Miracle-dz/UniFAR-FTUs huggingface dataset:
Heat and Momentum Transfers under Strong Stability in the Atmospheric Surface Layer

Abstract Transfers of heat and momentum under strongly stable conditions in the atmospheric boundary layer have been studied through measurements of the turbulent fluctuations and vertical mean profiles of wind velocity and air temperature. As the local gradient Richardson number increases, intermittent turbulence appears, especially in temperature fluctuations. The ratio of the eddy conductivity to the eddy viscosity decreases with increasing Richardson number and tends to zero at high stabilities. The local value of the dimensionless shear function for wind velocity does not exceed a limit of about six. These results imply that the eddy viscosity for very stable conditions does not take the infinitesimally small value predicted from extrapolation of the so-called log-linear profile, and that the flux Richardson number has a limit in the range of 0.1–0.4, although the gradient Richardson number can become indefinitely large. It is also shown that the divergences of both the radiative and turbulent heat f.
Integrated high‐transition temperature magnetometer with only two superconducting layers

We describe the fabrication and testing of an integrated YBa2Cu3O7−x thin‐film magnetometer consisting of a dc superconducting quantum interference device (SQUID), with biepitaxial grain boundary junctions, integrated with a flux transformer on a single substrate. Only two superconducting layers are required, the SQUID body serving as the crossunder that completes the multiturn flux transformer. The highest temperature at which any of the magnetometers functioned was 76 K. At 60 K the magnetic field gain of this device was 63, and the magnetic field noise was 160 fT Hz−1/2 at 2 kHz, increasing to 3.4 pT Hz−1/2 at 1 Hz.
Radio properties of optically discovered quasars

VLA observations to flux density levels below 2 mJy are presented for 69 optically discovered quasars. These results are combined with existing data to consider the radio properties of 228 optically discovered quasars. Nineteen have been detected as radio sources. The differential function Psi(R*), where R* is ratio of radio (5000 MHz) to optical (2500 A) flux density, appears flat for low radio-to-optical ratio. About 2% of all quasars in any bin of width . delta. log R*=0.4 are radio sources. About 12% of all quasars are radio sources at levels above log R*=0.8. There do not appear to be significant differences in absolute luminosity, apparent optical magnitude, or redshift for radio-strong, compared to radio-quiet, quasars.
On Extremal Theory for Stationary Processes

Let $\{\xi(t)\}_{t \geq 0}$ be a stationary stochastic process, with one-dimensional distribution function $G$. We develop a method to determine an asymptotic expression for $\Pr\{\sup_{0 \leq t \leq h} \xi(t) > u\}$, when $u \uparrow \sup\{v: G(v) < 1\}$, applicable when $G$ belongs to a domain of attraction of extremes, and we show that if $G$ belongs to such a domain, then so does the distribution function of $\sup_{0 \leq t \leq h} \xi(t)$. Applications are given to hitting probabilities for small sets for $\mathbb{R}^m$-valued Gaussian processes and to extrema of Rayleigh processes. Further, we prove the Gumbel, Frechet and Weibull laws, for maxima over increasing intervals, when $G$ is type I-, type II- and type III-attracted, respectively, and we establish the asymptotic Poisson character of $\varepsilon$-upcrossings and local $\varepsilon$-maxima.
Terahertz conductivity of the metal-insulator transition in a nanogranular VO2 film

Terahertz time-domain spectroscopy is used to measure the complex terahertz conductivity of a nanogranular vanadium dioxide (VO2) thin film as a function of temperature through the metal-insulator transition. The Drude–Smith model provides a good fit to the observed terahertz conductivity, revealing a metallic state that forms via switching of individual nanograins and strong carrier confinement within the nanograins due to scattering off grain boundaries. Furthermore, the directly applied Drude–Smith model provides a more accurate description of the measured terahertz conductivity in this material than either Bruggeman or Maxwell–Garnett effective medium theories.
SOLITON EIGENFUNCTION EQUATIONS: THE IST INTEGRABILITY AND SOME PROPERTIES

Eigenfunctions of the linear eigenvalue problems for the soliton equations obey nonlinear differential equations. It is shown that these eigenfunction equations are integrable by the inverse spectral transform (IST) method. They have triad operator representations. Eigenfunction equations are the generating equations and possess other interesting properties. Eigenfunction equations form a new wide class of nonlinear integrable equations. Eigenfunction equations for several typical, well-known (1+1)-, (2+1)- and multi-dimensional soliton equations are considered. A general method for constructing the auxiliary linear systems for the eigenfunction equations is proposed. It is shown that the vertical hierarchies of the eigenfunction equations contain only finite numbers of different members in the cases considered. The properties of such hierarchies for soliton equations are closely connected with their Painleve properties. Some “linear” properties of the eigenfunction equations are also discussed.
Versions of Kernel-Type Regression Estimators

Abstract We explore the aims of, and relationships between, various kernel-type regression estimators. To do so, we identify two general types of (direct) kernel estimators differing in their treatment of the nuisance density function associated with regressor variable design. We look at the well-known Gasser-Muller, Nadaraya-Watson, and Priestley-Chao methods in this light. In the random design case, none of these methods is totally adequate, and we mention a novel (direct) kernel method with appropriate properties. Disadvantages of even the latter idea are remedied by kernel-weighted local linear fitting, a well-known technique that is currently enjoying renewed popularity. We see how to fit this approach into our general framework, and hence form a unified understanding of how these kernel-type smoothers interrelate. Though the mission of this article is unificatory (and even pedagogical), the desire for better understanding of superficially different approaches is motivated by the need to improve prac.
Scattering from a layer of discrete random medium over a random interface: application to microwave backscattering from forests

Abstract The distorted Born approximation is used to calculate the bistatic scattering coefficients from a layer of sparsely distributed discrete dielectric scatterers over a random interface. After specializing to the backscatter case, the scattering coefficient is determined as a sum of direct, direct reflected and interface scatter contributions. The direct reflected term contains contributions from the average interface and the interface fluctuations. These direct reflected terms include both incoherent and coherent or enhancement terms. The results are applied to backscattering from a mature hemlock forest over a roughened ground. The model results show that the direct reflected surface fluctuation terms give the dominant contribution to backscatter at P band and are equal in magnitude to the volume scatter at L band. Use of these new results brings the model predictions and experimental results into agreement.
Stabilization of a 2-DOF spherical pendulum on X-Y table

In this paper, a 2-DOF spherical pendulum system is constructed and balanced on a X-Y table. The pendulum is projected onto the x-z and y-z planes, which are parallel to the two motion directions of the X-Y table. These projections are treated independently to each other and are controlled separately. The stabilization control for a 1D inverted pendulum is proposed based on the state space approach and the Lie theoretic tools without resorting any direct approximation to each nonlinear term. A specially developed sensor system allows the contactless measurement of the inclination angles of the pendulum. The experimental results are reported.
X-Ray Luminosity Functions of Normal Galaxies in the Great Observatories Origins Deep Survey

We present soft (0.5-2 keV) X-ray luminosity functions (XLFs) in the Great Observatories Origins Deep Survey (GOODS) fields derived for galaxies at z ~ 0.25 and 0.75. SED fitting was used to estimate photometric redshifts and separate galaxy types, resulting in a sample of 40 early-type galaxies and 46 late-type galaxies. We estimate k-corrections for both the X-ray/optical and X-ray/NIR flux ratios, which facilitates the separation of AGNs from the normal/starburst galaxies. We fit the XLFs with a power-law model using both traditional and Markov-Chain Monte Carlo (MCMC) procedures. A key advantage of the MCMC approach is that it explicitly takes into account upper limits and allows errors on "derived" quantities, such as luminosity densities, to be computed directly (i.e., without potentially questionable assumptions concerning the propagation of errors). The slopes of the early-type galaxy XLFs tend to be slightly flatter than the late-type galaxy XLFs, although the effect is significant at only the 90% and 97% levels for z ~ 0.25 and 0.75. The XLFs differ between z < 0.5 and z > 0.5 at >99% significance levels for early-type, late-type, and all (early- and late-type) galaxies. We also fit Schechter and lognormal models to the XLFs, fitting the low- and high-redshift XLFs for a given sample simultaneously assuming only pure luminosity evolution. In the case of lognormal fits, the results of MCMC fitting of the local FIR luminosity function were used as priors for the faint- and bright-end slopes (similar to "fixing" these parameters at the FIR values, except here the FIR uncertainty is included). The best-fit values of the change in log L* with redshift were Δ log L* = 0.23 ± 0.16 dex (for early-type galaxies) and 0.34 ± 0.12 dex (for late-type galaxies), corresponding to (1 + z)1.6 and (1 + z)2.3. These results were insensitive to whether the Schechter or lognormal function was adopted.
Laser irradiation of carbon nanotube films: Effects and heat dissipation probed by Raman spectroscopy

We investigate the thermal properties of thin films formed by single- and multi-walled carbon nanotubes submitted to laser irradiation using Raman scattering as a probe of both the tube morphology and the local temperature. The nanotubes were submitted to heating/cooling cycles attaining high laser intensities (∼1.4 MW/cm2) under vacuum and in the presence of an atmosphere, with and without oxygen. We investigate the heat diffusion of the irradiated nanotubes to their surroundings and the effect of laser annealing on their properties. The presence of oxygen during laser irradiation gives rise to an irreversible increase of the Raman efficiency of the carbon nanotubes and to a remarkable increase of the thermal conductivity of multi-walled films. The second effect can be applied to design thermal conductive channels in devices based on carbon nanotube films using laser beams.
E1 transitions of astrophysical interest in neutral oxygen

Atomic transition rates and f values have been calculated in the triplet and quintet systems and for some intercombination lines of neutral oxygen. Configuration interaction was included in the calculations performed with the CIV3 code of Hibbert (1975) for all the transitions connecting the n=3 and n=4 energy levels. In order to reproduce the observed energy splittings between the energy states, small empirical adjustments were introduced to the diagonal matrix elements. Comparisons with previously published f values and radiative lifetimes are discussed and the subsequent astrophysical applications of the results are briefly mentioned.
Coordination control of multiple Euler–Lagrange systems for escorting mission

In this paper, a motion control problem of multi‐agent systems for escorting a target is investigated by employing nonsingular fast terminal sliding mode control and adaptive control associated with kinematic control. The proposed control law is robust to model uncertainty and disturbances, and it guarantees all the agents to scatter around the target evenly and escort it with a fixed distance while avoiding obstacles (or collisions) in p‐dimensional case ( p≥2 is a positive integer). Finite‐time convergence of the position errors and velocity errors is proved rigorously by a Lyapunov‐based approach and finite‐time control techniques. Simulation results in both two‐dimensional and three‐dimensional space are provided to illustrate the effectiveness and high‐precision performance of the control algorithm compared with the traditional adaptive sliding mode control, showing that all the agents can move into suitable positions on the surface of the sphere in the escort mission, and the formation can be reconfigured automatically when the obstacle (or collision) avoidance task is active. Copyright © 2014 John Wiley & Sons, Ltd.
The HCO+ Molecular Outflow in NGC 2071

We present high angular resolution and multitransition HCO+ observations toward the NGC 2071 molecular outflow. Comparison of the high-velocity (HV) HCO+ and the near-IR H2 in the molecular outflow shows a clear correlation. At high HCO+ flow velocities the spatial coincidence is especially remarkable. In addition, the HV HCO+ presents clear morphological and kinematical differences with the CO outflow. These differences appear not only in the HV HCO+ emission associated with the H2 but in the overall outflow. There is a clear HCO+ emission enhancement, relative to CO, at increasing flow velocities. This enhancement is probably due to an abundance enhancement produced by a velocity-dependent chemistry in the shocks. An overabundance of CH in low Mach shocks may cause the HCO+ abundance enhancement. Because of the short cooling time for H2, the correlation between the HCO+ and the H2 implies that HCO+ emission can provide a useful tool to study in detail the current interactions of protostellar winds with the dense ambient medium. At the position of the extremely high velocity (EHV) CO component in the red lobe we detect HCO+ (J = 3 → 2) emission within the velocity range of the EHV CO gas. This emission is roughly compatible with the expected HCO+ emission associated with EHV gas arising from behind dissociative shocks.
Market Transparency, Relational Contracts and Collusion in the Colombian Electricity Market

In models of collusive behaviour firms deviate from current profit maximization in anticipation of future rewards. As current profit maximization places little restrictions on firms’ pricing behaviour, these models are hard to test and collusive conduct hard to infer from pricing behaviour alone. This paper tests for, and quantifies the value of, a collusive arrangement in the Colombia energy sector. We take advantage of the announcement of a market transparency reform that potentially made it harder for firms to sustain a collusive arrangement. We show that bids submitted by a subset of firms in the market collapsed immediately after the announcement, and before the implementation of the reform. We construct several proxies for (potential) cartel membership based on firms’ characteristics a priori correlated with incentives and ability to collude. Within an event-study framework, the resulting proxies capture well the observed drop in bids following the announcement. We rule out confounders and provide forensic evidence of how the cartel functioned and how firms might have communicated about it. A calibration of the dynamic incentives compatibility constraints confirms that a collusive arrangement was sustainable before, but not after, the reform. Profits of firms’ in the cartel and the equilibrium price fell substantially after the reform. A back-of-the-envelope calculation suggests that the average consumer paid 3% higher energy bills as a result of the cartel.
CHARACTERIZATION OF QUASI-DISKS AND TEICHMÜLLER SPACES

if it is the image of the unitdisk by a quasiconformal automorphism of the sphere. Since Ahlfors'investigation [2] in 1963, several characteristic properties of quasi-diskshave been studied by many authors. As a result, quasi-disks are relatedto various topics in analysis. A bird's eye view of these studies aregiven in Gehring [9]. Among them, the topics with which we are con-cerned in this article are the BMO
Electrodynamics of high- T c superconductors

Recent studies of the electromagnetic response of high-Tc superconductors using terahertz, infrared, and optical spectroscopies are reviewed. In combination these experimental techniques provide a comprehensive picture of the low-energy excitations and charge dynamics in this class of materials. These results are discussed with an emphasis on conceptual issues, including evolution of the electronic spectral weight in doped Mott-Hubbard insulators, the d-wave superconducting energy gap and the normal-state pseudogap, anisotropic superfluid response, electronic phase segregation, emergence of coherent electronic state as a function of both temperature and doping, the vortex state, and the energetics of the superconducting transition. Because the theoretical understanding of these issues is still evolving the review is focused on the analysis of the universal trends that are emerging out of a large body of work carried on by many research teams. Where possible data generated by infrared/optical techniques are compared with the data from other spectroscopic and transport methods.
Multilevel adaptive thresholding and shrinkage technique for denoising using Daubechies complex wavelet transform

Abstract In this paper, we have proposed a multilevel soft thresholding technique for noise removal in Daubechies complex wavelet transform domain. Two useful properties of Daubechies complex wavelet transform, approximate shift invariance and strong edge representation, have been explored. Most of the uncorrelated noise gets removed by shrinking complex wavelet coefficients at the lowest level, while correlated noise gets removed by only a fraction at lower levels, so we used multilevel thresholding and shrinkage on complex wavelet coefficients. The proposed method firstly detects strong edges using imaginary components of complex coefficients and then applies multilevel thresholding and shrinkage on complex wavelet coefficients in the wavelet domain at non-edge points. The proposed threshold depends on the variance of wavelet coefficients, the mean and the median of absolute wavelet coefficients at a particular level. Dependence of these parameters makes this method adaptive in nature. Results obtained for one-dimensional signals and two-dimensional images demonstrate an improved denoising performance over other related methods available in the literature.
Sensitivity to tab disturbance of the mean flow structure of nonswirling jet and swirling jet in crossflow

Sensitivity to tab disturbance of the mean flow structure of nonswirling jet in crossflow (JICF) and swirling jet in crossflow (SJICF) is investigated. For the swirling jet, the nonzero tangential velocity, nonzero circulation jet configuration is employed. The configuration allows for the development of the skewed mixing layer at each lateral edge of the jet not to be obscured and modulated by the jet cross-stream boundary layer and the associated vorticity of the opposite sign to that of the imposed swirl. In the investigation, a heated jet is used and the temperature distributions in the cross planes downstream of the jets are surveyed upto x∕rd=1, where r is the effective velocity ratio and d is the diameter of the jet exit. A single stationary tab is alternately placed at eight different azimuthal positions along the periphery of the jet exit. For both JICF and SJICF, the results show that the mean flow structure is most sensitive to tab disturbance in the region centered on the pressure-windward to .
Simulation-based optimization for surgery appointment scheduling of multiple operating rooms

This study is devoted to the appointment scheduling (AS) for a sequence of surgeries with random durations served by multiple operating rooms (Multi-OR). Surgeries are assigned to ORs dynamically on a first-come, first-serve (FCFS) basis. It materially differs from past literature in the sense that dynamic assignments are proactively anticipated in the determination of appointment times. A discrete-event framework is proposed to model the execution of the surgery schedule and to evaluate the sample path gradient of a total cost incurred by surgeon waiting, OR idling, and OR overtime. The sample path cost function is shown to be unimodal, Lipchitz-continuous, and differentiable w.p.1 and the expected cost function continuously differentiable. A stochastic approximation algorithm based on unbiased gradient estimators is proposed and extensive numerical experiments suggest that it converges to a global optimum. A series of numerical experiments is performed to show the significant benefits of the Multi-OR setting and properties of the optimal solution with respect to various system parameters such as cost structure and numbers of surgeries and ORs.
Dynamics of charged particles in bifurcated current sheets: The κ ≈ 1 regime

[1] We examine the nonlinear dynamics of charged particles in the double-hump current sheets that develop during the late growth phase of substorms. We focus on particles for which the adiabaticity parameter κ (defined as the square root of the minimum curvature radius to maximum Larmor radius ratio) is of the order of unity. We show that as in the case of a simple parabolic field reversal, the magnetic moment scattering experienced by these particles may be described as the result of perturbation of the gyromotion by an impulsive centrifugal force. Here however the double-hump structure of the current sheet leads to two successive centrifugal perturbations, which has a significant impact on the net change of magnetic moment. In a single-hump current sheet, three distinct regimes of magnetic moment variations are obtained for a given value of κ, namely, systematic enhancement at small pitch angles, negligible change at large pitch angles, and in between either damping or enhancement depending upon gyration phase. In contrast, in a double-hump current sheet, repeated application of this three-branch pattern can lead to magnetic moment damping for particles that previously experience magnetic moment enhancement and vice versa. The gyrophase gain both during and between the centrifugal impulses is found to play an essential role in the net magnetic moment change. In particular, in contrast to single-hump current sheets, the κ ≈ 1 limit may be characterized by quasi-adiabatic behavior with negligible variations of the magnetic moment.
Analytical Threshold Voltage Formula Including Narrow-Channel Effects for VLSI Mesa-Isolated Fully Depleted Ultrathin Silicon-On-Insulator N-Channel Metal-Oxide-Silicon Devices

We report an analytical threshold voltage formula taking into consideration narrow-channel effects for mesa-isolated fully depleted ultrathin silicon-on-insulator (SOI) n-channel metal-oxide-silicon (NMOS) devices based on a quasi-two-dimensional approach. From the analytical formula, contrary to LOCOS-isolated bulk NMOS devices, the narrow-channel effects in the mesa-isolated fully depleted ultrathin SOI NMOS devices are due to elevation of the electrostatic potential in the conducting channel near the sidewall.