discussed. We show that it is possible to save both adders and shifts compared to CSD serial/parallel multipliers. Besides complexity, throughput is also considered by defining structures where the critical path, for bit-serial arithmetic, is no longer than one full adder. Two algorithms for the design of multiple-constant multiplication using serial arithmetic are proposed. The difference between the proposed design algorithms is the trade-offs between adders and shifts. For both algorithms, the total complexity is decreased compared to an algorithm for parallel arithmetic. The impact of the digit-size, i.e., the number of bits to be processed in parallel, in FIR filters is studied. Two proposed multiple-constant multiplication algorithms are compared to an algorithm for parallel arithmetic and separate realization of the multipliers. The results provide some guidelines for designing low power multiple-constant multiplication algorithms for FIR filters implemented using digit-serial arithmetic. A method for computing the number of logic switchings in bit-serial constant multipliers is proposed. The average switching activity in all possible multiplier structures with up to four adders is determined. Hence, it is possible to reduce the switching activity by selecting the best structure for any given constant. In addition, a simplified method for computing the switching activity in constant serial/parallel multipliers is presented. Here it is possible to reduce the energy consumption by selecting the best signed-digit representation of the constant. Finally, a data dependent switching activity model is proposed for ripple-carry adders. For most applications, the input data is correlated, while previous estimations assumed un-correlated data. Hence, the proposed method may be included in high-level power estimation to obtain more accurate estimates. In addition, the model can be used as cost function in multiple-constant multiplication algorithms. A modified model based on word-level statistics, which is accurate in estimating the switching activity when real world signals are applied, is also presented.
Rossby Wave Breaking and Transport between the Tropics and Extratropics above the Subtropical Jet

AbstractRossby wave breaking is an important mechanism for the two-way exchange of air between the tropical upper troposphere and lower stratosphere and the extratropical lower stratosphere. The authors present a 30-yr climatology (1981–2010) of anticyclonically and cyclonically sheared wave-breaking events along the boundary of the tropics in the 350–500-K potential temperature range from ECMWF Interim Re-Analysis (ERA-Interim). Lagrangian transport analyses show net equatorward transport from wave breaking near 380 K and poleward transport at altitudes below and above the 370–390-K layer. The finding of poleward transport at lower levels is in disagreement with previous studies and is shown to largely depend on the choice of tropical boundary. In addition, three distinct modes of transport for anticyclonic wave-breaking events are found near the tropical tropopause (380 K): poleward, equatorward, and symmetric. Transport associated with cyclonic wave-breaking events, however, is predominantly poleward.