Miracle-dz/UniFAR-FTUs huggingface dataset:
Perturbation of initial and boundary conditions for a limited‐area ensemble: multi‐model versus single‐model approach

With the aim of developing of an ensemble forecasting system for the short‐range, the validity of a multi‐analysis multi‐model approach for initial‐ and boundary‐condition perturbations has been explored by the Consortium for Small‐scale Modelling (COSMO). This approach has been adopted in the COSMO Short‐Range Ensemble Prediction System (COSMO–SREPS), in which members are driven by a few operational deterministic runs. In this work, we show the extent to which this approach is beneficial with respect to the downscaling of a single‐model global ensemble, adopted by the operational COSMO Limited‐Area Ensemble Prediction System (COSMO–LEPS). Both COSMO–SREPS and COSMO–LEPS are made up of 16 integrations of the COSMO model with 7 km horizontal mesh size. Results based on the 2010–2011 winter season show that the 16 member COSMO–LEPS outperforms the 16 member COSMO–SREPS, which has boundaries perturbed by three global model runs only, but the reverse is true when the three‐member versions of the two systems are compared. Hence, if only a small‐size Limited‐Area Model (LAM) ensemble is feasible, then the multimodel approach for boundaries gives better results. The dependence of the scores on ensemble size is also studied, showing that all the quality measures tend to saturate before the full size is reached. Finally, the impact of combining the two ensembles is assessed, showing that a positive impact results from adding multi‐model‐driven members to COSMO–LEPS.
Two-step triangular-pattern phase-shifting method for three-dimensional object-shape measurement

Existing phase-shifting measurement methods involve processing of three acquired images or computation of functions that require more complex processing than linear functions. This paper presents a novel two-step triangular-pattern phase-shifting method of 3-D object-shape measurement that combines advantages of earlier techniques. The method requires only two image-acquisition steps to capture two images, and involves projecting linear grayscale-intensity triangular patterns that require simpler computation of the intensity ratio than methods that use sinusoidal patterns. A triangular intensity-ratio distribution is computed from two captured phase-shifted triangular-pattern images. An intensity ratio-to-height conversion algorithm, based on traditional phase-to-height conversion in the sinusoidal-pattern phase-shifting method, is used to reconstruct the object 3-D surface geometry. A smaller pitch of the triangular pattern resulted in higher measurement accuracy; however, an optimal pitch was found, below which intensity-ratio unwrapping failure may occur. Measurement error varied cyclically with depth and may partly be due to projector gamma nonlinearity and image defocus. The use of only two linear triangular patterns in the proposed method has the advantage of less processing than current methods that process three images, or methods that process more complex functions than the intensity ratio. This would be useful for high speed or real-time 3-D object-shape measurement.
On Low-rank Trace Regression under General Sampling Distribution

A growing number of modern statistical learning problems involve estimating a large number of parameters from a (smaller) number of noisy observations. In a subset of these problems (matrix completion, matrix compressed sensing, and multi-task learning) the unknown parameters form a high-dimensional matrix B*, and two popular approaches for the estimation are convex relaxation of rank-penalized regression or non-convex optimization. It is also known that these estimators satisfy near optimal error bounds under assumptions on rank, coherence, or spikiness of the unknown matrix. In this paper, we introduce a unifying technique for analyzing all of these problems via both estimators that leads to short proofs for the existing results as well as new results. Specifically, first we introduce a general notion of spikiness for B* and consider a general family of estimators and prove non-asymptotic error bounds for the their estimation error. Our approach relies on a generic recipe to prove restricted strong convexity for the sampling operator of the trace regression. Second, and most notably, we prove similar error bounds when the regularization parameter is chosen via K-fold cross-validation. This result is significant in that existing theory on cross-validated estimators do not apply to our setting since our estimators are not known to satisfy their required notion of stability. Third, we study applications of our general results to four subproblems of (1) matrix completion, (2) multi-task learning, (3) compressed sensing with Gaussian ensembles, and (4) compressed sensing with factored measurements. For (1), (3), and (4) we recover matching error bounds as those found in the literature, and for (2) we obtain (to the best of our knowledge) the first such error bound. We also demonstrate how our frameworks applies to the exact recovery problem in (3) and (4).
Real-Parameter Evolutionary Monte Carlo With Applications to Bayesian Mixture Models

We propose an evolutionary Monte Carlo algorithm to sample from a target distribution with real-valued parameters. The attractive features of the algorithm include the ability to learn from the samples obtained in previous steps and the ability to improve the mixing of a system by sampling along a temperature ladder. The effectiveness of the algorithm is examined through three multimodal examples and Bayesian neural networks. The numerical results confirm that the real-coded evolutionary algorithm is a promising general approach for simulation and optimization.
The physical properties of early-type massive stars

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Measurements of melting layer attenuation at X‐band frequencies

The attenuation at X band caused by the melting layer of stratiform precipitation is derived by comparing long‐term average reflectivity profiles from collocated X‐band and UHF vertically pointing radars. The total attenuation caused by the bright band is equivalent to the attenuation across approximately 10 km of rain that is present below it. This bright band attenuation is still 3–5 times the “rain equivalent” attenuation, the latter being obtained by integrating the specific attenuation deduced from the entire reflectivity profile across the bright band as if the reflectivity were due to rain. This suggests that in most stratiform rain cases, the total attenuation due to the melting layer exceeds that of the rain below it.
Dwarf galaxy candidates found on the SERC EJ sky survey

We inspected a sky region with declination range of [ 0°, -18°] based on the SERC EJ plate copies. As a result a list of 50 nearby dwarf galaxy candidates with angular diameters is presented. Most of the galaxies have low and very low surface brightness. More than 60% of the objects are detected for the first time.
Relevant Cues for the Visual Perception of Depth: Is Where You See it Where it is?

We tested seven visual depth cues (relative brightness, relative size, relative height, linear perspective, foreshortening, texture gradient, and stereopsis) at viewing distances of one and two meters to answer two questions. First, which cues provide effective depth information (i.e., only a small change in the depth cue results in a noticeable change in perceived depth). Second, how does the effectiveness of these depth cues change as a function of the viewing distance? Six college-aged subjects were tested with each depth cue at both viewing distances. They were tested using a method of constant stimuli procedure and a modified Wheatstone stereoscopic display. Accuracies for perceptual match settings for all cues were very high (mean constant errors were near zero), and no cues were significantly more or less accurate than any others. Effectiveness of the perspective cues (linear perspective, foreshortening, and texture gradient) was superior to that of other depth cues, while effectiveness of relative brightness was vastly inferior. Moreover, stereopsis, among the more effective cues at one meter, was significantly less so at two meters. These results have theoretical implications for models of human spatial perception and practical implications for the design and development of 3D virtual environments.
Applications of advanced metrology techniques for the characterization of extreme ultraviolet mask blank defects

Abstract. Characterization of defects and their sources is essential for developing mitigation solutions to support the production of defect-free extreme ultraviolet (EUV) mask blanks. The characterization of sub-100-nm defects pose challenges to the conventional metrology techniques, such as atomic force microscopy and scanning electron microscopy, limiting mitigation of nanoscale defects. SEMATECH’s Mask Blank Development Center houses advanced metrology capabilities that include transmission electron microscopy (TEM) and Auger electron spectroscopy (AES) to address these shortcomings. Scanning TEM was used to study the disruption of the Mo/Si multilayer of phase defects and to perform elemental analysis with energy dispersive x-ray spectroscopy that has supported projects including substrate smoothing activities, deposition simulation development, and defect printability studies. The Auger instrument was used to create elemental maps for defect identification and to characterize the ion beam deposition tool. Using advanced metrology, mitigation of small defects is being realized, yielding mask blanks with defect counts as low as eight defects at 50-nm sensitivity (Lasertec M7360 SiO2 sphere equivalent) measured over the quality area of 132×132 mm2. The issues with the metrology of increasingly small EUV mask blank defects will be outlined, and comprehensive defect characterization results using TEM and AES will be presented.
Nonparametric Bayes Estimators Based on Beta Processes in Models for Life History Data

The article studies the problem of finding Bayes estimators for cumulative hazard rates and related quantities, w.r. t. prior distributions that correspond to cumulative hazard rate processes with nonnegative independent increments. A particular class of prior processes, termed beta processes, is introduced and is shown to constitute a conjugate class. An important bonus of the approach based on cumulative hazards is that more complicated models for life history data than the simple life table situation can be treated, for example, time-inhomogeneous Markov chains. We find posterior distributions and derive Bayes estimators in such models and present a semiparametric Bayesian analysis of the Cox regression model
Higher Spin Holography

This dissertation splits into two distinct halves. The first half is devoted to the study of the holography of higher spin gauge theory in AdS3. We present a conjecture that the holographic dual of WN minimal model in a ’t Hooft-like large N limit is an unusual “semilocal” higher spin gauge theory on AdS3×S. At each point on the S lives a copy of three-dimensional Vasiliev theory, that contains an infinite tower of higher spin gauge fields coupled to a single massive complex scalar propagating in AdS3. The Vasiliev theories at different points on the S are correlated only through the AdS3 boundary conditions on the massive scalars. All but one single tower of higher spin symmetries are broken by the boundary conditions. This conjecture is checked by comparing tree-level twoand threepoint functions, and also one-loop partition functions on both side of the duality. The second half focuses on the holography of higher spin gauge theory in AdS4. We demonstrate that a supersymmetric and parity violating version of Vasiliev’s higher spin gauge theory in AdS4 admits boundary conditions that preserve N = 0, 1, 2, 3, 4 or 6 supersymmetries. In particular, we argue that the Vasiliev theory with U(M) Chan-Paton and N = 6 boundary condition is holographically dual to the 2+1 dimensional U(N)k × U(M)−k ABJ theory in the limit of large N, k and finite M . In this system all bulk higher spin fields transform in the adjoint of the U(M) gauge group, whose bulk t’Hooft coupling is MN . Our picture
Consolidation of Native Species Aquaculture in Southeastern Mexico: Continuation of a Selective Breeding Program for Native Cichlids and Snook Aquaculture

One of the most important fisheries resources of Mexico is the snook group. Its economic importance is so big that this group of fish is considered among the most precious organisms for coastal and inland fishermen. This pressure over the resource has generated a high exploitation resulting in capture decreasing, especially for large organismsmainly composed of adult females. Within most of the countries of the range of the snooks, the issue is the same. As a result, researchers from United States, Central America and Brasil have demonstrated their concern to develop actions that ensure the continuity of the management of this resource (Tucker y Campbell, 1988; Taylor et al., 1998; Álvarez-Lajonchere et al., 2002; Cerqueira y Tsuzuki, 2009). In the US, especially in Florida and Texas, sport fishing constitutes a very important economic industry and there have been isolated efforts for artificially reproducing these specie for restocking (Tucker y Campbell, 1988; McMichael et al., 1989; Taylor et al., 1998; Neidig et al., 1999; Skapura et al., 1999 and Main et al., 2009).
Frequency-time distribution of a spontaneous photon emitted by two level atom in one-dimensional damped nanocavity with a single resonance mode

The nonperturbative theory of the cooperative spontaneous emission from a two level atom trapped in one-dimensional damped nanocavity with a single resonance mode is presented. The time-dependent spectral properties and nonlinear dynamics of a separate photon emission by the macroolecular-like system "excited atom coupled to a resonance decaying mode" have been analyzed. The investigation has been carried out by solving the Schrödinger equation in the interaction picture with the help of the Green functions method in the Heitler-Ma's form . The formalism was supplemented with the novel algorithm in operating causal singular functions and with fundamentals of the theory of quantum quasi-stationary systems. The proposed theory accounts automatically of both reabsorptions of emitted photon and its simultaneous escaping out of the cavity. Solutions of the wave equation were found without using intermediate virtual states and series expansions. In accordance with the theory of quasistationary systems the field of mode decaying exponentially in the empty nanocavity was represented with the Lorenz-shaped packet of stationary photonic states (quasi-modes). The electro-dipolar interaction between the atom and the mode field was adopted to be switched on suddenly. The expressions and plots of emission spectral densities probabilities together with photon emission probability dynamics as functions of time for various ratios Γ/4g. For Γ/4g<1 the transient emission spectrum reveals the presence of two symmetrical side-bands and the central peak interconnected with each other in the area of interaction with the atom. Since the central component oscillates, decaying simultaneously in time at two rates infinity Γ/2 and ~ Γ/4, in the area of interaction the emission is a triplet with satellites oscillating in the interaction area and being stable outside of it. So the final spectrum is a doublet outside of nanocavity. On the contrary for Γ/4g ≥1 the spectrum is a singlet, and the emission occurs in exponentially decaying way.
Physics considerations for laser-plasma linear colliders

Physics considerations for a next-generation linear collider based on laser-plasma accelerators are discussed. The ultrahigh accelerating gradient of a laser-plasma accelerator and short laser coupling distance between accelerator stages allows for a compact linac. Two regimes of laser-plasma acceleration are discussed. The highly nonlinear regime has the advantages of higher accelerating fields and uniform focusing forces, whereas the quasilinear regime has the advantage of symmetric accelerating properties for electrons and positrons. Scaling of various accelerator and collider parameters with respect to plasma density and laser wavelength are derived. Reduction of beamstrahlung effects implies the use of ultrashort bunches of moderate charge. The total linac length scales inversely with the square root of the plasma density, whereas the total power scales proportional to the square root of the density. A 1 TeV center-ofmass collider based on stages using a plasma density of 10 17 cm � 3 requires tens of J of laser energy per stage (using 1 � m wavelength lasers) with tens of kHz repetition rate. Coulomb scattering and synchrotron radiation are examined and found not to significantly degrade beam quality. A photon collider based on laser-plasma accelerated beams is also considered. The requirements for the scattering laser energy are comparable to those of a single laser-plasma accelerator stage.
Preparing Secondary Mathematics Teachers: A Focus on Modeling in Algebra

This study addressed the opportunities to learn (OTL) modeling in algebra provided to secondary mathematics pre-service teachers (PSTs). To investigate these OTL, we interviewed five instructors of required mathematics and mathematics education courses that had the potential to include opportunities for PSTs to learn algebra at three universities. We also interviewed a group of three to four PSTs at each of the universities. We coded the interview transcripts using an analytic framework developed based on related literature and policy documents. We report the similarities and differences in perspectives among instructors and PSTs related to modeling at each university, along with comparisons of OTL across universities.
Equatorial Zonal Wind in the Middle Atmosphere Derived from Geopotential Height and Temperature Data

Abstract This paper examines the feasibility of deriving the zonal wind at the equator using monthly mean temperature and geopotential height data from satellite and radiosonde/rocketsonde measurements. Using climatological data of the stratosphere and mesosphere based on monthly mean Nimbus 5 Selective Chopper Radiometer and Nimbus 6 Pressure Modulator Radiometer measurements, and stratospheric monthly mean data from the National Meteorological Center for 1979–86, we present meridional cross sections and time profiles of the zonal wind in the tropical middle atmosphere. The derived zonal wind at the equator reproduces the mean climatology of the tropical middle atmosphere as well as the general characteristics of the equatorial quasi-biennial (QBO) and semiannual oscillations (SAO) observed in monthly mean radiosonde and rocketsonde data. Although the amplitude of the derived wind QBO is for the most part underestimated relative to direct wind measurements, the amplitude of the derived wind SAO compares .
Thermodynamic functions of fluctuating electromagnetic fields within a heterogeneous system

Thermodynamic functions of the equilibrium fluctuating electromagnetic fields within a nonuniform dispersive and absorptive system are calculated and discussed. The near-interface subsystem of the fields deserves special attention. Density of states and spectral characteristics of thermal surface waves in equilibrium at the interface between two media, one of them being lossy, are calculated for the first time. Thermodynamic characteristics of thermal fields are calculated both in vacuum and inside bulk lossy material described by spatially local and nonlocal optical responses. It was shown that the higher the temperature of the system, the smaller the relative contribution of the evanescent part of thermodynamic functions of thermal fields in vacuum compared with those of the black-body radiation. It is suggested that the evanescent part of the thermally excited fields can be treated as the physical transition layer localized near the interface between two subsystems of photons in vacuum and photons in bulk matter. In fact, such a layer forms a physical boundary between those subsystems of thermal photons in equilibrium.
Safety, Strength, Simplicity

When the evidence leaves us with a choice among hypotheses of unequal strength, how is the choice to be made? Caution would counsel us to choose the weakest, the hypothesis that asserts the least, since it is the least likely to fail us later. But the principle of maximum safety quickly reduces to absurdity; for it always dictates the choice of a hypothesis that does not go beyond the evidence at all.
Characterizations of Lie derivations of factor von Neumann algebras

Let ℛ be a factor von Neumann algebra with dimension > 4. In this article, we prove that if δ : ℛ → ℛ is a linear map satisfying for any x, y ∈ ℛ with xy = 0 (resp., xy = p, where p is a fixed nontrivial projection of ℛ), then δ = d + τ, where d is a derivation of ℛ and τ : ℛ → 𝒞I (where 𝒞 is the field of complex numbers) is a linear map vanishing at commutators [x, y] with xy = 0 (resp., xy = p).
M51: molecular spiral arms, giant molecular associations, and superclouds

An aperture synthesis image of the prototypical grand-design spiral galaxy M51 in the CO 1 to 0 line made with the Owens Valley Millimeter Interferometer is presented. The image is a mosaic of 30 1-arcmin fields. Narrow (10-20 arcsec) spiral arms are seen which are coincident with the optical dust lanes and nonthermal radio emission, but are offset from the ridges of H-alpha and thermal radio emission. There are many dense concentrations of emission, termed giant molecular associations (GMAs), both along and between the arms. The GMAs have masses of 10 million to 60 million solar masses, and most of the on-arm ones appear to be bound. They consist of several spectral components, termed molecular superclouds, which also appear to be bound. The interarm GMAs are unbound and are probably due to a secondary compression of the density wave. Streaming motions in the GMAs are consistent with density wave theory. 20 refs.
ESTIMATING RELIABILITY FOR TESTS COMPOSED OF ITEM SETS

To what extent, if any, are estimates of reliability for a multiple choice test affected by the presence of large item sets where each set shares common reading material? The purpose of this research was to assess the effect of local item dependence on estimates of reliability for verbal portions of the old and new SAT, where the new test contains larger item sets associated with reading passages. Estimates based on a single administration of the test (estimates based on internal consistency and estimates based on covariances among parts) were compared to estimates based on two administrations of the test. When adjusted for a fixed standard deviation, estimates based on covariances among parts tended to be similar to estimates based on parallel forms. Both types of estimates were lower than the internal consistency estimates.