Miracle-dz/UniFAR-FTUs huggingface dataset:
Layer Potential Analysis for Pseudodifferential Matrix Operators in Lipschitz Domains on Compact Riemannian Manifolds: Applications to Pseudodifferential Brinkman Operators

R n, n≥ 3, and with L2 boundary data. Shen [47] studied the L p Dirichlet problem for the Stokes system in Lipschitz domains in Rn, n≥ 3, and obtained optimal estimates when n= 3, as well as a weak estimate of solutions for certain range of p when n≥ 4 (see also [48]). Mitrea and Taylor [40–45] developed the potential theory for elliptic operators on Lipschitz domains in Riemannian manifolds and used this theory to treat the
Comparative numerical integration of simple atmospheric models on a spherical grid

The non-divergent barotropic model, the two-layer quasi-geostrophic baroclinic model, and the two-layer balanced baroclinic model of variable static stability are integrated in parallel on a spherical grid with comparable boundary and initial conditions for the case of 00 GCT, 3 7 December 1957. The integrations of the barotropic and quasigeostrophic models show the expected accuracy decay to 72 hr, characterized by excessive momentum transport into the jet and an overall failure to predict significant baroclinic development. The balanced model displays an initially similar behavior, although the vertical motions are about twice those of the quasi-geostrophic case. Beyond 12 hr the balanced model's vertical motions become excessively cellular and of increased magnitude, and a progressively serious distortion of the solutions takes place by 24 hr. The energy transformations of the variable-stability model indicate a disturbance evolution significantly different from that of the quasi-geostrophic model, although beyond 12 hr these transformations are themselves seriously influenced by the computed vertical motions. A number of recommendations for further tests are made, of which the improvement of the finite-difference schemes is probably the most important. DOI: 10.1111/j.2153-3490.1963. tb01404.x
Limiting diffusion approximations for the many server queue and the repairman problem

We shall consider a many server (multiple channels in parallel) queueing process in which customers arrive at the queue according to a Poisson process. The service times are assumed to be independent and exponentially distributed. As usual, the service times are independent of the arrival process. We assume that no server is idle if there is a customer waiting, but that otherwise the service discipline is arbitrary. If there are n servers and we let Xn (t) denote the number of customers waiting or being served at time t, then it is well known that Xn (t) is a birth and death process with stationary transition probabilities. A very comprehensive analysis of this many server queue from the point of view of birth and death processes has been carried out by Karlin and McGregor [5].
Transmission by Haze and Fog in the Spectral Region 0.35 to 10 Microns

Two independent methods were used: direct spectrophotometry through the transparent windows of the atmospheric gases, and measurement of the number and diameter of the water droplets, followed by a Mie-theory calculation of the spectral transmittance. Results from the two methods are in good agreement when the media are sufficiently homogeneous, as for a quiet haze or fog and artificial smoke.The following kinds of atmospheres were considered: hazes (optical density per km in the visible spectrum is less than 2); a small number of small-drop fogs (optical density per km less than 10); evolving fogs (which have changing distributions of drop-diameters); nonevolving, slightly selective fogs; artificial smokes. In addition, some information is given on the statistical distribution of drop-diameters.It was found that the transmission of haze increased markedly with increasing wavelength, from the visible to 10 microns, but this marked increase was not found for fogs.
The Distribution of Node Degree in Maximum Spanning Trees

We use Monte Carlo simulation to study the distribution of node degree in the Euclidean maximum spanning tree. Extrapolating from our experiments, we conjecture that, for uniformly distributed data, the asymptotic low-data-density probability of node degree k is proportional to k m 2 . This conjecture, if true, has implications for detecting outliers and testing random number generators.
Stellar Content of the Galactic Starburst Template NGC 3603 from Adaptive Optics Observations

We present near-infrared adaptive optics imaging of the Galactic starburst template NGC 3603 and its stellar center HD 97950. There is clear evidence for the presence of stars down to 1 ℳ or less. No cutoff or turnover in the initial mass function is evident. Applying theoretical models of the pre-main-sequence evolution of intermediate-mass stars to the observed color-color diagram, the color-magnitude diagram, and the luminosity function, we constrain both the age distribution and the initial mass function. Within the systematic errors, this initial mass function follows a Salpeter power law with index Γ ≤ -0.73 down to the observational limit of less than 1 ℳ. The stars with less than 4 ℳ appear to be younger than 106 yr, in contrast to previous age determinations of the high-mass content of HD 97950.
Modeling of the nonlinear growth of neoclassical tearing modes

The nonlinear growth of neoclassical tearing modes is studied numerically. In the present computational model the perturbed bootstrap current, as well as the nonlinear coupling between different harmonics of the same helicity, are included, and the large aspect-ratio tokamak approximation is used. This work is focused on the nonlinear growth time and the saturated width of the magnetic island. The perturbed bootstrap current is found to play a destabilizing role in the nonlinear island as in previous analytical theories. For sufficiently large islands, the island width at saturation is not linearly proportional to the fraction of the bootstrap current. The formation of the island leads to a near constant decrease in plasma pressure in the region between the magnetic axis and the island. The simulated island growth time, as well as the saturated island width, agree very well with experimental observations.
Chromosome Evolution of the Liolaemus monticola (Liolaemidae) Complex: Chromosomal and Molecular Aspects

Simple Summary Chromosome variation is highly relevant for evolution because chromosomal mutations can influence speciation. Here, we assessed population cytogenetics in Liolaemus monticola, a lizard endemic to Chile that consists of several chromosomal races with highly polymorphic chromosome rearrangements. We sampled individuals from the northernmost distribution of the species to obtain chromosomes and mitochondrial gene sequences and compared the samples to previously published data from other populations across the distribution. Our results show the existence of seven differentiated races of L. monticola, each with unique chromosome characteristics and high levels of polymorphism. Interestingly, the geographical delimitation of the races is associated with the presence of rivers that could represent barriers to gene flow. Thus, our study highlights the importance of chromosomal mutations for population differentiation, and in turn, speciation. Abstract Chromosomal rearrangements can directly influence population differentiation and speciation. The Liolaemus monticola complex in Chile is a unique model consisting of several chromosome races arranged in a latitudinal sequence of increasing karyotype complexity from south to north. Here, we compared chromosomal and mitochondrial cytochrome b data from 15 localities across the northern geographic distribution of L. monticola. We expanded the distribution of the previously described Multiple Fissions race (re-described as MF2), in the Coastal range between the Aconcagua River and the Petorca River, and described a new Multiple Fissions 1 (MF1) race in the Andean range. Both races present centric fissions in pairs 1 and 2, as well as a pericentric inversion in one fission product of pair 2 that changes the NOR position. Additionally, we detected a new chromosomal race north of the Petorca River, the Northern Modified 2 (NM2) race, which is polymorphic for novel centric fissions in pairs 3 and 4. Our results increase the number of chromosomal races in L. monticola to seven, suggesting a complex evolutionary history of chromosomal rearrangements, population isolation by barriers, and hybridization. These results show the relevant role of chromosome mutations in evolution, especially for highly speciose groups such as Liolaemus lizards.
Unusual Depletions toward the SMC Star Sk 155—Differences in Dust Composition in the SMC Interstellar Medium?

We report initial results from an analysis of Hubble Space Telescope/Space Telescope Imaging Spectrograph echelle spectra of interstellar absorption toward Sk 155, located in the "wing" region of the SMC. There are at least 12 Milky Way (disk and halo) and at least 25 SMC components discernible in the profiles of various neutral and singly ionized species. Fits to the line profiles yield column densities and relative elemental abundances for the individual components. In the SMC components, the depletions of Fe and Ni range from mild ([Fe, Ni/Zn] ~ -0.3 to -0.8 dex) to severe ([Fe, Ni/Zn] ~ -1.7 dex); Mg and Si, however, appear to be essentially undepleted ([Mg, Si/Zn] ~ -0.1 to +0.2 dex) throughout. The combination of severe depletion for Cr, Mn, Fe, and Ni and negligible depletion for Mg and Si has not been seen in any Galactic sight line. If Si is generally undepleted in the SMC, then current models of the SMC dust—which rely heavily on silicates—will have to be reconsidered; oxides and/or metallic grains may dominate. We briefly discuss possible the implications of these SMC depletions for understanding the elemental abundances in QSO absorption-line systems.
Orbital Magnetic Moment in Superlattices of Transition Metals

The spin ( M s ) and orbital magnetic moments ( M o ) of a Co atom are calculated for various superlattices of Co atoms in fcc Pd or Cu matrix on the basis of the tight-binding model including s , p and d orbits, where the intraatomic multipole interaction between d electrons is taken into account with the Hartree-Fock approximation. A test calculation for pure Fe, Co and Ni with use of parameters obtained by fitting with the first-principles calculation shows that the method well describes the ratio M o / M s . Two types of enhancement of M o of the Co atom in superlattices are proposed based on a semi-quantitative calculation with assuming ferromagnetism. In the Pd matrix, the enhancement is shown to arise from the increase of the lattice parameter, which causes the narrowing of 3 d density of states; the atomic environment of a Co atom in the matrix, i.e., the numbers of neighboring Co or Pd atoms are the minor effect. In the Cu matrix, on the other hand, the difference in the effective hybridization i.
Stable Determination of Sound-soft Polyhedral Scatterers by a Single Measurement

We prove optimal stability estimates for the determination of a finite number of sound-soft polyhedral scatterers in R 3 by a single far-field measurement. The admissible multiple polyhedral scatterers satisfy minimal a priori assumptions of Lipschitz type and may include at the same time obstacles, screens and even more complicated scatterers. We characterize any multiple polyhedral scatterer by a size parameter h which is related to the minimal size of the cells of its boundary. In a first step we show that, provided the error e on the far-field measurement is small enough with respect to h, then the corresponding error, in the Hausdorff distance, on the multiple polyhedral scatterer can be controlled by an explicit function of e which approaches zero, as e → 0 + , in an essentially optimal, although logarithmic, way. Then, we show how to improve this stability estimate, provided we restrict our attention to multiple polyhedral obstacles and e is even smaller with respect to h. In this case we obtain an explicit estimate essentially of Holder type.
Light interaction with multilayer arbitrary anisotropic structure: an explicit analytical solution and application for subwavelength imaging

A systematic analytical approach to simulate the propagation of electromagnetic plane waves in multilayer anisotropic structures, where the layers can have arbitrary oriented optical axis, is presented. The explicit expressions for the vector polarizations of electric and magnetic fields inside a randomly oriented anisotropic medium are derived. The developed algorithm operates with analytic 4×4 matrices to calculate the transmission and reflection coefficients. This algorithm is suitable to investigate the near-field/far-field electromagnetic wave interaction at any angle of incidence for numerous intriguing applications. The procedure is applied to design anisotropic single and multilayer lenses for subwavelength imaging.
Determining The Value-at-risk In The Shadow Of The Power Law: The Case Of The SP-500 Index

In extant financial market models, including the Black-Scholes’ contruct, the dramatic events of October 1987 and August 2007 are totally unexpected, because these models are based on the assumptions of ‘independent price fluctuations’ and the existence of some ‘fixed-point equilibrium’. This paper argues that the convolution of a generalized fractional Brownian motion (into an array in frequency or time domain) and their corresponding amplitude spectra describes the surface of the attractor driving the evolution of prices. This more realistic approach shows that the SP-500 Index is characterized by a high long term Hurst exponent and hence by a ‘black noise’ with a power spectrum proportional to f-b (b > 2). In that set up, the above dramatic events are expected and their frequencies are determined. The paper also constructs an exhaustive frequency-variation relationship which can be used as practical guide to assess the ‘value at risk’.
Simple estimation of the mode of a multivariate density

The authors consider an estimate of the mode of a multivariate probability density using a kernel estimate drawn from a random sample. The estimate is defined by maximizing the kernel estimate over the set of sample values. The authors show that this estimate is strongly consistent and give an almost sure rate of convergence. This rate depends on the sharpness of the density near the true mode, which is measured by a peak index.
Multiwavelength Analysis of an X1.6 Flare of 2001 October 19

An X1.6 two-ribbon flare was observed on 2001 October 19 using the imaging spectrograph at the Solar Tower of Nanjing University. We obtained a time series of two-dimensional Hα line spectra. Combining the observations by the Nobeyama Radioheliograph (NoRH), the Transition Region and Coronal Explorer (TRACE), the Yohkoh soft X-ray telescope (SXT) and hard X-ray telescope (HXT), and the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO), we performed a multiwavelength analysis for this flare in detail. The hard X-ray (HXR) and radio time profiles for this event have a double-peaked structure. Four Hα bright kernels exist, two of which are identified as the conjugate footpoints of a loop, while the other two are probably the footpoints of two different loops that are closely related. We compared the spatial distribution of the HXR sources with that of the Hα kernels at the two peak times. The results show quite asymmetric HXR emission in the Hα kernels. We ascribe this asymmetric behavior to the magnetic mirroring effect. In addition, we found that different heating mechanisms (nonthermal electron beam vs. heat conduction) may apply to different Hα kernels. We also derived the velocity field and found that the maximum velocity tends to occur at the outer edge of the flare ribbons. This is consistent with the general scenario of two-ribbon flare models.
Magnetometer measurements from the Cassini Earth swing-by

Magnetometer data recorded by the Cassini spacecraft during the spacecraft's Earth swing-by maneuver in August 1999 are discussed. The primary purpose of this paper is to show the instrument's performance in detection of magnetic phenomena in a planetary environment. Companion papers put the data in a broader geophysical context. The low noise and high time resolution of the instrument coupled with the unusual orbit did produce new information about old phenomena (e.g., a whistler-like signal inside the near-subsolar magnetopause, lower hybrid noise in the current sheets around a magnetosheath field null, and sharp changes in the ion cyclotron wave spectrum between the boundary layer and magnetosphere proper). The detection of irregular isolated 1–2 s duration small-amplitude field strength dips in the vicinity of the nightside plasma trough appear to constitute a new discovery, tentatively identified as being evidence of plasmasphere interchange instability during a lull in background convection. The absolute scalar element of the instrument worked to plan, operating within 4 RE of Earth in parallel with the fluxgate sensors. In all respects, instrument performance bodes well for the Saturn orbital phase of the mission.
New critical values for the generalized t and generalized rank-sum procedures

Student's t test as well as Wilcoxon's rank-sum test may be inefficient in situations where treatments bring about changes in both location and scale. In order to rectify this situation, O'Brien (1988, Journal of the American Statistical Association 83, 52-61) has proposed two new statistics, the generalized t and generalized rank-sum procedures, which may be much more powerful than their traditional counterparts in such situations. Recently, however, Blair and Morel (1991, Statistics in Medicine in press) have shown that referencing these new statistics to standard F tables as recommended by O'Brien results in inflations of Type I errors. This paper provides tables of critical values which do not produce such inflations. Use of these new critical values results in Type I error rates near nominal levels for the generalized t statistic and slightly conservative rates for the generalized rank-sum test. In addition to the critical values, some new power results are given for the generalized tests.
Analyse Numerique d’un Probleme de Stefan a Deux Phases Par une Methode d’Elements Finis

Our purpose is to solve numerically a two-phase Stefan problem in a bounded open set $\Omega $ of the two-dimensional space. First, we describe briefly the equations and the theoretical method of resolution.The numerical approach, which is expected to follow as well as possible the variations of the free boundary, is based on finite elements of first order; then we describe the different schemes used and the nature of their convergence.Lastly, we discuss two examples for which numerical results have been computed.
Time-domain self-consistent theory of frequency-locking regimes in gyrotrons with low-Q resonators

A time-domain theory of frequency-locking gyrotron oscillators with low-Q resonators has been developed. The presented theory is based on the description of wave propagation by a parabolic equation taking into account the external signal by modification of boundary conditions. We show that the developed model can be effectively used for simulations of both single- and multi-mode operation regimes in gyrotrons driven by an external signal. For the case of low-Q resonators typical for powerful gyrotrons, the external signal can influence the axial field profile inside the interaction space significantly and, correspondingly, the value of the electron orbital efficiency.
Miscellanea. Comparison of case-control to full cohort analyses under model misspecification

We investigate the question of whether or not estimates of relative risk from matched case-control studies well represent the population from which they were drawn. We derive the formula for the asymptotic maximum partial likelihood estimators from nested case-control studies when the Cox proportional hazards model is misspecified and compare these to the corresponding full cohort values under various types of model misspecification, such as covariate omission, mismodelling available measurements and covariates measured with error. We found that lack of covariate information, as in covariate omission and measurement error, cannot per se result in differences in case-control and cohort estimates. Differences can only occur when the covariates used in the presumed model are mismodelled and we find that the magnitude of the misspecification must be unreasonably large in order to produce differences of practical importance.
High electron mobility in heavily doped bases of InP/GaInAs HBTs

The minority carrier electron mobility in the base of InP/GaInAs HBTs was measured as a function of temperature using a new magneto transport method. At room temperature the mobility was found to be as high as 3400 cm/sup 2/ V/sup -1/ sec/sup -1/ at a base doping level of 3.4/spl times/10/sup 19/ cm/sup -3/. The measured mobility was compared with calculations carried out using the dielectric function formalism. The dominant scattering mechanisms are ionized impurity scattering and coupled LO phonon-plasmon scattering. The calculations correctly predict the high temperature mobility. At low temperatures a Monte Carlo analysis must be performed to model the experimental results because the electron distribution is nonthermal. The momentum relaxation rate strongly depends on the electron energy due to the elastic nature of the coupled LO phonon-plasmon scattering at low electron energy.
Informative Estimation and Selection of Correlation Structure for Longitudinal Data

Identifying an informative correlation structure is important in improving estimation efficiency for longitudinal data. We approximate the empirical estimator of the correlation matrix by groups of known basis matrices that represent different correlation structures, and transform the correlation structure selection problem to a covariate selection problem. To address both the complexity and the informativeness of the correlation matrix, we minimize an objective function that consists of two parts: the difference between the empirical information and a model approximation of the correlation matrix, and a penalty that penalizes models with too many basis matrices. The unique feature of the proposed estimation and selection of correlation structure is that it does not require the specification of the likelihood function, and therefore it is applicable for discrete longitudinal data. We carry out the proposed method through a groupwise penalty strategy, which is able to identify more complex structures. The proposed method possesses the oracle property and selects the true correlation structure consistently. In addition, the estimator of the correlation parameters follows a normal distribution asymptotically. Simulation studies and a data example confirm that the proposed method works effectively in estimating and selecting the true structure in finite samples, and it enables improvement in estimation efficiency by selecting the true structures.