Miracle-dz/UniFAR-FTUs huggingface dataset:
Robust Estimation of State Occupancy Probabilities for Interval-Censored Multistate Data: An Application Involving Spondylitis in Psoriatic Arthritis

We formulate a three-state illness-death model to estimate the proportion of psoriatic arthritis patients developing spondylitis over time. Data from a longitudinal cohort of patients are available but the transitions in this model are interval-censored for the onset of spondylitis; times of deaths are right-censored. Robust methods for estimating the prevalence of spondylitis over time are described based on differences in marginal survivor functions for state entry times in the spirit of Pepe et al. (1991). Nonparametric estimates (Turnbull, 1976) and local likelihood estimates (Loader, 1999) of the marginal distributions are derived. Multiplicative intensity Markov regression models are used to examine covariate effects.
Effects of morphology and strain on the dielectric response of multiferroic CoFe2O4–BaTiO3 nanocomposite thin films

The dielectric response (permittivity and losses) of epitaxial CoFe2O4–BaTiO3 thin film nanocomposites deposited under different conditions has been measured. Exhaustive microstructural analyses have allowed tracking the evolution of structure and morphology as a function of thickness, deposition temperature and rate. It is found that the dielectric permittivity of the nanocomposite increases with the grain size of the BaTiO3 matrix and when reducing its unit cell volume, while losses are quite insensitive to changes in morphology and crystal structure of the ferroelectric phase. We analyze the consequences of these results in view of the functional optimization of nanocomposites.
Nonlinear Flight Control Design Using Constrained Adaptive Backstepping

The design of an adaptive backstepping flight control law for the F-16/MATV (multi-axis thrust vectoring) aircraft is discussed. The control law tracks reference trajectories with the angle of attack a, the stability-axes roll rate p s , and the total velocity V T . Furthermore, the sideslip angle β has to be kept at zero. B-spline neural networks are used inside the parameter update laws of the backstepping control law to approximate the uncertain aerodynamic forces and moments. Command filters are used to implement the constraints on the control surfaces and the virtual control states. The stability of the parameter estimation process during periods of saturation is guaranteed by using a modified tracking error definition, in which the effect of the saturation has been filtered out. The controller and its performance are evaluated on a nonlinear, six-degrees-of-freedom dynamic model of an F-16/MATV aircraft in a number of simulation scenarios.
PriorBand: HyperBand + Human Expert Knowledge

Hyperparameters of Deep Learning (DL) pipelines are crucial for their performance. While a large number of methods for hyperparameter optimization (HPO) have been developed, they are misaligned with the desiderata of a modern DL researcher. Since often only a few trials are possible in the development of new DL methods, manual experimentation is still the most prevalent approach to set hyperparameters, relying on the researcher’s intuition and cheap preliminary explorations. To resolve this shortcoming of HPO for DL, we propose PriorBand , an HPO algorithm tailored to DL, able to utilize both expert beliefs and cheap proxy tasks. Empirically, we demonstrate the efficiency of PriorBand across a range of DL models and tasks using as little as the cost of 10 training runs and show its robustness against poor expert beliefs and misleading proxy tasks.
Chaotic behavior of the piccolo

A direct numerical solution of the Navier-Stokes equations has been used to calculate the sound produced by a model of the piccolo. At low to moderate blowing speeds and at appropriate blowing angles, the sound pressure is approximately periodic with the expected frequency. As the blowing speed is increased or as the blowing angle is varied, the time dependence of the sound pressure becomes more complicated, and examination of the spectrum and the sensitivity of the sound pressure to initial conditions suggest that the behavior becomes chaotic. Similarities with the behavior found in Taylor-Couette and Rayleigh-Benard instabilities of fluids are noted and possible implications for the nature of the piccolo tone are discussed.
Transient evolution regimes in a multiscale dynamo model: Timescales of the reversal mechanism

[1] In order to better understand the origin and nature of reversals of the Earth's magnetic field, we examine the reversal mechanism of a multiscale dynamo model. This model can be described as a cellular automaton with long-range interaction. Different states correspond to different types of helical motions, and a hierarchical structure of length scales is used to mimic helicity transfers in fully developed turbulence. These multiscale helical motions and a differential rotation are the ingredients of a schematic αω dynamo. The model exhibits rich behavior, including long periods of stable magnetic polarity (i.e., chrons), sudden reversals, excursions, and secular variation. Three transient regimes of evolution emerge: (1) Chrons are initiated by an amplification mechanism, which involves spontaneous reorientation of large length scale circulation and an α-quenching mechanism reinforcing the asymmetry of flow during runaway growth in magnetic field intensity. (2) During the chrons the injection of turbulence at small length scale slowly restores the symmetry of the system and leads to reversal. (3) During reversals the magnetic field does not remember its previous polarity, its intensity collapses, and spontaneous reorientation of large length scale circulation is more likely to occur (see regime 1). Reversal duration therefore corresponds to an upper value of the time constants for underlying turbulence in the absence of a magnetic field. We observe a constant excursion rate during chrons and a power law relationship between the reversal rate and the magnitude of helical forcing until a limit for dynamo action is reached. Extrapolated to the Earth's dipole field, this model predicts the duration of both chrons and reversals and sheds light on physical processes that may be responsible for their systematic occurrence.
A Broad-Range Tailored Test of Verbal Ability

Two parallel forms of a broad-range tailored test of verbal ability have been built. The test is appro priate from fifth grade through graduate school. Simulated test administrations indicate that the 25- item tailored test is at least as good as a compar able 50-item conventional test. At most ability levels, the tailored test measures much better. An offer is made to provide upon request item charac teristic curve parameters for 690 widely used Coop erative Test items, in order to facilitate research.
Model Fokker—Planck Equations: Part 3. Application to transport phenomena

The Chapman—Enskog expansion is applied to the model Fokker—Planck equation for a plasma, derived in part 2. It is shown that the complete set of transport coefficients can be calculated without further approximations. Results are derived first in the absence of any external magnetic field. The transport coefficients are also derived when there is a strong magnetic field, in which case they become anisotropic.
On the topological cyclic homology of the integers

This article provides a computation of the mod p homotopy groups of the fixed points of the Topological Hochschild Homology of the ring of integers under the action of any finite subgroup of the cirle group whose order is a power of an odd prime p. This leads to a computation of the Topological Cyclic Homology groups of the ring of integers, and determines also the /7-adic completion of the algebraic AT-theory of the p-adic integers. 1. Introduction. The topological Hochschild homology J ////(/_) is a spec trum (or infinite loop space) associated functorially to each algebraic ring R, or, more generally, to each strictly associative ring spectrum Tl. It was introduced originally by Bokstedt in (B). The spectrum THH(R) comes equipped with a natural action of the circle group T. The topological cyclic homology of R, TC(R) is the homotopy inverse limit of a diagram of spectra with vertices the fixed point spectra THH(R)C of THH(R) under the action of the finite cyclic subgroups C of the circle. The maps in this diagram are either inclusions of fixed points or certain "Frobenius" maps particular to the topological Hochschild homology construction (see (G)). The topological Hochschild and cyclic homology of R are both related to the algebraic jT their relation can be depicted by a commutative diagram of spectra
Mass transport in the boundary layer at a free oscillating surface

In a previous paper (1953b) it was shown theoretically that just below the boundary layer at the surface of a free wave the mass-transport gradient should be exactly twice that given by Stokes's irrotational theory. The present paper describes careful experiments which confirm the higher value of the gradient. The results have an implication for any oscillatory boundary layer at the free surface of a fluid; such a boundary layer must generate a second-order mean vorticity which diffuses inwards into the interior of the fluid.
Photoinduced Insulator-to-Metal Transition in a Perovskite Manganite

We have observed an insulator-to-metal (I-M) transition triggered by the photocarrier injection into the charge-ordered (CO) state of a perovskite manganite crystal, Pr{sub 0.7}Ca {sub 0.3}MnO {sub 3}. The photocurrent is a highly nonlinear function of applied electric field and of light intensity; both show a threshold behavior for the I-M transition. The dependence of the anomalous photocurrent on the excitation photon energy and the temperature excludes the laser heating as the cause of the effect, suggesting the photocarrier-mediated collapse of the CO state. {copyright} {ital 1997} {ital The American Physical Society}
Comparison of the photon charge between water and solid phantom depending on depth

Background: This study assessed the clinical usefulness of the solid phantom, which may compensate for the disadvantages of the water phantom, by comparing the radiological doses between the two depending on their depths. Materials and Methods: The experimental equipment used was a linear accelerator for medical use, water phantom, solid phantom, Farmer type ion chamber and electrometer. The distance between the ray source and the center of the ion chamber was fi xed to a SAD of 100 cm during the experiment. The field size was 10 x 10 cm 2 and the radia%on energies of the photon rays were 6 MV and 15 MV. The depth interval was 1cm (range 1-10 cm) for each energy. The rela%ve devia%on ra%o of the water phantom to the solid phantom was calculated. Results: The measurement at 100 MU was performed more than five %mes to calculate the average charge and absorbed dose, and the rela%ve devia%on was analyzed based on the water phantom. The results obtained at depths from 1 to 10 cm were 0.034%, 0.457%, -0.167%, 0.011%, 0.117%, 0.271%, 0.349%, 0.709%, 0.376% and 0.611% at 6 MV and those obtained at 15 MV were 1.199%, 0.033%, 0.166%, 0.496%, 0.556%, 0.705%, 0.656%, 1.071%, 0.7% and 1.057%, respec%vely. Conclusion: In conclusion, the solid phantom is useful and may complement the disadvantages of the water phantom, including the %me required for its installa%on and errors in the measurement depth, and may precisely measure the radiological dose.
Improvements of an ice-phase microphysics parameterization for use in numerical simulations of tropical convection

Abstract It is important to properly simulate the extent and ice water content of tropical anvil clouds in numerical models that explicitly include cloud formation because of the significant effects that these clouds have on the radiation budget. For this reason, a commonly used bulk ice-phase microphysics parameterization was modified to more realistically simulate some of the microphysical processes that occur in tropical anvil clouds. Cloud ice growth by the Bergeron process and the associated formation of snow were revised. The characteristics of graupel were also modified in accord with a previous study. Numerical simulations of a tropical squall line demonstrate that the amount of cloud ice and the extent of anvil clouds are increased to more realistic values by the first two changes.
Was Marx right? or How efficient are laser driven interstellar spacecraft?

The idea of a laser driven space vehicle capable of interinterstellar travel was raised 25 years ago. The original article by Marx [Nature 211, 22–23 (1966)] presented a relativistic calculation that contained conceptual and numerical errors. Here the inconsistencies of the original article are corrected. Marx’s calculations are generalized to the case where the laser is of variable power, and to the interesting case where the laser beam is recycled by means of mirrors. The obstacles to this form of interstellar travel appear insurmountable, but the calculations provide an excellent example of the application of relativistic ideas.
Weighted geometric means of positive operators

A weighted version of the geometric mean of k () positive invertible operators is given. For operators and for nonnegative numbers such that , we define weighted geometric means of two types, the first type by a direct construction through symmetrization procedure, and the second type by an indirect construction through the non-weighted (or uniformly weighted) geometric mean. Both of them reduce to if commute with each other. The first type does not have the property of permutation invariance, but satisfies a weaker one with respect to permutation invariance. The second type has the property of permutation invariance. We also show a reverse inequality for the arithmetic-geometric mean inequality of the weighted version.
Local Spatial Autocorrelation Statistics: Distributional Issues and an Application

The statistics Gi(d) and Gi*(d), introduced in Getis and Ord (1992) for the study of local pattern in spatial data, are extended and their properties further explored. In particular, nonbinary weights are allowed and the statistics are related to Moran's autocorrelation statistic, I. The correlations between nearby values of the statistics are derived and verified by simulation. A Bonferroni criterion is used to approximate significance levels when testing extreme values from the set of statistics. An example of the use of the statistics is given using spatial-temporal data on the AIDS epidemic centering on San Francisco. Results indicate that in recent years the disease is intensifying in the counties surrounding the city.
Dynamic analysis of radial force density in brushless DC motor using 3-D equivalent magnetic circuit network method

The distribution of radial force density in brushless permanent magnet DC motors is not uniform in the axial direction. The analysis of radial force density has to consider the 3-D shape of teeth and overhang, because the radial force density causes vibration and acts on the surface of teeth inconsistently. For the analysis, a new 3-D equivalent magnetic circuit network method is used to account for the rotor movement without remeshing. The radial force density is calculated and analyzed by Maxwell stress tensors and discrete Fourier transforms (DFT) respectively. The results of the 3-D equivalent magnetic circuit method have been compared with the results of 3-D FEM.
Fast Shadowing Technique for Electrically Large Targets Using Z-Buffer

An improved fast shadowing technique fit for the calculation of electromagnetic field is proposed in this paper based on the shadowing technique of z-buffer in computer graphics. The traditional shadowing algorithm consumes too much time, for it is necessary to judge the shadowing relationship of every two facets. The proposed algorithm combining z-buffer with traditional algorithm falls into the shadowing processing using triangle facet modeling. The problem of great time consumption in shadowing judgment for electrically large targets is well solved through proper subdivision of buffer and localization of judgment within facets in the surrounding buffer elements. The proposed arithmetic has great advantages over the traditional one, especially in its high running speed. This improved technique is tested to be valid in that it remarkably increases the computation speed on the premise of satisfying the precision requirement.
Parametric Analysis of Enhanced Heat Transfer for Laminar Flow of Microencapsulated Phase Change Suspension in a Circular Tube with Constant Wall Temperature

A novel phase change microcapsule with compound crust is briefly introduced in this paper, and the heat transfer enhancement due to a microencapsulated phase change material is investigated parametrically for laminar convective heat transfer in a circular tube with constant wall temperature. The size of the phase change mushy region and the phase change interface locations are given for the various governing parameters. Two enhancement ratios, the traditional enhancement ratio and a modified enhancement ratio, were used to quantify the enhanced heat transfer characteristics of the microencapsulated phase change suspension for six major parameters. The six parameters are the bulk Stephan number, the volumetric concentration of the solid-phase, the particle-to-tube radius ratio, the dimensionless initial subcooling, the dimensionless phase change temperature range, and the bulk Reynolds number. The simulations show that the bulk Stephan number and the volumetric concentration are the most important parameters influencing the heat transfer enhancement of the microencapsulated suspension. The influence of the microcapsule diameters on the heat transfer enhancement comes from the microconvection, instead of the latent heat release due to the phase change. In addition, the combined effect of changes in all of these parameters on the heat transfer enhancement was examined.
An accelerated successive substitution algorithm

Three related proposals are made for accelerating the familiar successive substitution procedure for phase equilibrium flash calculations. Basic to the development of the acceleration procedures is the observation that successive substitution can be regarded as a method of steep descent for free energy minimization. Acceleration is obtained by choosing an optimal step length. Results show a significant decrease in the number of iterations required for convergence, even in difficult problems near the mixture critical point. On propose trois methodes pour accelerer le procede iteratif habituel de calcul des equilibres de phase pour la distillation-eclair. Le developpement de ces methodes est base sur l'observation que les iterations peuvent e'tre considerees comme une methode de gradient maximum pour la recherche du minimum d'energie libre. On obtient l'acceleration en choisissant une longueur optimale pour l'increment. Les resultats obtenus indiquent une diminution du nombre d'iterations requis pour atteindre la convergence, me'me pour les problemes les plus delicats au voisinage du point critique du melange.
Evaluation of Features and Classifiers for Classification of Early-stage Breast Cancer

Microwave Imaging (MI) has been extensively investigated for a number of years to develop a technique to detect breast cancer at the earliest stages of development. MI for this application is based on exploiting the dielectric contrast between normal breast tissue and cancerous tissue at microwave frequencies. Recent findings have reported overlapping dielectric properties between malignant and benign tumour tissue. Therefore, differentiating between benign and malignant tumours based on the dielectric properties alone is potentially problematic. Alternative methods for the classification of breast tumours have to be developed to improve the sensitivity and specificity of MI. In this paper, the Radar Target Signatures (RTS) of tumours are used to classify tumours, since the RTS contain valuable information about the shape and surface texture of tumours. The most important characteristics of any classification system are the feature extraction method used, along with the type of classifier itself. In this paper, the performance and robustness of three different feature extraction methods in combination with three classifiers are examined. A database of 352 tumours, comprising tumours of four shapes and sizes is created using Gaussian Random Spheres to evaluate the feature extraction methods. The three feature extraction methods — Principal Component Analysis (PCA), Independent Component Analysis (ICA), and Discrete Wavelet Transform (DWT) — are compared using three classification methods — Linear Discriminant Analysis (LDA), Quadratic Discriminant Analysis (QDA) and Support Vector Machines (SVM). Significantly, the performance of the feature extraction methods is evaluated using tumours in both a dielectrically homogeneous and heterogeneous breast models.
Spatiotemporal dynamics and feedforward control of an infinite-dimensional, time-variant, thermal-coating process

In this contribution, a model for the spatiotemporal dynamics of a thermal-coating process is derived from first principles (the conservation of energy). The model is a dynamical system consisting of a system of hyperbolic, partial differential equations (PDEs), describing the evolution of the temperature distribution of the substrate. By studying the C 0- semigroup generated by the system operator we find that in discrete time the infinite-dimensional plant may conveniently be represented by finite-dimensional operators defined on appropriately chosen Euclidean spaces. This representation provides the basis for numerical efficient solution of several optimal feedforward control problems associated with set point changes and launching of the process. Numerical and experimental studies highlight the value of this approach.
Das statistische Problem der Korrelation als Variations‐ und Eigenwertproblem und sein Zusammenhang mit der Ausgleichsrechnung

Von einem voll befriedigenden Korrelationsmas ist zu verlangen, das es durch sein Verschwinden mit Sicherheit anzeigt, wenn die beiden Veranderlichen unabhangig voneinander sind, und das es anderseits mit Sicherheit den Wert Eins annimmt, wenn zwischen ihnen vollstandige Abhangigkeit besteht. Die Aufgabe, ein solches Korrelationsmas zu gewinnen, fuhrt auf ein Variationsproblem und kann zuruckgefuhrt werden auf die Frage nach dem kleinsten Eigenwert einer homogenen Fredholmschen Integralgleichung. Bei der Untersuchung dieses Variationsproblems wird auch der Zusammenhang mit den bisher ublichen Korrelationsmasen und mit dem Problem der Ausgleichsrechnung ersichtlich.
On the Environments of Tornadic and Nontornadic Mesocyclones

Abstract The authors investigated differences in the environments associated with tornadic and nontornadic mesocyclones are investigated using proximity soundings. Questions about the definition of proximity are raised. As the environments of severe storms with high spatial and temporal resolution are observed, the operational meaning of proximity becomes less clear. Thus the exploration of the proximity dataset is subject to certain caveats that are presented in some detail. Results from this relatively small proximity dataset support a recently developed conceptual model of the development and maintenance of low-level mesocyclones within supercells. Three regimes of low-level mesocyclonic behavior are predicted by the conceptual model: (i) low-level mesocyclones are slow to develop, if at all, (ii) low-level mesocyclones form quickly but are short lived, and (iii) low-level mesocyclones develop slowly but have the potential to persist for hours. The model suggests that a balance is needed between the mi.