Miracle-dz/UniFAR-FTUs huggingface dataset:
Reply to ''Comment on 'Lienard systems, limit cycles, and Melnikov theory' ''

The problem of finding the number of limit cycles of Lienard systems, ẋ5y2«F(x ,m), ẏ52x , where F(x ,m) is an odd polynomial, was addressed by Giacomini and Neukirch @Phys. Rev. E 56, 3809 ~1998! #, and they proposed an original method, where a sequence of polynomials is introduced, whose roots give the number of limit cycles that also allow one to construct a sequence of algebraic approximations to the limit cycles. This author showed @Phys. Rev. E 57, 340 ~1998! # that in the limit of these sequences, the same information is given by a polynomial which Melnikov theory associates to each Lienard system. In their comment, Giacomini and Neukirch @Phys. Rev. E 59, 2483 ~1999! # remark that this is correct only for small values of « . I wish to stress here that this is right and that the reason for it lies in the perturbative nature of Melnikov theory, while the Giacomini and Neukirch method is nonperturbative. As a consequence the original conjecture is reformulated. @S1063-651X~98! 12612-0#
Perceptual and prosodic factors in cluster timing: Manner, order, and syllable position effects in Polish consonant clusters

We investigate timing in Polish tautosyllabic C1C2 clusters differing in manner, consonant order, and syllable position. Hoole et al. (2013) reported for German that perceptual constraints may condition timing differences in /kn/ and /kl/ clusters due to the nasal but not the lateral obscuring the preceding stop burst. Using articulography, we test this hypothesis for a variety of Polish onset clusters (C1={m, p, k}, C2={n, l, r}). Results from three speakers confirm a significant influence of both C1 and C2 on timing patterns. A C1 nasal shows more overlap than a stop. For C2, /l/ shows more overlap than /n/, consistent with the German results. However, the relative difference between C2=/n/ and C2=/l/ holds independently of whether C1 is a nasal or a stop, contra the perception hypothesis. Further, it is known from several languages that onset clusters overlap less than coda clusters, yet this observation has been confounded by the sonority conditioned change in consonant order in onset/coda. Polish has.
The Distribution of HCO+ J = 4-3 and HCN J = 4-3 in the Nuclear Region of M82

We present the first detection of HCN J = 4-3 in the starburst galaxy M82 and a fully sampled grid of the distribution of its emission in the nuclear region. The angular resolution is 14'' and the velocity resolution 6.3 km s-1. The distribution of HCN emission is compared with that of HCO+ J = 4-3 made with the same resolution, and the conclusion is that the HCO+/HCN brightness ratio is higher at J = 4-3 than at lower transitions, with a median ratio of 3.5. There is evidence for a variation in this ratio across the nuclear region, with higher values toward the edge of the nuclear disk. This variation is consistent with a variation in gas density, with higher densities associated with regions closer to the nucleus of M82. However, some of this variation could also be produced by a variation in the HCO+/HCN abundance ratio. A large-scale velocity gradient (LVG) analysis of three transitions in each molecule centered at the nucleus shows that the line ratios within each species and between the two species are consistent with a common set of physical conditions for the emitting regions, namely, a kinetic temperature of 50 K, gas density 105 cm-3, and gas column density 1022 cm-2. Although it has been suggested that HCO+ may be subject to mechanisms of excitation other than collisions with H2, such as electron collisions, our analysis shows that there is no reason to invoke any such mechanisms to account for the line ratios present. The HCO+/HCN intensity ratio is known to vary significantly from one galaxy to another, with M82 at the high end of the spectrum of variation. This effect is briefly discussed in the context of a bistable chemical equilibrium model in which the HCO+ abundance is a sensitive function of the cosmic-ray ionization rate and gas density in the cloud cores. Within the framework of this picture, a high cosmic-ray flux could be inversely related to HCO+ abundance, contrary to what is generally assumed.
Topological Quantum Computation

The theory of quantum computation can be constructed from the abstract study of anyonic systems. In mathematical terms, these are unitary topological modular functors. They underlie the Jones poly- nomial and arise in Witten-Chern-Simons theory. The braiding and fusion of anyonic excitations in quantum Hall electron liquids and 2D-magnets are modeled by modular functors, opening a new possi- bility for the realization of quantum computers. The chief advantage of anyonic computation would be physical error correction: An error rate scaling like e −αl , where l is a length scale, and α is some posi- tive constant. In contrast, the "presumptive" qubit-model of quantum computation, which repairs errors combinatorically, requires a fantas- tically low initial error rate (about 10 −4 ) before computation can be stabilized. Quantum computation is a catch-all for several models of computation based on a theoretical ability to manufacture, manipulate and measure quan- tum states. In this context, there are three areas where remarkable algo- rithms have been found: searching a data base (15), abelian groups (factor- ing and discrete logarithm) (19 ,27), and simulating physical systems (5 ,21). To this list we may add a fourth class of algorithms which yield approximate,
The Algol-like binary TT Hydrae - The stars, circumstellar matter, and superionized plasma

This paper reports on superionized UV emission lines discovered in TT Hydrae (HD 97528), a semidetached eclipsing binary system in the Southern-Hemisphere sky. The list of emission lines observed is typical for interacting nondegenerate binaries of the Algol type, but with system-specific relative-intensity characteristics. The primary component of the system is a B9.5 V main-sequence star with effective temperature of 9800 K. Its mass equals 2.25 solar masses; the radius is 1.9 solar radii; and surface gravity log g equals 4.23. The secondary star has a mass of 0.41 solar mass and fills its critical Roche lobe. Evidence obtained on mass interaction supports the conclusion that HD 97528 is a normal semidetached system. 40 references.
Large eddy simulation of the effects of mild swirl on the near field of a round free jet

The near fields of turbulent round free jets with swirl numbers of S=0.0 and 0.24 are modeled with large eddy simulations that use a dynamic Smagorinsky subgrid scale model. The time-averaged results are in accordance with other numerical and experimental data. Instantaneous plots of vorticity are used to examine the evolution of and interaction between coherent structures. Ring structures aligned with the plane normal to the flow form downstream of the jet shear layer and collide with the streamwise braid structures. The resulting interaction cause the rings to break apart into smaller, less organized turbulence structures. The addition of swirl increases the number of streamwise braids, which enhances the breakdown mechanism of the rings. The results suggest that the increased entrainment observed in swirling flows is due to the action of the braids rather than the rings.
Structurally stable Grassmann transformations

A Grassmann transformation is a diffeomorphism on a Grassmann manifold which is induced by an n x n nonsingular matrix. In this paper the structurally stable Grassmann transformations are characterized to be the maps which are induced by matrices whose eigenvalues have distinct moduli. There is exactly one topological conjugacy class of complex structurally stable Grassmann transformations. For the real case the topological classification is determined by the ordering (relative to modulus) of the signs of the eigenvalues of the inducing matrix.
Spatially Resolved Spectroscopy of the Chandra Field Containing the Supernova Remnant G292.2–0.5

We present observations with the Chandra Advanced CCD Imaging Spectrometer (ACIS-S) of the western interior of the supernova remnant (SNR) G292.2-0.5 associated with the high magnetic field pulsar (PSR) J1119-6127. Chandra's excellent resolution revealed 18 point sources on the S3 chip and allowed the study of the diffuse emission from G292.2-0.5 independently from these point sources. The diffuse emission from G292.2-0.5 can be adequately fitted with nonequilibrium ionization models; however, these fits result in an unrealistically high temperature (kT > 3 keV), indicating the presence of a hard nonthermal component. By performing a spatially resolved spectroscopic study of the remnant, we identify the nonthermal emission as originating from the region closer to the pulsar. Its spectrum is well described with a power law with a photon index of Γ ~ 1-2. As a result of the flat spectrum and location close to the pulsar, we propose that this nonthermal emission arises from the injection of high-energy particles originating from PSR J1119-6127 and its pulsar wind nebula (PWN) into the SNR shell. As for the 18 point sources revealed by Chandra, only 3 sources have previously known counterparts at other wavelengths. Two of these sources exhibit enough counts to extract a spectrum, one being a new source CXOU J111911.8-613026 and the other being the X-ray counterpart of PSR J1119-6127 studied by us in a previous work. The spectrum of the new source CXOU J111911.8-613026 is soft (power-law photon index Γ ~ 3.6-4.6 or blackbody temperature kT ~ 0.2-0.36 keV) with a luminosity comparable to that of faint radio-quiet neutron stars. The nature of CXOU J111911.8-613026, however, cannot be determined with the present data and has to await further observations.
The IOS Test for Model Misspecification

A new test of model misspecification is proposed, based on the ratio of in-sample and out-of-sample likelihoods. The test is broadly applicable and, in simple problems, approximates well-known, intuitive methods. Using jackknife influence curve approximations, it is shown that the test statistic can be viewed asymptotically as a multiplicative contrast between two estimates of the information matrix, both of which are consistent under correct model specification. This approximation is used to show that the statistic is asymptotically normally distributed, although it is suggested that p values be computed using the parametric bootstrap. The resulting methodology is demonstrated with various examples and simulations involving both discrete and continuous data.
Analysis of the artificial viscosity in the smoothed particle hydrodynamics modelling of regular waves

ABSTRACT This paper considers the effect of artificial viscosity in smoothed particle hydrodynamics (SPH) computations of six different regular waves. The purpose is to improve the modelling of physically real effects and thereby make SPH a more attractive modelling option. The essence of the proposed method is to avoid running the simulation with different values of the empirical coefficient used in artificial viscosity in order to find the optimum value of this parameter for a given problem. Thorough calibration of the SPH's numerical parameters is performed through the comparison between numerical and experimental data. Among the various parameters involved, the smoothing length and the particle resolution are important in shaping the results. The analysis confirms that when the ratio of particle spacing to smoothing length and the particle resolution useful for different computational domains have been defined, the empirical coefficient depends only on the type of wave breaking in term of the Irribarren number.
Models of large scale structure

The ingredients required to construct models of the cosmic large scale structure are discussed. Input from particle physics leads to a considerable simplification by offering concrete proposals for the geometry of the universe, the nature of the dark matter and the primordial fluctuations that seed the growth of structure. The remaining ingredient is the physical interaction that governs dynamical evolution. Empirical evidence provided by an analysis of a redshift survey of IRAS galaxies suggests that gravity is the main agent shaping the large-scale structure. In addition, this survey implies large values of the mean cosmic density, ? 0.5, and is consistent with a flat geometry if IRAS galaxies are somewhat more clustered than the underlying mass. Together with current limits on the density of baryons from Big Bang nucleosynthesis, this lends support to the idea of a universe dominated by non-baryonic dark matter. Results from cosmological N-body simulations evolved from a variety of initial conditions are reviewed. In particular, neutrino dominated and cold dark matter dominated universes are discussed in detail. Finally, it is shown that apparent periodicities in the redshift distributions in pencil-beam surveys arise frequently from distributions which have no intrinsic periodicity but are clustered on small scales.
Discretized fractional calculus

For the numerical approximation of fractional integrals $I^\alpha f(x) = \frac{1}{{\Gamma (\alpha )}}\int_0^x {(x - s)^{\alpha - 1} f(s)ds\qquad (x \geqq 0)} $ with $f(x) = x^{\beta - 1} g(x)$, g smooth, we study convolution quadratures. Here approximations to $I^\alpha f(x)$ on the grid $x = 0,h,2h, \cdots ,Nh$ are obtained from a discrete convolution with the values of f on the same grid. With the appropriate definitions, it is shown that such a method is convergent of order p if and only if it is stable and consistent of order p. We introduce fractional linear multistep methods: The $\alpha $th power of a pth order linear multistep method gives a pth order convolution quadrature for the approximation of $I^\alpha $. The paper closes with numerical examples and applications to Abel integral equations, to diffusion problems and to the computation of special functions.
Elastic Energy of an Ellipsoidal Inclusion in an Infinite Solid

An exact solution in closed form is presented for the displacements, stresses and total elastic energy for the problem of an ellipsoidal isotropic inclusion bonded to an isotropic body of infinite extent when the inclusion and the infinite solid have uniformly distributed changes in their stress‐free specific volumes. The physically important details of the dependence of the total strain energy of the two materials upon the shape and volume of the inclusion, the elastic moduli of the two isotropic materials and the changes of specific volume, are included. The solution is indicated for the stresses and displacements for the case where the material at infinity is, in addition to the above condition, in a homogeneous state of stress whose principal directions are parallel to the axes of the cavity.
Magnetic field depression at the Earth's surface during energetic neutral atom emission fade‐out in the inner magnetosphere

[1] Using data from the high-energy neutral atom (HENA) imager onboard the IMAGE satellite, we examined the relation between the SYM-H index and the ring current energy during a storm main phase. The energy range of the energetic neutral atom (ENA) flux data used here is 16–120 keV for hydrogen and <180 keV for oxygen. From the data for the period 2000–2002, we selected 24 storm main phase events during which the IMAGE satellite was located at a geomagnetic latitude of ≥45° and a geocentric distance of ≥6 RE. According to the Dessler-Parker-Sckopke (DPS) equation, the ring current energy is expected to increase as the SYM-H index decreases. When the ENA energy flux is superimposed as a function of the SYM-H index for all 24 events, their overall correlation is negative; that is, the relation between the ENA energy flux and the SYM-H index is generally consistent with the DPS equation. However, an analysis of individual events showed only 10 events (42%) in which the ENA energy flux was negatively correlated with the SYM-H index (negative correlation events). There were 10 events showing no clear correlation between the ENA energy flux and the SYM-H index (no correlation events) and 4 events which contradicted the DPS equation (positive correlation events). In the superimposed plot, we noted that a smooth curve can be drawn for an upper limit of the data distribution, and data from the no correlation or positive correlation events create downward branches in the distribution. These observational results are not explained by the conventional DPS equation but by the “generalized” DPS equation, which includes a term representing energy stored in the stretched magnetic field. We can reasonably presume that the stretched magnetic field prevents energetic particles from being injected into the ring current. From the generalized DPS equation, we conclude that the total (kinetic and magnetic) energy stored in the stretched field and ring current loss mechanisms are important for understanding the relation between the ground magnetic field variation and ring current energy variation.
Seasonal and Interannual Variations of Diurnal Cycles of Wind and Cloud Activity Observed at Serpong, West Jawa, Indonesia

In this paper, the seasonal changes in the diurnal variations of wind and the cloud activity at Serpong (106.7°E, 6.4°S), near Jakarta, are climatologically described. In the dry season (May-October), diurnal variation of wind accompanied with sea-land breeze circulation was prominent. In the rainy season (November-April), the diurnal variation was consistent with sea-land breeze circulation, but was not as clear as that in the dry season. The peak time of the northerly in the rainy season, similarly to that of the sea breezes at Serpong in the low level (below 1.0 km height), was earlier than that in the dry season. The maximum time in the climatological diurnal variation of the surface temperature at Serpong in the rainy season was earlier than that in the dry season. The vertical structure which was consistent with sea breeze circulation was clearer when the prevailing (daily-mean) wind was weaker in the rainy season. These results are consistent with the features of the local circulation; in other words, the local circulation depends on the diurnal variation of surface temperature and is prominent when the prevailing wind is weak. The typical diurnal variation of the wind in the rainy season was unclear when the prevailing northwesterly to westerly was strong around Serpong. Interannual variation of the diurnal variation could be detected in the transitional period from the dry to the rainy season. Cloud activity had prominent diurnal variation over West Jawa in the rainy season and was active in the early evening over land, particularly, in the mountainous area in the south of Serpong. When cloud activity was active over the mountainous area, the northerly below 1.0 km in height was prominent at Serpong, which is consistent with the feature that the development of a local cloud system is accompanied with local circulation.
Effects of Nitrite and Phosphate Replacements for Clean-Label Ground Pork Products

Abstract We investigated the effects of different phosphate replacements on the quality of ground pork products cured with sodium nitrite or radish powder to determine their potential for achieving clean-label pork products. The experimental design was a 2×5 factorial design. For this purpose, the ground meat mixture was assigned into two groups, depending on nitrite source. Each group was mixed with 0.01% sodium nitrite or 0.4% radish powder together with 0.04% starter culture, and then processed depending on phosphate replacement [with or without 0.5% sodium tripolyphosphate; STPP (+), STPP (−), 0.5% oyster shell calcium (OSC), 0.5% citrus fiber (CF), or 0.5% dried plum powder (DPP)]. All samples were cooked, cooled, and stored until analysis within two days. The nitrite source had no effect on all dependent variables of ground pork products. However, in phosphate replacement treatments, the STPP (+) and OSC treatments had a higher cooking yield than the STPP (−), CF, or DPP treatments. OSC treatment was more effective for lowering total fluid separation compared to STPP (−), CF, or DPP treatments, but had a higher percentage than STPP (+). The STPP (+) treatment did not differ from the OSC or CF treatments for CIE L* and CIE a*. Moreover, no differences were observed in nitrosyl hemochrome content, lipid oxidation, hardness, gumminess, and chewiness between the OSC and STPP (+) treatments. In conclusion, among the phosphate replacements, OSC addition was the most suitable to provide clean-label pork products cured with radish powder as a synthetic nitrite replacer.
Discovery and photometric study of the new in-the-gap SU UMa Dwarf Nova Var 73 Dra

We present the discovery and the first investigation of the new dwarf nova Var 73 Dra. We carried out monitoring and time-resolved CCD observations in 2001 August-October and detected several normal outbursts with a recurrence time of about 7-8 days and one slightly brighter superoutburst with a "plateau" phase that lasted 13 days. Our photometry during the superoutburst clearly shows the presence of superhumps with the period 0.0954 (0:0001) day (although the one-day alias period, 0.1053 d, could not be ruled out). So, the observed features allow us to classify Var 73 Dra as a new SU UMa-type dwarf nova within the well-known gap of orbital period distribution of cataclysmic variables.
Periodic Time-Dependent Predator-Prey Systems

The general system of differential equations describing predator-prey dynamics is modified by the assumption that the coefficients are periodic functions of time. By use of standard techniques of bifurcation theory, as well as a recent global result of Rabinowitz, it is shown that this system has a periodic solution (in place of an equilibrium) provided the long term time average, of the predator’s net, unihibited death rate is in a suitable range. The bifurcation is from the periodic solution of the time-dependent logistic equation for the prey (which results in the absence of any predator). Numerical results which clearly show this bifurcation phenomenon are briefly discussed.
Multiple hamartomas of the oral cavity with bifid tongue and cleft palate: A unique observation

Background: Hamartomas are developmental tumor-like malformations, comprising a mixture of cytologically mature tissues that are indigenous to their anatomical location. Within the oral cavity, these lesions are usually multifocal, relatively small, and asymptomatic, and have been frequently linked to present as a manifestation of the oro-facial-digital-syndrome. Case Presentation: A 2-day-old female newborn was referred with two masses protruding from the oral cavity, feeding difficulties, and dribbling of milk during feeding. The patient had no dysmorphic features and no obvious associated anomalies. On careful examination, there was one mass protruding from the undersurface of a bifid tongue with another larger mass that seemed to originate from the hard palate. Complete surgical excision of both masses and repair of the bifid tongue were done to relieve the baby’s feeding difficulties. Histopathological examination of both specimens confirmed the diagnosis of multiple hamartomas. Conclusion: The occurrence of multiple and large oral hamartomas in newborns might result in feeding difficulties that necessitate urgent surgical intervention. The association of lingual and palatal hamartomas, with bifid tongue and cleft palate, is a unique observation that is not reported in the English literature.