Miracle-dz/UniFAR-FTUs huggingface dataset:
Response: Cohort Analysis Redux

Age-period-cohort (APC) analysis is synonymously called ‘‘cohort analysis’’ for a reason: Cohorts are conceived not only as the interaction of age with period, but as the essence of social change. This point was brought home forcefully to sociologists by Ryder (1965), who emphasized the collective biographies of cohorts and the principle of cohort succession. But cohort analysis has always had its difficulties. Duncan (1985) pointed to a conundrum of cohort analysis of archival data. On statistical grounds, it can be hard to adjudicate between ‘‘age-by-period or cohort-by-period interactions that authentically reflect the ‘climate of the period’’’ (p. 303). The distinction is important conceptually. Cohort effects reflect intercohort change, or cohort succession. Age effects reflect intracohort change. Even the idea of the APC accounting framework has drawn skepticism from leading figures in statistics, sociology, and demography. For example, Freedman (1985) viewed the search for a statistical solution to the APC problem as emblematic of the reflexive preference of sociologists for ‘‘off-the-shelf’’ regression (generalized linear) models in lieu of scientific models. There was a time when many sociologists were outspoken in the belief that what was required to make sociology a social science was greater reliance on statistical techniques. Sociologists who did not share that view, and who ceased reading the quantitative sociological literature, were denied the spectacle of a first-rank statistician telling sociologists that they would be far better served by serious, up-close observation and theorizing about the phenomena we purport to study (Freedman 1991).
An optical nanoantenna made of plasmonic chain resonators

We propose a novel structure that behaves like an optical antenna and converts evanescent waves into propagating waves. The system comprises metallic subwavelength cylinders distributed in a dual-period array. It is illuminated by an evanescent wave generated by total internal reflection in a close interface. For particular wavelengths, the system exhibits resonances and the inhomogeneous wave is converted into propagating waves that radiate to the far field. This effect can be controlled by varying the geometrical parameters of the structure, such as the period and the inclination angle. Therefore, the transmitted intensity can be sent to a predesigned direction. This structure could be used in highly sensitive detection devices, among other applications.
Structure and Properties of Synoptic-Scale Wave Disturbances in the Equatorial Western Pacific

Abstract A compositing technique is used to obtain the average structure of 18 disturbances which traversed an area in the equatorial western Pacific during the wet season (July–September) of 1967. Principal emphasis is placed on the wave properties in the triangular area described by Ponape, Kwajalein and Eniwetok within which it was possible to measure divergence and vertical motion and to compute moisture and heat budgets. Meridional wind maxima of nearly opposite phase occurred in the lower and upper troposphere. Negative temperature deviations were found in the vicinity of the wave trough at low and high levels; positive deviations were observed at intermediate levels. Highest relative humidities occurred in the trough region. This was also the region of strongest upward motion and greatest rainfall and cloud amount. The maximum upward velocity of 2.5 cm sec−1 was found at 300 mb. Convergence was strongest in the sub-cloud layer; divergence was concentrated near 175 mb. The maximum anticyclonic vorti.
Advances in feedback control of the Rijke tube thermoacoustic instability

This paper considers methods for the feedback control of thermoacoustic oscillations. Two distinct approaches to the problem are considered. The first is robust model-based control, which involves two stages: finding a model of the system, and designing a controller based on that model. The focus is on using model reduction techniques to find a low-order, balanced model of the Rijke tube which, despite having few degrees of freedom, is useful for feedback control design purposes. The second approach uses adaptive (or self-tuning) control, which does not require a model of the system, but instead requires that it meets some general properties. The focus here is on reducing how much must be known a priori about the plant. Specifically, an adaptive controller is considered which does not require knowledge of the sign of the plant's high-frequency gain, and this is done by employing a Nussbaum gain. The controllers are successfully applied in experiments on a Rijke tube. Both controllers completely eliminate .
Simulation of beam compression for heavy-ion fusion

Summary form only given. Recent theoretical work to model the final longitudinal and radial compression of a HIF beam is summarized in this paper. The three-dimensional electrostatic particle-in-cell (PIC) code WARP3d is used to study beam transport in the drift-compression section, while transport in the fusion chamber is modeled in using the electromagnetic PIC code LSP. Possible low-energy near-term experiments are investigated, as well as full-scale fusion drivers, and for each accelerator category, we examine how transport and error sensitivity scale with the major beam and lattice parameters.
Selective-field-ionization dynamics of a lithium m=2 Rydberg state: Landau-Zener model versus quantal approach

The selective-field-ionization (SFI) dynamics of a Rydberg state of lithium with magnetic quantum number m=2 is studied in detail based on two different theoretical models: (1) a close coupling integration of the Schroedinger equation and (2) the multichannel (incoherent) Landau-Zener (MLZ) model. The m=2 states are particularly interesting, since they define a border zone between fully adiabatic (m=0,1) and fully diabatic (m>2) ionization dynamics. Both sets of calculations are performed up to, and above, the classical ionization limit. It is found that the MLZ model is excellent in the description of the fully diabatic dynamics while certain discrepancies between the time dependent quantal amplitudes appear when the dynamics become involved. Thus, in this region, the analysis of experimental SFI spectra should be performed with care.
Precision measurement beyond the shot-noise limit.

Improvements in precision beyond the limit set by the vacuum state or zero-point fluctuations of the field are reported for two optical experiments. Both experiments employ the squeezed light from an optical parametric oscillator to reduce the level of fluctuations in one of two quadrature phase amplitudes below the shot-noise level (SNL). The first experiment follows the work of Caves1 on precision interferometry with squeezed states. An increase in signal-to-noise of 2.5 dB relative to the SNL is demonstrated for the detection of phase modulation in a Mach-Zehnder interferometer. In the second experiment amplitude modulation is encoded on a weak signal beam with an acoustooptic modulator. For the case of a squeezed signal beam compared with a beam in a coherent state, an improvement in sensitivity of 2.5 dB is achieved for the detection of amplitude changes of the field. The observed increases in sensitivity in both experiments are currently limited by simple linear losses in propagation and detection and not by the degree of available squeezing.
A deterministic approximation algorithm for the Densest k-Subgraph Problem

In the Densest k-Subgraph Problem (DSP), we are given an undirected weighted graph G = (V, E) with n vertices (v1,., vn). We seek to find a subset of k vertices (k belonging to {1,., n}) which maximises the number of edges which have their two endpoints in the subset. This problem is NP-hard even for bipartite graphs, and no polynomial-time algorithm with a constant performance guarantee is known for the general case. Several authors have proposed randomised approximation algorithms for particular cases (especially when k = n/c, c>1). But derandomisation techniques are not easy to apply here because of the cardinality constraint, and can have a high computational cost. In this paper, we present a deterministic max(d, 8/9c)-approximation algorithm for the DSP (where d is the density of G). The complexity of our algorithm is only that of linear programming. This result is obtained by using particular optimal solutions of a linear programme associated with the classical 0â€“1 quadratic formulation of DSP.
Coherent phenomena in a semiconductor quantum well system: effects of double dark states

We analyze the steady state and transient properties of the polarization and of the electronic population in a triple semiconductor quantum well structure with tunneling induced interference. We first derive the dark states of the system and show that this structure can lead to double dark states. Then, we show that under the dark state conditions the system can exhibit tunneling induced transparency, slow light, transient gain without inversion and coherent population trapping. The dynamics of the polarization and of the electronic population, as well as the total trapped electronic population in the system, are found to be depended on which dark state condition is satisfied.
Microwave Imaging of Parallel Perfectly Conducting Cylinders Using Real-Coded Genetic Algorithm Coupled With Newton-Kantorivitch Method - Abstract

Microwave imaging of parallel perfectly conducting cylinders using scattering data with or without the effect of random noise is considered in this paper. A novel algorithm, the real-coded genetic algorithm coupled with Newton-Kantorivitch method (RGA-NKM) is proposed to deal with it with significantly improved performance. The main idea of the RGA-NKM is to perform a Newton-Kantorivitch type search for the local optimum after the genetic operations in each genetic evolution. Numerical results and comparisons with both real-coded genetic algorithm (RGA) and Newton-Kantorivitch method (NKM) demonstrate that although the simplicity of RGA is lost, the search ability is greatly improved and the convergence is sped up significantly while those merits of RGA such as high level of robustness, versatility and insensitiveness to ill-posedness are retained.
Low damping constant for Co2FeAl Heusler alloy films and its correlation with density of states

Gilbert damping for the epitaxial Co2FeAl Heusler alloy films was investigated. Gilbert damping constant for the films was evaluated by analyzing the data of ferromagnetic resonance measured at the frequency of 2–20 GHz. Gilbert damping constant for the film without annealing was rather large, while it decreased remarkably with postannealing. Gilbert damping constant for the film annealed at 600 °C was ≃0.001. These behavior of Gilbert damping constant can be well explained by the fact that the density of states calculated from first principles decreases with increasing the degree of B2 order.
Force-free pulsar magnetosphere: instability and generation of magnetohydrodynamic waves

Context. Magnetohydrodynamic (MHD) instabilities can play an important role in the structure and dynamics of the pulsar magnetosphere. Aims. We consider the instability caused by differential rotation that is suggested by many theoretical models. Methods. Stability is considered by means of a linear analysis within the frame of the force-free MHD. Results. We argue that differentially rotating magnetospheres are unstable for any particular geometry of the magnetic field and rotation law. The characteristic growth time of instability is of the order of the rotation period. The instability can lead to fluctuations of the emission and enhancement of diffusion in the magnetosphere.
Multiple wavelet coherence analysis

We propose a method for analysis of localised relationships between multiple two-dimensional signals, or images, that naturally treats the local phase structure and local orientation of any variation in the observed images. The method is based on using several non-separable wavelet decompositions of the images. The set of mother wavelets used are optimally concentrated isotropic orthogonal wavelet functions extended to a triplet of functions using the Riesz transform, so that directional structure can be detected. The full set of triplet wavelet transform coefficients of two images can be used to extract local oscillatory components of the images present at a given spatial and scale point, and subsequently used to determine the local coherence and phase shift between the two images. The determination of the local phase and orientation involves calculating the continuous wavelet transform (CWT) of the images, then forming the scalogram matrix from these CWTs, and calculating the wavelet coherence. Robust estimates can be constructed by averaging over wavelet coefficients, extending Thomson's method to isotropically localised two-dimensional decompositions.
The study of perpendicular magnetic anisotropy in CoFeB sandwiched by MgO and tantalum layers using polarized neutron reflectometry

The perpendicular magnetic anisotropy (PMA) in CoFeB sandwiched by MgO and tantalum layers was investigated using anomalous Hall effect and polarized neutron reflectometry. It was found that a large PMA in the CoFeB above MgO layer was related to its low magnetization compared to the case of CoFeB under MgO layer. Using the sensitivity of neutrons to the absorption cross-section of boron, we unambiguously determined the depth profile of the boron distribution and showed that after annealing, most of the boron diffused to form a 2-nm-thick interface layer between the CoFeB and tantalum layers.
Bacterial biofilm mechanical properties persist upon antibiotic treatment and survive cell death

Bacteria living on surfaces form heterogeneous three-dimensional consortia known as biofilms, where they exhibit many specific properties one of which is an increased tolerance to antibiotics. Biofilms are maintained by a polymeric network and display physical properties similar to that of complex fluids. In this work, we address the question of the impact of antibiotic treatment on the physical properties of biofilms based on recently developed tools enabling the in situ mapping of biofilm local mechanical properties at the micron scale. This approach takes into account the material heterogeneity and reveals the spatial distribution of all the small changes that may occur in the structure. With an Escherichia coli biofilm, we demonstrate using in situ fluorescent labeling that the two antibiotics ofloxacin and ticarcillin—targeting DNA replication and membrane assembly, respectively—induced no detectable alteration of the biofilm mechanical properties while they killed the vast majority of the cells. In parallel, we show that a proteolytic enzyme that cleaves extracellular proteins into short peptides, but does not alter bacterial viability in the biofilm, clearly affects the mechanical properties of the biofilm structure, inducing a significant increase of the material compliance. We conclude that conventional biofilm control strategy relying on the use of biocides targeting cells is missing a key target since biofilm structural integrity is preserved. This is expected to efficiently promote biofilm resilience, especially in the presence of persister cells. In contrast, the targeting of polymer network cross-links—among which extracellular proteins emerge as major players—offers a promising route for the development of rational multi-target strategies to fight against biofilms.
Dynamic effects in iron phthalocyanine-like compounds

Abstract57Fe isotope-enriched iron phthalocyanine has been synthesized and studied by the Mössbauer spectroscopic method. The samples were investigated in the temperature range 100–350 K. Some peculiarities in atomic and molecular electronic structure fluctuations were observed. The intermediate Fe oxidation states are observed and it has been found that the rate of charge redistribution is temperature-dependent. The correlation between the temperature behavior of the isomeric shift and quadrupole splitting has been demonstrated. At elevated temperatures above 300 K, the Fe2+ oxidation number is quasistable. The alteration of Fe oxidation number is associated with fluctuations of electron charges, and the electron-accepting and electron-donating properties of surrounding ligands. The energy barriers separating Fe oxidation states have been determined. The possibility of modeling Mössbauer spectra of electron-transfer systems has been shown.
Attractor Sets and Quasi-Geostrophic Equilibrium

Abstract The attractor set of a forced dissipative dynamical system is for practical purposes the set of points in phase-space which continue to be encountered by an arbitrary orbit after an arbitrary long time. For a reasonably realistic atmospheric model the attractor should be a bounded set, and most of its points should represent states of approximate geostrophic equilibrium. A low-order primitive-equation (PE) model consisting of nine ordinary differential equations is derived from the shallow-water equations with bottom topography. A low-order quasi-geostrophic (QG) model with three equations is derived from the PE model by dropping the time derivatives in the divergence equations. For the chosen parameter values, gravity waves which are initially present in the PE model nearly disappear after a few weeks, while the quasi-geostrophic oscillations continue undiminished. The states which are free of gravity waves form a three-dimensional stable invariant manifold within the nine-dimensional phase spac.
Crowded: a crowd-sourced perspective of events as they happen

‘Crowded’ is a web-based application developed by the Defence Science & Technology Laboratory (Dstl) that collates imagery of a particular location from a variety of media sources to provide an operator with real-time situational awareness. Emergency services and other relevant agencies have detected or become aware of an event - a riot or an explosion, for instance - and its location or text associated with it. The ubiquity of mobile devices allows people to collect and upload media of the incident to the Internet, in real time. Crowded manages the interactions with online sources of media: Flickr; Instagram; YouTube; Twitter; and Transport for London traffic cameras, to retrieve imagery that is being uploaded at that point in time. In doing so, it aims to provide human operators with near-instantaneous ‘eyes-on’ from a variety of different perspectives. The first instantiation of Crowded was implemented as a series of integrated web-services with the aim of rapidly understanding whether the approach was viable. In doing so, it demonstrated how non-traditional, open sources can be used to provide a richer current intelligence picture than can be obtained alone from classified sources. The development of Crowded also explored how open source technology and cloud-based services can be used in the modern intelligence and security environment to provide a multi-agency Common Operating Picture to help achieve a co-ordinated response. The lessons learned in building the prototype are currently being used to design and develop a second version, and identify options and priorities for future development.
Techno-economic Analysis of Electrified Biogas Reforming

The world annual hydrogen demand continues to increase with a direct impact on the global CO 2 emissions. A potential solution is the production of CO 2 -neutral hydrogen (green hydrogen) using renewable resources. In addition to electrolytic hydrogen, biogenic hydrogen can increase productivity and enable the expansion of the H 2 economy for regions with low availability of solar and wind, such as central Europe. In this work, the design of a decentralized biogas-to-hydrogen process (50 Nm 3 h -1 H 2 productivity) based on an electrically heated reformer was developed. An economic analysis has established the viability of this suggested production route: the Hydrogen production price
Flow Field Investigations on a large Delta Wing using LSI and PIV

The vortex structures on the leeward side of a large delta wing have been investigated by use of laser sheet imaging (LSI) and particle image velocimetry (PIV). The measurements were carried out in a plane crosswise to the main flow direction. With LSI, the structures of the seeded flow have been visualized. With PIV, the local distribution of velocity has been derived from pictures of the tracer particles by means of digital cross-correlation. In both cases, the whole vortex system could be observed at Reynolds numbers Re > 10 000 000.
Comparison of temporal cloud variability simulated by a GCM with observations from the Nimbus-7 Satellite

This paper describes temporal cloudiness variability from Nimbus-7 satellite observations and a GCM simulation. The GCM clouds are parameterized using the cumulative normal distribution function to relate fractional cloud amount with large-scale relative humidity. The global distributions of cloudiness characteristics from both data sources are presented, including their temporal means and standard deviations. For the Nimbus-7 observations, the periods are for DJF and JJA, 1979-1985 while the simulated data are for perpetual January and July. Variances contributed by fluctuations with periods between 2.5 to 6 days, and >10 days are extracted. Both observed and simulated cloud variability fields show strong zonal dependence. High-frequency fluctuations are more predominant in the middle latitudes while low-frequency fluctuations predominate in the tropics and the polar regions. In general, unfiltered cloud variabilities are highest in regions associated with cyclolysis. The GCM performs creditably in not only simulating the seasonal means but also the variabilities in the temporal bands examined. Some reasons for the extracted cloud variability patterns at different locations and for different cloud heights are given.
Superconducting Properties of a Stoichiometric FeSe Compound and Two Anomalous Features in the Normal State

This paper reports the synthesis and superconducting behaviors of the tetragonal iron-chalcogenide superconductor FeSe. The electrical resistivity and magnetic moment measurements confirmed its superconductivity with a $T_c^{zero}$ and $T_c^{mag}$ at 9.4 K under ambient pressure. EPMA indicated the sample to have a stoichiometric Fe:Se ratio of 1:1 ($\pm$0.02). The Seebeck coefficient which was 12.3 $\mu$V/K at room temperature, changed to a negative value near 200 K, indicating it to be a two carriers material. Above $T_c$, the $\rho(T)$ curve revealed an 'S' shape. Hence $d\rho(T)/dT$, and $d^2\rho(T)/dT^2$ showed pseudogap-like behavior at $T^*$=110 K according to the resistivity curvature mapping (RCM) method for high $T_c$ cuprates. Moreover, the magnetoresistance $\rho_H(T)/\rho_{H=0}$ under a magnetic field and the Seebeck coefficient $S(T)$ revealed revealed pseudogap-like behavior near $T^*$. Interestingly, at the same temperature, 30 K, the sign of $S(T)$ and all signs of $d^2\rho(T)/dT^2$ changed from negative to positive above $T_c$.