Miracle-dz/UniFAR-FTUs huggingface dataset:
Herschel far-IR observations of the Chamaeleon molecular cloud complex ! Chamaeleon I: A first view of young stellar objects in the cloud

Context. The Herschel Gould Belt survey of nearby star forming regions is providing great insights into the early stages of the formation and the evolution of stars and their circumstellar disks. The Chamaeleon I dark cloud is an elongated region of dense dust and gas where star formation is ongoing in two centres, a northern region centred on Ced 112 and a southern cluster subdivided into the two regions Ced 110 and 111. Aims. In this initial study we present Herschel data of previously identified young stellar objects (YSOs) in the cluster, focusing on the spatial distribution of the YSOs and the determination of the relative colours of the protostars and the disk-bearing stars in Chamaeleon I. Methods. Chamaeleon I has been observed as part of the Herschel Gould Belt Survey, using the PACS and SPIRE parallel mode imaging at 70, 160, 250, 350, and 500 μm. Source extraction was performed using the getsources software. Results. We have detected 397 sources over the five available PACS and SPIRE bands, and through comparison with previously identified objects in the cluster we have identified 49 YSOs, 4 bright nebular emission features, five CO clumps, and twenty-eight candidate prestellar or starless cores in the Herschel sample. The remaining sample consists of candidate prestellar cores, condensations within the cloud, or background galaxies. The Herschel detected YSOs are highly clustered and mainly associated with the three known Cederblad groups. The observations clearly show that the young stars are forming coincident with the denser regions of cold dust and gas, visible at longer Herschel wavelengths. Those YSOs detected with Herschel were found to have an IRAC m3.6 μm < 10. No difference was found in the Herschel colours between the class I and class II young stars, however the class I sources were brighter than the class II at most Herschel wavelengths. One class III star and three transition disks are detected.
The Descendants of Lyman Break Galaxies in Galaxy Clusters: Spatial Distribution and Orbital Properties

We combine semianalytical methods with an ultra-high-resolution simulation of a cluster (of mass 2.3 × 1014 h-1 M☉ and 4 × 106 particles within its virial radius) formed in a standard cold dark matter universe to study the spatial distribution and orbital properties of the present-day descendents of Lyman break galaxies (LBGs). At redshift 3 we find on average a total of 12 halos containing at least one LBG in the region that will later collapse to form the cluster itself. At the present time only five of these halos survive as separate entities inside the cluster virial radius, having been stripped of most of their dark matter. Their circular velocities are in the range 200-550 km s-1. Seven halos merged together to form the central object at the very center of the cluster. Using semianalytical modeling of galaxy evolution we show that descendents of halos containing the most massive LBGs now host giant elliptical galaxies such as those typically found in rich galaxy clusters. Inside the simulated cluster, galaxy orbits are very radial, with a pericenter-to-apocenter ratio of about 1 : 5. The orbital eccentricities of LBG descendents are statistically indistinguishable from those of the average galaxy population inside the cluster, suggesting that the orbits of these galaxies are not significantly affected by dynamical friction decay after the formation of the cluster's main body. In this cluster, possibly because of its early formation time, the descendents of massive LBGs are contained within the central 60% of the cluster virial radius and have an orbital velocity dispersion lower than the global galaxy population, originating a mild luminosity segregation for the brightest cluster members. Mass estimates based only on massive LBG descendents (especially including the central cD) reflect this bias in space and velocity and underestimate the total mass of this well-virialized cluster by up to a factor of 2 compared to estimates using at least 20 cluster members.
Young's Orthogonal Form for Brauer's Centralizer Algebra

Moreover, for the classical group G any irreducible representation of Ž . C n, N appears at most once in the restriction of an irreducible repreŽ . sentation of C n q 1, N . Therefore a canonical basis exists in any irreŽ . ducible representation V of C n, N . Its vectors are the eigenvectors for Ž . Ž . the subalgebra X n, N in C n, N generated by all the central elements in the members of the above chain. Ž . Ž . For the group G s GL N, C the centralizer C n, N is generated by Ž . mn the permutational action of the symmetric group S n in U . The action Ž . of S n on the vectors of the canonical basis in V was described for the w x w x first time by A. Young Y . G. Murphy Mp rederived the formulas from w x Ž . Y by using the properties of the subalgebra X n, N . Ž . Let us now suppose that G is the orthogonal group O N, C . To Ž . describe the corresponding centralizer algebra C n, N explicitly, R. Brauer w x Ž . Br introduced a certain complex associative algebra B n, N along with a Ž . homomorphism onto C n, N . This homomorphism is injective if and only
Idempotent rank in finite full transformation semigroups

Synopsis The subsemigroup Singn of singular elements of the full transformation semigroup on a finite set is generated by n(n − l)/2 idempotents of defect one. In this paper we extend this result to the subsemigroup K(n, r) consisting of all elements of rank r or less. We prove that the idempotent rank, defined as the cardinality of a minimal generating set of idempotents, of K(n, r) is S(n, r), the Stirling number of the second kind.
Radar target identification using a combined early-time/late-time E-pulse technique

The E-pulse technique has been applied in the past to both the early- and the late-time components of a transient radar response. While the late-time E-pulse technique uses aspect-independent waveforms, the early-time E-pulse technique requires a separate waveform for each target aspect angle and thus significantly more storage and processing time. This paper discusses a combination of the two techniques that employs the early-time technique to remove ambiguities generated from application of the late-time method. By narrowing the possible range of aspect angles of the potential targets, the early-time technique can be employed more efficiently.
Modulation Instability of Ion-Acoustic Waves in Plasma with Nonthermal Electrons

Modulational instability of ion-acoustic waves has been theoretically investigated in an unmagnetized collisionless plasma with nonthermal electrons, Boltzmann positrons, and warm positive ions. To describe the nonlinear evolution of the wave amplitude a nonlinear Schrodinger (NLS) equation has been derived by using multiple scale perturbation technique. The nonthermal parameter, positron concentration, and ion temperature are shown to play significant role in the modulational instability of ion-acoustic waves and the formation of envelope solitons.
Backward traveling rotating stall waves in centrifugal compressors

Rotating stall waves that travel against the direction of rotor rotation are reported for the first time and a new, low-order analytical approach to model centrifugal compressor stability is introduced. The model is capable of dealing with unsteady radially swirling flows and the dynamic effects of impeller-diffuser component interaction as it occurs in centrifugal compression systems. A simple coupling criterion is developed from first principles to explain the interaction mechanism important for system stability. The model findings together with experimental data explain the mechanism for first-ever observed backward traveling rotating stall in centrifugal compressors with vaned diffusers. Based on the low-order model predictions, an air injection scheme between the impeller and the vaned diffuser is designed for the NASA Glenn CC3 high-speed centrifugal compressor The steady air injection experiments show an increase of 25% in surge-margin with an injection mass flow of 0.5% of the compressor mass flow. In addition, it is experimentally demonstrated that this injection scheme is robust to impeller tip-clearance effects and that a reduced number of injectors can be applied for similar gains in surge-margin. The results presented in this paper firmly establish the connection between the experimentally observed dynamic phenomena in the NASA CC3 centrifugal compressor and a first principles based coupling criterion. In addition, guidelines are given for the design of centrifugal compressors with enhanced stability.
A correction note on A family of optimal iterative methods with fifth and tenth order convergence for solving nonlinear equations

In M. Matinfar, M. Aminzadeh (2012) [M. Matinfar, M. Aminzadeh, A family of optimal iterative methods with fifth and tenth order convergence for solving nonlinear equations, J. of Interpolation and Approximation in Scientific Computing, volume 2012, year 2012, article id jiasc-00012, 11 pages, doi:10.5899/2012/jiasc-00012. ], an iterative method with fifth and tenth order of convergence has been proposed. In this note, we show that the both proofs of proposed iterative schemes are incorrect. The both iterative schemes are quadratically convergent.
Diffuse photon probes of structural and dynamical properties of turbid media: Theory and biomedical applications

DIFFUSE PHOTON PROBES OF STRUCTURAL AND DYNAMICAL PROPERTIES OF TURBID MEDIA THEORY AND BIOMEDICAL APPLICATIONS David A Boas Arjun G Yodh Di using photons can be used to detect localize and characterize optical and dynamical spatial inhomogeneities embedded in turbid media Measurements of the intensity of di use photons reveal information about the optical properties of a system Speckle uctuations carry information about the dynamical and optical properties This dissertation shows that simple di usion theories accurately model the intensity and speckle correlation signals that di use through turbid media with spatially varying properties and discusses possible biomedical applications We rst look at the intensity of di use photons provided by a light source that is intensity modulated This generates di use photon density waves DPDW s which exhibit classical wave behavior We demonstrate experimentally and theoretically the refraction di raction and scattering of DPDW s Using accurate signal and noise models we then present a detailed analysis which shows that DPDW s can be used to detect and locate objects larger than mm and to characterize objects larger than cm which are embedded inside turbid media with biologically relevant parameters This di use photon probe should may nd applications in medicine as a bed side brain hematoma monitor or for screening breast cancer or other functional imaging applications We then consider the coherence properties of the di use photons as revealed by speckle intensity uctuations and show that the temporal autocorrelation function of these uctuations is accurately modeled by a correlation di usion equation Because the correlation di usion equation is analogous to the photon di usion equation all concepts and ideas developed for DPDW s can be directly applied to the di usion of correlation We show experimentally and with Monte Carlo simulations that the dif
Local-field effects in nanostructured photonic materials

It is well known that the optical response of a medium depends on the local field acting on an individual emitter rather than on the macroscopic average field in the medium. The local field depends very sensitively on the microcopic environment in an optical medium. It is thus possible to achieve a significant control over the local field by intermixing homogeneous materials on a nanoscale to produce composite optical materials. A combination of local-field effects and nanostructuring provides new degrees of freedom for manipulating the optical properties of photonic materials. Especially interesting opportunities open up in the nonlinear optical regime where the material response depends on the local-field correction as a power law. The goal of this review is to present a conceptual overview of the influence of local-field effects on the optical properties of photonic materials, both homogeneous and composite. We also give a summary of recent achievements in controlling the optical properties by local-field effects and nanostructuring.
An exact algorithm for a workforce allocation problem with application to an analysis of cross-training policies

The evaluation of workforce staffing and scheduling policies is of paramount importance for meeting the challenge of simultaneously providing good customer service and low operational costs. Policy studies are particularly critical in workforce environments plagued by staffing shortages. The cross-utilization of employees among different departments or work centers is a well-recognized staffing policy for coping with shortages. We revisit a non-linear assignment problem for allocating cross-trained workers so as to maximize overall utility, which is measured using a quadratic function of labor shortages. We develop a branch-and-bound algorithm that efficiently provides optimal solutions for problems of practical size. This algorithm is then used to conduct a computational investigation of cross-training policies. Among the most critical factors affecting utility improvement are the coefficient of variation for demand, worker absenteeism, the percentage of cross-trained workers and cross-training breadth. Several important interactions among these and other factors are also identified.
Bifurcation générique d’ondes rotatives d’isotropie maximale

Abstract – I. Melbourne [9] has recently announced an existence theorem for generic bifurcationof rotating waves with maximal isotropy for vector ﬁelds which are equivariant under an absolutelyirreducible action of a compact Lie group. Melbourne’s proof relies on recent results of Field [4, 5]. Rotating waves can also be interpreted as equilibria on the orbit space of the group action, and thepurpose of this note is to present a proof using geometric arguments directly on this orbit space,arguments similar to those of [7]. Abridged English Version Let G be a compact Lie group acting absolutely irreduciblyon a ﬁnite dimensional vector space V. We consider a generic (see lemma 1 for the deﬁnition ofthesetH(V)ofgenericvectorﬁelds)G-equivariantsmoothvectorﬁeld ˙x = f(x,λ), f(0,0) = 0which has a non-degenerate stationary bifurcation at (0,0). I. Melbourne [9] has recently givenan existence theorem for branches of rotating waves (relative equilibria foliated by periodicsolutions) bifurcating from zero for two classes of maximal isotropy subgroups; he also givesexplicit examples of such bifurcations for each of those classes. Melbourne’s proof is basedon recent results of Field [4, 5]. Our proof of this existence result uses the projection of thevector ﬁeld on the orbit space V/G, as done in [7]. If we consider θ
Chaos and Chaos Control in Network Dynamical Systems

Even fully deterministic dynamics may be chaotic, i.e., essentially unpredictable as time evolves. The first part of this thesis concerns the emergence of chaos in dynamical systems with symmetry, in particular certain networks of phase oscillators which are used to model some oscillatory physical systems. Although the presence of symmetry places strong constraints on the dynamics, we show that chaotic dynamics can in fact appear in symmetric systems of phase oscillators. Moreover, we study the dynamical mechanisms that give rise to chaotic dynamics. Even though chaotic dynamics implies unpredictability, so-called chaos control exploits features of chaotic motion; its aim is the stabilization of unstable periodic orbits. The focus of the second part of this thesis is on Predictive Feedback Control as a chaos control method, in particular with respect to convergence speed. First, we show that optimal asymptotic convergence speed of Predictive Feedback Control may be improved through an adaptive algorithm. It turns out that Predictive Feedback Control is not suitable for stabilizing highly unstable periodic orbits. Thus, we consequently develop and study an extension of Predictive Feedback Control which is obtained by stalling the application of the control signal. We show that the new method improves performance with respect to asymptotic convergence speed while maintaining most of the advantages in implementation of Predictive Feedback Control. The speedup persists in the full nonlinear system as confirmed by numerical simulations with and without adaptation.
Jovian type III radio bursts

Radio bursts have been observed in the Voyager plasma wave data from Jupiter that bear a striking resemblance to solar type III radio bursts. The emissions lie in the frequency range near 10 kHz, have durations of a minute or so, and occur in a set of periodically spaced bursts. The spacing between primary bursts is typically 15 min, but the bursts may have additional components which recur on time scales of about 3 min. The similarity with solar type III radio bursts suggests a source mechanism involving the movement of energetic electrons through a density gradient in the plasma surrounding Jupiter. The periodicity of bursts suggests Io may be involved in the generation of waves, since the timing is similar to the Alfven wave travel time from one hemisphere to the other through the Io torus.
Nonlinear Follow-the-Leader Models of Traffic Flow

A variety of nonlinear follow-the-leader models of traffic flow are discussed in the light of available observational and experimental data. Emphasis is placed on steady-state flow equations. Some trends regarding the advantages of certain follow-the-leader functionals over others are established. However, it is found from extensive correlation studies that more data are needed before one can establish the unequivocal superiority of one particular model. A discussion is given of some ideas concerning the possible reasons for the existence of a bimodal flow versus concentration curve especially for multilane highways.
Microstructure and effective behavior of materials

Tailor‐made materials often take advantage of surprising material behavior which is related to special effects and structures on small length scales. In order to achieve the design goals, a precise understanding of the underlying mechanisms in a mathematical model is indispensable. This contribution presents modern methods in the calculus of variations which are available for the analysis and numerical simulation of systems with multiple scales and illustrates their use in two characteristic model examples.
Citizen Voting Power Under the Electoral College: A Stochastic Model Based on State Voting Patterns

An empirical measure of marginal citizen voting power in a Presidential election under the Electoral College system is developed which reflects the relative probability that citizens of different states affect the outcomes of Presidential elections over an historical period. The model employs normal probability densities whose parameters are determined by state voting patterns in a sample of Presidential elections.According to this measure, for the period 1900–1972, $50\% $ of the population of the United States had only $26\% $ of the total voting power, compared to $39\% $ for the Banzhaf index, which is based on population alone. The value of the measure of voting power developed in this paper is given for the citizens of each state. This value appears in general to increase with greater heterogeneity of the state voting population, regardless of population size. Finally, confidence intervals for the values are determined and empirical support is offered for the assumptions made in the model.
Analytical solution of a two-dimensional stagnation flow in the vicinity of a shrinking sheet by means of the homotopy analysis method

Abstract In this article, stagnation flow in the vicinity of a shrinking sheet is studied. A similarity transformation is employed to reduce the Navier—Stokes equations to a set of non-linear ordinary differential equations. These equations are then solved analytically by means of the homotopy analysis method (HAM). The results obtained were shown to compare well with the numerical results available in the literature for the same problem. Close agreement between the two sets of results indicates the accuracy of the HAM. The method can predict the flow field in all vertical distances from the sheet, and is also able to control the convergence of the solution. The numerical solution of the similarity equations is also developed and the results are in good agreement with the analytical results based on the HAM.
Self-pressed radiating theta discharge with trapped magnetic flux

Numerical simulation of a radiating theta discharge pressed to the inner wall of a cylindrical dielectric chamber under the pressure of a trapped longitudinal magnetic field has been carried out in a high-pressure gas. The longitudinal magnetic field is created by a solenoid, which acts as inductive energy storage; an electro-explosive current breaker is used as an opening switch for this energy storage. It is shown that discharges of this type allow radial converging radiation fluxes of different spectral structures to be formed and the luminance temperature on the axis to vary in the range of several electronvolts.
Thermal electron acceleration by electric field spikes in the outer radiation belt: Generation of field‐aligned pitch angle distributions

Van Allen Probes observations in the outer radiation belt have demonstrated an abundance of electrostatic electron‐acoustic double layers (DL). DLs are frequently accompanied by field‐aligned (bidirectional) pitch angle distributions (PAD) of electrons with energies from hundred eVs up to several keV. We perform numerical simulations of the DL interaction with thermal electrons making use of the test particle approach. DL parameters assumed in the simulations are adopted from observations. We show that DLs accelerate thermal electrons parallel to the magnetic field via the electrostatic Fermi mechanism, i.e., due to reflections from DL potential humps. The electron energy gain is larger for larger DL scalar potential amplitudes and higher propagation velocities. In addition to the Fermi mechanism, electrons can be trapped by DLs in their generation region and accelerated due to transport to higher latitudes. Both mechanisms result in formation of field‐aligned PADs for electrons with energies comparable to those found in observations. The Fermi mechanism provides field‐aligned PADs for <1 keV electrons, while the trapping mechanism extends field‐aligned PADs to higher‐energy electrons. It is shown that the Fermi mechanism can result in scattering into the loss cone of up to several tenths of percent of electrons with flux peaking at energies up to several hundred eVs.
Derivation of Formulations 1 and 1A of Farassat

Formulations 1 and 1A are the solutions of the Ffowcs Williams-Hawkings (FW-H) equation with surface sources only when the surface moves at subsonic speed. Both formulations have been successfully used for helicopter rotor and propeller noise prediction for many years although we now recommend using Formulation 1A for this purpose. Formulation 1 has an observer time derivative that is taken numerically, and thus, increasing execution time on a computer and reducing the accuracy of the results. After some discussion of the Green's function of the wave equation, we derive Formulation 1 which is the basis of deriving Formulation 1A. We will then show how to take this observer time derivative analytically to get Formulation 1A. We give here the most detailed derivation of these formulations. Once you see the whole derivation, you will ask yourself why you did not do it yourself!