Miracle-dz/UniFAR-FTUs huggingface dataset:
An Improved Algorithm on Frequent Subgraph Query

This paper studies the frequent subgraph query issues on graph data set. Combining with the approach that frequent subtree extend to frequent subgraphs proposed by Xian-Tong Li, we propose a new algorithm. This algorithm improved its storage structure avoiding direct subgraph isomorphism judgment, reduced the stability requirements on graph set, and enchanced the overall efficiency of the algorithm.
L-shell photoionization cross-sections for Fe XIX and Fe XX recombination rate coefficients

High-quality atomic data concerning the interaction of photons with highly ionized ions of iron are an essential requirement in the modelling of X-ray emission from astrophysical plasmas. Consequently a detailed study of the photoionization of the ground-state fine-structure levels (2s22p43P2,0,1) of Fe XIX has been undertaken, and a set of high-resolution cross-sections for photoionization of each of these levels obtained. We have considered both the total and partial cross-section cases, with the latter restricted to those instances where the residual ion is left in one of the energetically lowest 23 Jπ (12 LSπ) states of Fe XX. The calculation was performed by applying the Breit–Pauli R-matrix codes using a sophisticated representation of these 23 target-states. This approach allows for the possibility of fine-structure splitting in both thresholds and resonances, as well as incorporating any coupling between target-states with different LS symmetries through the inclusion of the spin–orbit operator. A significant amount of such coupling is discovered in the present investigation, and is responsible for a background cross-section whose magnitude is lower than that determined in previous LS-coupling calculations by more than a factor of 2. Extensive resonance structure is also resolved, including shape resonances in the 133 148 Ryd photon energy region. Such structure has not been resolved in any previous investigation and is of extreme importance in the modelling of X-ray emission plasmas. Using the derived photoionization cross-section data, recombination rate coefficients are calculated using the Milne relation, for the case of an electron recombining with Fe XX in the ground state to form Fe XIX existing in each of the fine-structure ground-state levels. These recombination rates are summarized over a temperature range of 50 000 to 107 K. To supplement these data further we also present a set of energy levels and oscillator strengths for Fe XX.
Delayed least mean squares (cid:12)lters suppressing the radio frequency interference in cosmic rays radio detection

Extensive Air Showers (EAS), initiated by Ultra-High-Energy Cosmic Rays (UHECRs), generate geo-synchrotron and geo-magnetic radiations and they are, also, the source of excess charge processes. In the frequency range of 10 to 100 MHz, coherent radiation is formed. Many experiments use the radio detection technique for studying EAS features. The Auger Engineering Radio Array (AERA), part of the Pierre Auger Observatory, uses hundreds of radio antennas working in the frequency range of 30 to 80 MHz to support the investigation of UHECRs together with the standard surface and (cid:13)uorescence detectors. The AERA radio frequency range is signi(cid:12)cantly contaminated by the human-made and usually narrow-band Radio Frequency Interference (RFI), e.g., short-wave radio transmitters. The presence of RFIs in the detected signals increases the ratio of spurious triggers; in consequence, empty data in(cid:13)ate the databases. This study proposes replacing the currently used IIR-notch nonadaptive (cid:12)lter by the delayed version of the well-known Least Mean Squares (LMS) algorithm, which o(cid:11)ers crucial advantage adjustment. The current study implemented 32/64-stage Delay Least Mean Squares (DLMS) (cid:12)lters on cost-e(cid:11)ective Cyclone ﬁ IV and Cyclone ﬁ V as non-canonical Finite Input Response (FIR) with a su(cid:14)cient safety margin for a global clock being at least 20% higher than 200 MHz, which equals the ADC sampling frequency. ' 2022 Sharif University of Technology. All rights reserved.
Nonradial type II blow up for the energy-supercritical semilinear heat equation

We consider the semilinear heat equation in large dimension d ≥ 11 ∂tu = ∆u + |u| p−1 u, p = 2q + 1, q ∈ N on a smooth bounded domain Ω ⊂ R d with Dirichlet boundary condition. In the supercritical range p ≥ p(d) > 1 + 4 d−2 we prove the existence of a countable family (u l) l∈N of solutions blowing-up at time T > 0 with type II blow up: u l (t) L∞ ∼ C(T − t) −c l with blow-up speed c l > 1 p−1. They concentrate the ground state Q being the only radially and decaying solution of ∆Q + Q p = 0: u(x, t) ∼ 1 λ(t) 2 p−1 Q x − x0 λ(t) , λ ∼ C(un)(T − t) c l (p−1) 2 at some point x0 ∈ Ω. The result generalizes previous works on the existence of type II blow-up solutions, either constructive [14, 15, 35] or nonconstructive [25, 36], which only existed in the radial setting and relied on parabolic arguments. The present proof uses robust nonlinear tools instead, based on energy methods and modulation techniques in the continuity of [3, 32]. This is the first non-radial construction of a solution blowing up by concentration of a stationary state in the supercritical regime, and provides a general strategy to prove similar results for dispersive equations or parabolic systems and to extend it to multiple blow ups.
Simple Regressions with Linear Time Trends

Simple regressions of two trend stationary time series are considered. As the linear trend dominates the stochastic components the rates of convergence and the limiting distributions of ordinary least squares statistics are exactly the same as in the case of cointegrated regressions with drifts. In particular, asymptotic standard normal t statistics are readily available. Hence, asymptotic inference requires no distinction between simple regressions of trend stationary series and of cointegrated variables with drifts.
Developmental Processes and Stages in the Acquisition of Cardinality

This is a study of the level of children's understanding of cardinality, focusing on the difference between a true cardinality response and the application of a mechanically learned rule. The authors also evaluate and discuss the possible relationship between cardinality and counting. The subjects were two groups of 32 preschool children, ranging in age from 4 years 3 months to 6 years 3 months. Experimental methodology included two large sets of tests (elements-cardinal vs cardinal-elements), using both numbers and vowels with forward vs backward counting, and visual vs verbal presentation conditions. Results show that cardinality responses are affected by both the direction and nature of the elements in the counting sequence. Scrutiny of errors committed in the various tests enables us to suggest six stages in the acquisition of cardinality. Although there appears to be a developmental dependency between counting and cardinality, this relationship is not significant in all cases.
Negative group velocity from resonances in two-dimensional phononic crystals

We investigate two routes to obtain negative group velocity bands in two-dimensional phononic crystal structures. The negative dispersion originates from the resonances of sub-wavelength building blocks and as such, the system should be regarded as acoustic metamaterials. The first kind of acoustic metamaterial exhibits effectively negative bulk modulus and negative mass density simultaneously. Monopolar and dipolar Mie resonances are combined to achieve an effective medium with negative refractive index. In particular, we present a double negative metamaterial for airborne sonic waves. We then show that we can obtain negative group velocity from quadrupole resonances, and the result is explained using the quasi-static approximation. The negative dispersion in quadrupole bands cannot be described by standard effective medium theories even though the frequency can be very low.
A connection between quantum Hilbert-space and classical phase-space operators

We develop a general `classicalization' procedure that links Hilbert-space and phase-space operators, using Weyl's operator. Then we transform the time-dependent Schrödinger equation into a phase-space picture using free parameters. They include position Q and momentum P. We expand the phase-space Hamiltonian in an ℏ-Taylor series and fix parameters with the condition that coefficients of ℏ0, -iℏ1 ∂/∂Q and iℏ1 ∂/∂P vanish. This condition results in generalized Hamilton equations and a natural link between classical and quantum dynamics, while the quantum motion-equation remains exact. In this picture, the Schrödinger equation reduces in the classical limit to a generalized Liouville equation for the quantum-mechanical system state. We modify Glauber's coherent states with a suitable phase factor S(Q,P,t) and use them to obtain phase-space representations of quantum dynamics and quantum-mechanical quantities.
Optical frequency signal detection through surface plasmon polaritons

We demonstrated experimentally that an optical frequency signal can be detected through surface plasmon polaritons (SPPs) using an optical heterodyne technique. We fabricated an SPP detector consisting of a Au/Si Schottky diode with seven 10-μm-long and 150-nm-wide parallel slits (a multi-slit grating). When two beams of light with slightly different wavelengths irradiated the multi-slit grating of the SPP detector, a beat signal, corresponding to the optical frequency signal, was clearly observed.
A three-field formulation of the Poisson problem with Nitsche approach

We modify a three-field formulation of the Poisson problem with Nitsche approach for approximating Dirichlet boundary conditions. Nitsche approach allows us to weakly impose Dirichlet boundary condition but still preserves the optimal convergence. We use the biorthogonal system for efficient numerical computation and introduce a stabilisation term so that the problem is coercive on the whole space. Numerical examples are presented to verify the algebraic formulation of the problem.
Aspects of a Northern Hemisphere Atmospheric Blocking Climatology

Abstract A comprehensive climatology of Northern Hemisphere blocking is described based on a PV–θ wave-breaking index at the latitude of the climatological storm track and using the 40-yr ECMWF Re-Analysis (ERA-40) dataset. The general characterization of blocking regions is in agreement with most other studies, though more detail is provided here. In the annual average, blocking is most prevalent in the large region from the eastern Atlantic Ocean through Europe to central Asia with a secondary region in the central and eastern Pacific Ocean. Using a blocking criterion with the requirement for both longitudinal extent and temporal persistence, the peak in the frequency is in the Scandinavian region, where 24% of the days are characterized by blocking. In the east Pacific maximum, the corresponding number is 7%. However, there is considerable and very important interannual variability. The decay rate in the number of blocking events lasting at least a specified number of days is significantly less over Eu.
The $\gamma$-Vectors of Pascal-like Triangles Defined by Riordan Arrays

We define and characterize the $\gamma$-matrix associated to Pascal-like matrices that are defined by ordinary and exponential Riordan arrays. We also define and characterize the $\gamma$-matrix of the reversions of these triangles, in the case of ordinary Riordan arrays. We are led to the $\gamma$-matrices of a one-parameter family of generalized Narayana triangles. Thus these matrices generalize the matrix of $\gamma$-vectors of the associahedron. The principal tools used are the bivariate generating functions of the triangles and Jacobi continued fractions.
On the Process of Speech Perception

The process of speech perception is analyzed into three main operations: (1) translation of the speech signal into form suitable for the nervous system, (2) identification of discrete speech elements, and (3) comprehension of meaning. The first operation appears to correspond roughly to the transformation made by the sound spectrograph. The second may be carried out by the neural equivalent of a set of matched filters. The third appears to involve a neural form of cross‐correlation that exhibits some of the properties of the analogous electronic process.
An efficient method for block low-rank approximations for kernel matrix systems

In the iterative solution of dense linear systems from boundary integral equations or systems involving kernel matrices, the main challenges are the expensive matrix-vector multiplication and the storage cost which are usually tackled by hierarchical matrix techniques such as $\mathcal{H}$ and $\mathcal{H}^2$ matrices. However, hierarchical matrices also have a high construction cost that is dominated by the low-rank approximations of the sub-blocks of the kernel matrix. In this paper, an efficient method is proposed to give a low-rank approximation of the kernel matrix block $K(X_0, Y_0)$ in the form of an interpolative decomposition (ID) for a kernel function $K(x,y)$ and two properly located point sets $X_0, Y_0$. The proposed method combines the ID using strong rank-revealing QR (sRRQR), which is purely algebraic, with analytic kernel information to reduce the construction cost of a rank-$r$ approximation from $O(r|X_0||Y_0|)$, for ID using sRRQR alone, to $O(r|X_0|)$ which is not related to $|Y_0|$. Numerical experiments show that $\mathcal{H}^2$ matrix construction with the proposed algorithm only requires a computational cost linear in the matrix dimension.
Observations of quasars with the International Ultraviolet Explorer satellite.

The paper deals with the spectra of six quasars, ranging in redshift from 0.23 to 2.04, obtained with the 45-cm telescope mounted on the IUE satellite. The average emission-line intensity ratio for L-alpha to H beta and the detection of higher-order Lyman emission lines in two objects are found to be inconsistent with a simple optically thick recombination model. The Lyman and Balmer line velocity profiles are identical. The emission lines in 3C 351 can be decomposed into sharp and broad components, with the sharp lines consistent with the recombination model.
Audibility region of combination tones

This paper describes research on combination tones of the type f1 − k (f2 − f1. Such tones are audible during stimulation by the two frequency components f1 and f2, with f1 < f2. The results of the experiments suggest that these combination tones are audible only in a restricted frequency region below f1. The lower limit of this “audibility region,” for the combination tone 2f1 − f2 (k = 1), was determined primarily by the level of the lower stimulus component L1 and additionally by L2. The width of the audibility region appeared to be highly subject dependent. The lowest stimulus level for which 2f1 − f2 was audible was 15–20 dB SL if both stimulus components had equal levels. If the lower component was set at 40 dB, then the higher one could be reduced to 4 dB before 2f1 − f2 reached threshold. Higher‐order combination tones could be perceived up to k = 5 or 6. At 40 dB SL, the lower limit of the audibility region was approximately the same regardless of the order (i.e., independent of k). The width of the audibility region could not be explained completely by the amount of interaction of the mechanical stimulation patterns corresponding to f1 and f2. In addition, it is demonstrated that these combination tones may play a misleading part in masking experiments. The detection threshold of a simple tone masked by another simple tone may be determined by the detection of a combination tone of the type f1 − k (f2 − f1), even at a low level of the masker.
Changes in the bioluminescence of firefly under pulsed and static magnetic fields

The effects of a pulsed train magnetic field (PMF) and 10-T order of static magnetic fields on firefly bioluminescence were investigated on two species, Luciola cruciata and Luciola lateralis. Strong static magnetic field exposure experiments were carried out with a time-resolved spectroscopy, and the firefly bioluminescence spectrum showed a redshift in the range of 540–580nm when the firefly emitted pulses under the 10-T magnetic field. Separately from this effect, a transient decrease in the firefly’s emission intensity was observed right after being exposed to the static magnetic fields of up to 10 T. On the other hand, the utilized PMFs stimulated and enhanced the bioluminescence of Luciola cruciata. The PMF with 250–325 T/s at 1.3–10 Hz increased both the firefly’s pulsed density and frequency. It was speculated that the magnetically induced current inside the firefly affected its nervous system or the photochemical processes in the light producing organ, while the diamagnetic torque forces, which w.
A direct nonlinear inversion of primary wave data reflecting from extended, heterogeneous media

Wave events that have reflected once from an extended, heterogeneous medium may be approximated, to varying degrees of accuracy, with subsets of terms of the forward scattering series and a homogeneous reference medium. Two such primary approximations, when inverted order-by-order, produce nonlinear, series-form algorithms that directly determine the medium from primary data. These forward and inverse expressions are remarkably symmetric; in fact, under the assumption of a depth-varying perturbation, they form pairs of nonlinear integral transforms back and forth between the data and the perturbation.
Toward a Model for Speech Recognition

An approach to the design of a machine for the recognition and synthesis of speech is proposed, with particular emphasis on problems of acoustical analysis. As a recognizer, the proposed machine accepts a speech wave at its input and generates a sequence of phonetic symbols at its output; as a synthesizer it accepts a sequence of symbols at its input and generates speech wave. Coupling between the acoustical speech signal and the machine is achieved through two peripheral units: one an analog filter set or equivalent, and the other a model of the vocal tract. Between the analog filters and the phonetic output the signal undergoes an intermediate form of representation that is related to vocal‐tract configurations and excitations but is not necessarily described specifically in these terms. Each stage of analysis is performed by synthesis of a number of alternative signals or patterns according to rules stored within the machine and by comparison of the synthesized patterns with the input signals that are .
Cauchy problems for some classes of linear fractional differential equations

Cauchy problems for a class of linear differential equations with constant coefficients and Riemann-Liouville derivatives of real orders, are analyzed and solved in cases when some of the real orders are irrational numbers and when all real orders appearing in the derivatives are rational numbers. Our analysis is motivated by a forced linear oscillator with fractional damping. We pay special attention to the case when the leading term is an integer order derivative. A new form of solution, in terms of Wright’s function for the case of equations of rational order, is presented. An example is treated in detail.
Electroluminescence from n-ZnO nanowires/p-GaN heterostructure light-emitting diodes

The investigation explores the fabrication and characteristics of ZnO nanowire (NW)/p-GaN/ZnO NW heterojunction light-emitting diodes (LEDs). Vertically aligned ZnO NWs arrays were grown on the p-GaN substrate. The n-p-n heterojunction LED was fabricated by combining indium tin oxide/glass substrate with the prepared ZnO NWs/p-GaN substrate. The symmetrical rectifying behavior demonstrates that the heterostructure herein was formed with two p-n junction diodes and connected back to back. The room-temperature electroluminescent emission peak at 415 nm was attributed to the band offset at the interface between n-ZnO and p-GaN and defect-related emission from ZnO and GaN. Finally, the photograph indicated the LED clearly emitted blue light.
Index and Spectral Theory for Manifolds with Generalized Fibred Cusps

Generalizing work of W. M\"uller we investigate the spectral theory for the Dirac operator D on a noncompact manifold X with generalized fibred cusps $$ C(M)=M\times [A,\infty[_r, g= d r^2+ \phi^*g_Y+ e^{-2cr}g_Z, $$ at infinity. Here $\phi:M^{h+v}\to Y^h$ is a compact fibre bundle with fibre Z and a distinguished horizontal space HM. The metric $g_Z$ is a metric in the fibres and $g_Y$ is a metric on the base of the fibration. We also assume that the kernel of the vertical Dirac operator at infinity forms a vector bundle over $Y$. Using the ``$\phi$-calculus'' developed by R. Mazzeo and R. Melrose we explicitly construct the meromorphic continuation of the resolvent $G(\lambda)$ of D for small spectral parameter as a special ``conormal distribution''. From this we deduce a description of the generalized eigensections and of the spectral measure of D. Complementing this, we perform an explicit construction of the heat kernel $[\exp(-tD^2)]$ for finite and small times t, corresponding to large spectral parameter $\lambda$. Using a generalization of Getzler's technique, due to R. Melrose, we can describe the singular terms in the heat kernel expansion and prove an index formula for D, calculating the extended $L^2$-index of D in terms of the usual local expression, the family eta invariant for the family of vertical Dirac operators at infinity and the eta invariant for the horizontal ``Dirac'' operator at infinity.
Modeling Branch Length of Larch Tree Using Linear Mixed-Effects Models

In this study, the sample data was based on 2190 branch length samples of 30 trees from dahurian larch (Larix gmelinii Rupr.) plantations located in Wuying forest bureau in Heilongjiang Province. A second order polynomial equation with linear mixed-effects was used for modeling branch length of larch tree. The LME procedure in S-Plus is used to fit the mixed-effects models for the branch length data. The results showed that the polynomial model with three random parameters could significantly improve the model performance. The fitted mixed effects model was also evaluated using mean error, mean absolute error, mean percent error, and mean absolute percent error. The mixed model was found to predict branch length better than the original model fitted using ordinary least squares based on all errors. The application of mixed branch length model not only showed the mean trends of branch length, but also showed the individual difference based on variance-covariance structure.
Diurnal Variations of Warm-Season Precipitation over Northern China

Abstract This study examines the diurnal variations of the warm-season precipitation over northern China using the high-resolution precipitation products obtained from the Climate Prediction Center’s morphing technique (CMORPH) during May–August of 2003–09. The areas of focus are the Yanshan–Taihangshan Mountain ranges along the east peripheries of the Loess and Inner Mongolian Plateaus and the adjacent North China Plains. It is found that the averaged peak in local precipitation begins early in the afternoon near the top of the mountain ranges and propagates downslope and southeastward at a speed of ∼13 m s−1. The peak reaches the central North China Plains around midnight and the early morning hours resulting in a broad area of nocturnal precipitation maxima over the plains. The diurnal precipitation peak (minimum) is closely collocated with the upward (downward) branch of a mountain–plains solenoid (MPS) circulation. Both the MPS and a low-level southwesterly nocturnal jet are likely to be jointly resp.