Miracle-dz/UniFAR-FTUs huggingface dataset:
Robust adaptive decentralized control of robot manipulators

The authors proposes a robust adaptive decentralized control algorithm for trajectory tracking of robot manipulators. The controller is designed based on a Lyapunov method, which consists of a PD (proportional plus derivative) feedback part and a dynamic compensation part. It is shown that, without any prior knowledge of manipulator or payload parameters and possibly under deterioration of parameter variation with time or state-independent input disturbances, the tracking error is bound to converge to zero asymptotically. In particular, the algorithm does not require explicit system parameter estimation and therefore makes the controller structurally simple and computationally easy. Moreover, the controller is implemented in a decentralized manner, i.e. a subcontroller is independently and locally equipped at each joint servoloop. To illustrate the performance of the controller, a numerical simulation example is provided. >
The Mechanism and Control of Fibrillation in the Mammalian Heart

The results of the present investigation are founded on a very extended study of the subject, carried on from time to time during the past 30 years, in the course of very numerous experiments (hundreds) on the mammalian heart. These results establish the conclusion that in fibrillation there is an essential change in the manner of conduction of the excitation process in the cardiac musculature; the relation of this change to the excitability of the muscle determines the appearance and characters of the different forms of “fibrillar” action that may be observed. The conduction of the excitation is essentially altered, inasmuch as it is propagated along the muscular fibre systems or fasciculi, instead of travelling directly through the muscular substance, without obvious regard to the arrangement of the fibres, as in the normal beat of the heart. Fascicular dissociation is an essential feature of fibrillation, which is, strictly speaking, a condition of “fasciculation” rather than “fibrillation. ” The essential change in conduction may be induced in very different ways. The state of fibrillation is rendered persistent by a disturbance in the normal relations of conduction time and refractory period in the cardiac musculature, resulting in the establishment of a mechanism of circulating excitations.
Width and Energy of Solar p-Modes Observed by Global Oscillation Network Group

We present measurements of mode width, Γ, and mean square velocity power, , derived from all currently processed 108 day Global Oscillation Network Group (GONG) time series and discuss their implications for p-mode excitation and damping. Assuming stochastic excitation, we estimate the energy per mode, E, and the energy supply rate, dE/dt. For modes with l = 9-150, the mean square velocity power and the mode energy peak at about 3.15 mHz reaching values of ≈ 1.4 × 103 cm2 s-2 and E ≈ 2.2 × 1028 ergs. The energy supply rate reaches a maximum value of dE/dt ≈ 2.5 × 1023 ergs s-1 near 3.6 mHz. The mode width shows the familiar "plateau" between 2.5 and 3.1 mHz with a "dip" near 2.9 mHz, which is strongest for l ≈ 40. This dip is most prominent during solar cycle minimum and disappears with increasing magnetic activity. The energy supply rate decreases on average by about 2.7% from the previous activity minimum to the currently highest level of activity. The solar cycle variation of dE/dt shows no frequency dependence, which is in marked contrast to the other mode parameters. The mode parameters are adequately represented by power laws in several frequency ranges, for example, dE/dt ~ ν6. 89±0.07 for 2.4 mHz ≤ ν < 3.0 mHz and dE/dt ~ ν-5.62±0.27 for 3.75 mHz ≤ ν < 4.5 mHz. The solar cycle variation of these parameters can then be expressed as changes of a few percent in the power-law exponents and multipliers. Our results agree reasonably well with previous studies of Birmingham Solar-Oscillations Network and Big Bear Solar Observatory data.
The evolution of QSOs derived from soft X-ray surveys

We present a study of the evolution of active galactic nuclei (AGN) selected in Einstein and ROSAT surveys. A total of 748 broad-line AGN are included in the study, including 29 with z > 2.Pure luminosity evolution provides a good description of the evolution for q(0) = 0. For q(0) = 0.5 we find that pure luminosity evolution underpredicts the number of intermediate-redshift (1.4 1.8) are rejected at high confidence levels. Models with no evolution or negative evolution at z >, 1.8 are acceptable. [V-e/V-a] tests, which are model-independent, suggest that at z > 1.8 evolution is negative, i.e., QSO space densities and/or luminosities decline with redshift. Our model luminosity functions predict that broad-line AGN with z < 4 contribute less than 45 per cent of the 1-2 keV X-ray background.We derive a simple expression to correct a two-power-law luminosity function for the spurious evolution caused by the dispersion of X-ray spectral slopes. When the dispersion in AGN spectral slopes is taken into account, we find that the redshift at which evolution stops may be as low as z similar to 1.4 for both q(0) = 0 and q(0) = 0.5.
NEWLY IDENTIFIED EXTENDED GREEN OBJECTS (EGOs) FROM THE SPITZER GLIMPSE II SURVEY. I. CATALOG

We have produced a catalog containing 98 newly identified massive young stellar object (MYSO) candidates associated with ongoing outflows (known as extended green objects, or EGOs). These have been identified from the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) II data set and our new identifications increase the number of known EGOs to ∼400 in our Galaxy, adding to the ∼300 previously identified EGOs reported by Cyganowski et al. from the GLIMPSE I survey. The high detection rate (∼70%) of 95 GHz class I methanol masers achieved in a survey toward 57 of these new EGOs with the Mopra 22 m radio telescope demonstrates that the new EGOs are associated with outflows. Investigations of the mid-infrared properties and physical associations with other star formation tracers (e.g., infrared dark clouds, class I and II methanol masers, and millimeter Bolocam Galactic Plane Survey sources) reveal that the newly identified EGOs are very similar in nature to those in the sample of Cyganowski et al. All of the observational evidence supports the hypothesis that EGOs correspond to MYSOs at the earliest evolutionary stage, with ongoing outflow activity, and active rapid accretion.
Admissible Majorants for Model Subspaces of H 2, Part I: Slow Winding of the Generating Inner Function

Abstract A model subspace ${{K}_{\Theta }}$ of the Hardy space ${{H}^{2}}={{H}^{2}}\left( {{\mathbb{C}}_{+}} \right)$ for the upper half plane ${{\mathbb{C}}_{+}}$ is ${{H}^{2}}\left( {{\mathbb{C}}_{+}} \right)\ominus \Theta {{H}^{2}}\left( {{\mathbb{C}}_{+}} \right)$ where $\Theta $ is an inner function in ${{\mathbb{C}}_{+}}$ . A function $\omega :\,\mathbb{R}\mapsto [0,\,\infty )$ is called an admissible majorant for ${{K}_{\Theta }}$ if there exists an $f\,\in \,{{K}_{\Theta }},\,f\,\not{\equiv }\,0,\,|f\left( x \right)|\,\le \,\omega \left( x \right)$ almost everywhere on $\mathbb{R}$ . For some (mainly meromorphic) $\Theta $ 's some parts of Adm $\Theta $ (the set of all admissible majorants for ${{K}_{\Theta }}$ ) are explicitly described. These descriptions depend on the rate of growth of arg $\Theta $ along $\mathbb{R}$ . This paper is about slowly growing arguments (slower than $x$ ). Our results exhibit the dependence of Adm $B$ on the geometry of the zeros of the Blaschke product $B$ . A complete description of Adm $B$ is obtained for $B$ 's with purely imaginary (“vertical”) zeros. We show that in this case a unique minimal admissible majorant exists.
Physical investigations and developments of Hall plasma thrusters

Ten years of R&D on Hall plasma thrusters (HPTs) in former USSR led to successful tests in space as early as 1972. Nevertheless, they remain actively investigated within the perspective of a routine use in space technologies. This long story underlines the contrast between a rather simple concept and a complex physical background, up to now not fully understood in a quantitative way. This lack of knowledge limits the development of fully predictive simulation codes. Industrial developments are, nevertheless, under way, with new goals in terms of thruster performances. Illustrations of such developments are given, but this paper is mainly focused on a review of recent results and open questions underlined through a coordinated research programme.
Microstructure and deformation micromechanisms of concentrated fiber bundle suspensions: An analysis combining x-ray microtomography and pull-out tests

The non-Newtonian rheology of concentrated fiber suspensions, such as short fiber reinforced polymer composites during their processing, depends on both the microstructure of their fibrous network and the deformation micromechanisms arising at fiber–fiber contacts. In this work, these two aspects are investigated using model concentrated fiber suspensions made up of short glass fiber bundles impregnated in a transparent polymer. For that purpose, multiresolution x-ray microtomography was used to analyze the fibrous microstructures, showing that the studied suspensions exhibit a planar fiber orientation with fairly straight fiber bundles, the connectivity of which can be modeled by the geometrical statistical tube model. Besides, bundle–bundle contact forces together with the interaction between the bundles and the suspending fluid are analyzed by using pull-out experiments. These tests allow the influence of the pull-out velocity, the confining stress and the volume fraction of fiber bundles on the pull-o.
A Factor Model for the Estimation of Multivariate Empirical Ground-Motion Models

A Bayesian latent factor to estimate multivariate empirical ground-motion models is proposed. In the factor model, event terms, site terms, and within-event/within-site residuals for each response oscillator period are modeled as linear combinations of a small number of latent factors, thus introducing inter-period correlation in the model. The factor model provides a lower-dimensional approximation to the full residual correlation structure. The factor model is demonstrated on Italian ground-motion data. Results indicate that the factor model leads to similar behavior as a traditional ground-motion model where each target is estimated separately
SPATIAL DISTRIBUTION OF STARS AROUND SIX METAL-POOR GLOBULAR CLUSTERS IN THE GALACTIC BULGE

Wide-field JHKs images obtained with the SIRIUS near-infrared camera of the IRSF 1.4m telescope are used to examine the tidal structures of the spatial stellar configuration around six metal-poor([Fe/H]< -1.0) globular clusters located within 3 kpc from the Galactic center. The radial surface density profiles are obtained from the surface photometry of the cluster images and the star counting for the photometric data. For the star counting, candidates of cluster member stars are selected with an filtering algorithm in color-magnitude diagrams. We find that the six target clusters show tidal overdensity features in the radial surface density profiles. There is a break inside the tidal radius for each cluster, and the profile in the outer overdensity region is characterized by a power law. Two- dimensional density maps of all the clusters show distorted asymmetric stellar configurations in the outer region. In five out of the six target clusters, the overdensity features are likely to be associated with the effects of the Galaxy dynamical interaction and the cluster space motions. The observed tidal configurations of stars suggest that several metal-poor clusters in the Galactic bulge are possibly surviving remnants of mergers to build the old stellar system of the Galactic bulge.
Measurement-scheduled control for the RTAC problem

The RTAC (rotational/translational actuator) nonlinear control design benchmark problem is addressed using a multiobjective control methodology based on linear matrix inequalities and robust control. The approach hinges on the search for quadratic Lyapunov functions ensuring various specifications (stability, L/sub 2/-gain, command input and output peak bounds) to hold for the closed-loop system. The resulting output-feedback controller is measurement-scheduled, its state-space matrices depend on the measurement vector in a nonlinear fashion. We evaluate the performance of our design with various simulations and predicted trade-off curves.
Progress towards a high-performing a-Si:H-based electro-optic modulator

Hydrogenated amorphous silicon (a-Si:H) has recently emerged as a promising material to provide microchips with passive and active photonic functions through a back-end and CMOS-compatible technological process. In this paper, we discuss the performance achieved with different configurations of a-Si:H-based electro-optical amplitude modulators integrated into passive waveguides. All of the analysed devices are based on the plasma dispersion effect, a phenomenon that allows us to reach useful performance at the communication wavelength of λ ∼ 1.55 μm. The behaviour of the various proposed modulation approaches has been tested by ad hoc interferometric structures, such as Fabry–Perot integrated resonators or integrated Mach–Zehnder interferometer, as well as by multistack devices to enhance the static modulation efficiency. The performance of each modulator has been analysed through several figures of merit.
Numerical investigations of shear localization in a micro‐polar hypoplastic material

In this paper a micro‐polar continuum approach is proposed to model the essential properties of cohesionless granular materials like sand. The model takes into account the influence of particle rotations, the mean grain size, the void ratio, the stresses and couple stresses. The constitutive equations for the stresses and couple stresses are incrementally non‐linear and based on the concept of hypoplasticity. For plane strain problems the implementation of the model in a finite element program is described. Numerical studies of the evolution of micro‐polar effects within a granular strip under plane shearing are presented. It is shown that the location and evolution of shear localization is strongly influenced by the initial state and the micro‐polar boundary conditions. For large shearing the state quantities tend towards a stationary state for which a certain coupling between the norm of the stress deviator and the norm of the couple stress tensor can be derived. Copyright © 2003 John Wiley & Sons, Ltd.
ELASTIC MODULI OF A SINGLE QUASICRYSTAL OF DECAGONAL AL-NI-CO : EVIDENCE FOR TRANSVERSE ELASTIC ISOTROPY

The single quasicrystal elastic moduli c{sub ij} of decagonal Al-Ni-Co were determined using resonant ultrasound spectroscopy at selected fixed temperatures in the range between 5 and 290K. Decagonal Al-Ni-Co is found to be transversely elastically isotropic to (0.02{plus_minus}0.04){percent} . The elastic moduli c{sub ij}(T) exhibit weak temperature dependences. The elastic Debye temperature {Theta}{sup el}{sub D} calculated from c{sub ij} measured at 5K agrees well with the thermodynamic Debye temperature {Theta}{sup th}{sub D} obtained from a low-temperature specific-heat experiment. {copyright} {ital 1998} {ital The American Physical Society}
VLA Imaging of Class I Methanol Masers at 7 Millimeters with Angular Resolution ~0.″2

Eight class I methanol masers [DR21(OH), DR21W, OMC-2, NGC 2264, M8E, NGC 6334I(N), L379, W33Met] in the transition 70-61A+ at 44069 MHz were imaged with angular resolution ~0. ″2 with the VLA. The images show a different distribution of maser "spots" from a simple structure of one or two spots at NGC 2264, M8E, DR21W, to a very complex structure of many spots at DR21(OH) (17 spots), OMC-2 (8 spots), NGC 6364I(N) (23 spots), L379 (11 spots), and W33Met (5 spots). Some spots are partially resolved, but the majority of them are still unresolved. The maximum brightness temperatures of the methanol (44,069 MHz) emission features at the observed sources ranges from 1.9 × 106 to 3.6 × 108 K. The velocity range varies from the minimum 0.8 km s-1 at NGC 2264 to the maximum 6.9 km s-1 at DR21(OH).
The 12/13 January 1988 Narrow Cold-Frontal Rainband Observed during MFDP/FRONTS 87. Part I: Kinematics and Thermodynamics

Abstract The kinematic and thermodynamic structure of a narrow cold-frontal rainband (NCFR) observed during the English–French–German MFDP/FRONTS 87 experiment is presented. Radiosonde data indicated a very weak convective instability below 1500-m altitude and a low-level jet of 30 m s−1 from SSW before the arrival of the front; a cooling of about 1°C associated with an airflow of 13 m s−1 from WSW after its passage. A composite of wind and reflectivity fields from 17 dual-Doppler radar analyses shows high reflectivity values, large convergence, and relatively intense vertical motions associated with this NCFR at the 1000-m altitude. A mean vertical cross section perpendicular to the surface front, derived from three successive high-resolution dual-Doppler scans, is used to examine the general characteristics of the air circulation. A structure apparently similar to that of a density current is observed. Above the 2-km altitude, however, air flowing at a speed faster than the surface front appreciably mod.
Chemometric approach to chromatic spatial variance. Case study: patchiness of the Skyros wall lizard

In this paper, we demonstrate how to take advantage of the large number of spatial samples provided by commercial multispectral RGB imagers. We investigate the possibility to use various multidimensional histograms and probability distributions for decomposition and predictive models. We show how these methods can be used in an example using images of different Skyros wall lizards and demonstrate improved performance in prediction of color morph compared with traditional parameterization techniques of spatial variance. Copyright © 2012 John Wiley & Sons, Ltd.
Two-surface-plasmon-polariton-absorption based lithography using 400 nm femtosecond laser

The two-surface-plasmon-polariton-absorption (TSPPA) at the vacuum wavelength of 400 nm is observed, and the subwavelength lithography, by using this nonlinear phenomenon, is demonstrated. Resist patterns with the period of ∼138 nm have been obtained by exciting the SPP at the Al/resist interface with the 400 nm femtosecond laser. By altering the exposure time, the exposure linewidth reduces from ∼90 nm to ∼55 nm, which explores the ability of the TSPPA based lithography at the short wavelength. The factors limiting the performance of the proposed TSPPA based lithography are discussed in detail.
Non-contact detection of cardiac rate based on visible light imaging device

We have developed a non-contact method to detect human cardiac rate at a distance. This detection is based on the general lighting condition. Using the video signal of human face region captured by webcam, we acquire the cardiac rate based on the PhotoPlethysmoGraphy theory. In this paper, the cardiac rate detecting method is mainly in view of the blood’s different absorptivities of the lights various wavelengths. Firstly, we discompose the video signal into RGB three color signal channels and choose the face region as region of interest to take average gray value. Then, we draw three gray-mean curves on each color channel with time as variable. When the imaging device has good fidelity of color, the green channel signal shows the PhotoPlethysmoGraphy information most clearly. But the red and blue channel signals can provide more other physiological information on the account of their light absorptive characteristics of blood. We divide red channel signal by green channel signal to acquire the pulse wave. With the passband from 0.67Hz to 3Hz as a filter of the pulse wave signal and the frequency spectrum superimposed algorithm, we design frequency extracted algorithm to achieve the cardiac rate. Finally, we experiment with 30 volunteers, containing different genders and different ages. The results of the experiments are all relatively agreeable. The difference is about 2bmp. Through the experiment, we deduce that the PhotoPlethysmoGraphy theory based on visible light can also be used to detect other physiological information.
Energetics of grid turbulence in a stably stratified fluid

A biplane grid with a mesh spacing of 10.8 cm was towed horizontally in a towing tank to generate turbulence in a non-stratified fluid and in stratified fluids with different constant density gradients. Turbulence velocity components and density fluctuations were measured using an array of cross-film and conductivity probes. Based on the mesh size of the grid, the nominal values of the (internal) Froude numbers were ∞, 80 and 40, and the corresponding Reynolds number was 4.3 × 104. The decay rates of the (turbulence) kinetic, potential and total energies and the dissipation rates of the kinetic and potential energies were calculated from the experimental data. For each of these quantities, the decay may be represented as a function of the downstream distance raised to a given power. The kinetic energy and its dissipation rate are lower for the stratified cases than for the non-stratified case but are almost compensated for by the corresponding potential energy and its dissipation rate. Our results are consistent with those of direct numerical simulations and agree reasonably well with those obtained in stratified wind and water tunnels. However, the results differ from laboratory results obtained using an optical method to measure the turbulent motion of tracer particles in the wake of a vertically towed grid; these latter results show an abrupt reduction in the decay rate of the turbulence kinetic energy after one Brunt–Väisälä period. A similar trend is also observed in results obtained in facilities with fairly high background turbulence or internal waves. This discrepancy is discussed and an explanation is presented. Furthermore, it is demonstrated that strongly stratified thin sheets with density gradients larger than that of the undisturbed fluid may be generated by local but incomplete mixing. The persistence of such thin sheets is proportional to the Schmidt number (≈ 500) in stratified salt water or the Prandtl number (≈ 0.71) in thermally stratified air.
THE THAYER METHOD OF INSTRUCTION AT THE UNITED STATES MILITARY ACADEMY: A MODEST HISTORY AND A MODERN PERSONAL ACCOUNT

ABSTRACT In 2002, The United States Military Academy at West Point celebrates its bicentennial. For most of those two hundred years the academy has taught its courses by what is known as the Thayer method of instruction. In short, the philosophy is that cadets are responsible for their own learning. They study the material prior to attending class. The learning is then reinforced in class through a combination of group learning and active learning exercises done primarily at the blackboards. I will give a short overview of how instruction at West Point has evolved in two hundred years, along with a discussion of our current teaching methods and how they can be integrated into any science classroom.
Tikhonov regularization of nonlinear III-posed problems in hilbert scales

In this paper we consider nonlinear ill-posed problems F(x) = y 0, where x and y 0 are elements of Hilbert spaces X and Y, respectively. We solve these problems by Tikhonov regularization in a Hilbert scale. This means that the regularizing norm is stronger than the norm in X. Smoothness conditions are given that guarantee convergence rates with respect to the data noise in the original norm in X. We also propose a variant of Tikhonov regularization that yields these rates without needing the knowledge of the smoothness conditions. In this variant F is allowed to be known only approximately and X can be approximated by a finite-dimensional subspace. Finally, we illustrate the required conditions for a simple parameter estimation problem for regularization in Sobolev spaces.