Miracle-dz/UniFAR-FTUs huggingface dataset:
Optimization of image interpolation as an inverse problem using the LMMSE algorithm

In this paper, a linear minimum mean square error (LMMSE) solution to the image interpolation problem is presented. The image interpolation problem is treated as an inverse problem considering the mathematical model by which a low resolution image is obtained from a high resolution image. In the suggested LMMSE (optimum) image interpolation algorithm, three main problems are encountered and solved. The autocorrelation matrix of the high resolution image is required prior to the interpolation process. This matrix is approximated from a polynomial based interpolated image and the sensitivity of the LMMSE solution to the estimation of the autocorrelation matrix is studied. Another problem is the noise variance estimation of the low resolution image. The sensitivity of the LMMSE solution to the noise variance estimation is also studied. The third problem is the large dimension matrix inversion process required for evaluating the high resolution image. This problem is solved by approximating the matrix to be inverted by a sparse matrix. Results show that the suggested solution is superior to polynomial based image interpolation algorithms from the mean square error (MSE) point of view. It is also efficient from the computational complexity point of view.
NCAR/CU Surface, Soil, and Vegetation Observations during the International H2O Project 2002 Field Campaign

Abstract The May–June 2002 International H2O Project was held in the U.S. Southern Great Plains to determine ways that moisture data could be collected and utilized in numerical forecast models most effectively. We describe the surface and boundary layer components, and indicate how the data can be acquired. These data document the eddy transport of heat and water vapor from the surface to the atmosphere (in terms of sensible heat flux H and latent heat flux LE), as well as radiative, atmospheric, soil, and vegetative factors that affect it, so that the moisture and heat supply to the atmosphere can be related to surface properties both for observational studies and tests of land surface models. The surface dataset was collected at 10 surface flux towers at locations representing the major types of land cover and extending from southeast Kansas to the Oklahoma Panhandle. At each location, the components of the surface energy budget (H, LE, net radiation, and soil heat flux) are documented each half-hour, .
A unified confidence interval for reliability-related quantities of two-parameter Weibull distribution

Statistical inference methods for the Weibull parameters and their functions usually depend on extensive tables, and hence are rather inconvenient for the practical applications. In this paper, we propose a general method for constructing confidence intervals for the Weibull parameters and their functions, which eliminates the need for the extensive tables. The method is applied to obtain confidence intervals for the scale parameter, the mean-time-to-failure, the percentile function, and the reliability function. Monte-Carlo simulation shows that these intervals possess excellent finite sample properties, having coverage probabilities very close to their nominal levels, irrespective of the sample size and the degree of censorship.
Direct processes in the energy deposition of protons in silicon

The low energy part of proton induced SBD spectra have higher number of counts than expected from p+Si reactions. This is the case for all proton incident angles but the effect increases when approaching grazing angles. The effect is shown to be mainly due to direct ionization (including straggling) by the protons. The energy deposition due to this process is first calculated using the chord length distribution model which assumes a constant LET value for the protons. This model can explain the main features of the spectra for grazing angles. It fails to produce the long tails found in all spectra which are shown to come from straggling. The direct ionization by the protons may cause SEU in devices with low critical charge.
Size effect on the melting temperature of gold particles

Recently, small particles have been shown to exhibit a melting temperature which depends on the particle size. The various possible experimental methods have been compared and measurements of the melting points of small gold particles have been made using a scanning electron-diffraction technique. This method was applied to particles having diameters down to 20 \AA{}. Consideration of the size distribution over an entire sample makes it necessary to carry out a careful analysis of the experimental results in order to deduce the melting temperature of particles having a well-defined diameter. The experimental results are quantitatively in good agreement with two phenomenological models. The first model describes the equilibrium condition for a system formed by a solid particle, a liquid particle having the same mass, and their saturating vapor phase. The second model assumes the preexistence of a liquid layer surrounding the solid particle and describes the equilibrium of such a system in the presence of the vapor phase. In order to permit a better comparison between both models, a new expression for the thermodynamic equilibrium condition has been derived in the present work. In the case of the first model, the agreement was obtained using only the physical constants of massive gold. In applying the second model, however, one is compelled to assume the existence of a liquid layer having a thickness of about 6 \AA{}.
The Primordial helium abundance from observations of extragalactic H-II regions

The pre-galactic (assumed primordial) helium mass fraction Y p is determined to be 0.228 ± 0.005 (s.e.) or Y p < 0.242 with 95 per cent confidence, taking reasonably likely systematic errors into account. This is based on INT and AAT observations of emission lines from H II galaxies combined with selected data from the literature relating to extragalactic H II regions in general, discussed in a consistent analysis taking into account the known corrections and likely sources of error
Surface plasmon resonance tunability in VO2/Au/VO2 thermochromic structure

Nanometal–VO2 composite systems can exhibit a reversibly tunable localized surface plasmon effect under external temperature stimuli due to the temperature‐sensitive dielectric function of the thermochromic VO2 thin film. In order to improve the tunability range and enhance the resonance shift magnitude (ΔλSPR), the VO2/Au/VO2 sandwich structure was deliberately designed here. The plasmonic and thermochromic characteristics of this structure were powerfully dependent on the gold deposition time (t). By varying this parameter, the resonance wavelength (λSPR) of the semiconductor phase can be regulated from the visible range (686 nm) to the near‐infrared range (1482 nm) and a maximum ΔλSPR of 714 nm can be achieved at t = 3.5 min. This study may provide insights into plasmonic noble metal nanoparticles on a thermochromic VO2 matrix and offer potential applications in temperature‐sensitive nanodevices.
Design challenges and analysis of the ITER core LIDAR Thomson scattering system

The maximum temperature expected in ITER is in the region of 40keV and the minimum average density of approximately 3×1019m−3 is also expected. The proven capability, convenience, and port occupancy of the LIDAR Thomson scattering approach, demonstrated on JET, makes it an excellent candidate for ITER. Nonetheless, there are formidable design challenges in realizing such a diagnostic system. The expected high temperature presents its own problem of a very large relativistic blueshift of the scattered spectrum (e.g., λ∕λ0∼0.35 for Te=40keV), impacting on the laser choice and spectrometer/detector system. The combination of coupling high power lasers to the plasma and broadband wavelength detection has been examined in terms of minimizing the operational risk to the overall system, while optimizing the diagnostic performance. Part of the exercise has also included identifying the present critical components, and reducing their impact, e.g., on diagnostic reliability and performance, and attempt to make the .
How Far behind in Math and Reading Are English Language Learners? Report.

As Congress considers the reauthorization of the No Child Left Behind (NCLB) law, an analysis of recent data from standardized testing around the country shows that the fast growing number of students designated as English language learners (ELL) are among those farthest behind. The analysis of national standardized testing scores shows that about 51% of 8 th grade ELL students are behind whites in reading and math, meaning that the scores for one out of every two will have to improve for the group to achieve parity. In the 4th grade, 35% of ELL students are behind in math and 47% are behind in reading when compared with their white counterparts. The analysis of demographic data shows that important changes in the composition of the limited English speaking population take place between the 4th and 8th grades, which help explain the decline in achievement from elementary to middle school. Many students are moved out of limited English speaking status as they acquire language skills while many newly arrived immigrant children are added to the group. About this report: The achievement analysis is based on the 2005 National Assessment of Educational Progress, also known as the “Nation’s Report Card,” and 35 state-administered assessments mandated by the No Child Left Behind law. The report also uses demographic data, for the nation and for some states, to analyze some of the characteristics of limited English speaking students. About the Pew Hispanic Center: Founded in 2001, the Pew Hispanic Center is a nonpartisan research organization supported by The Pew Charitable Trusts. The Pew Hispanic Center’s mission is to improve understanding of the diverse Hispanic population and to chronicle Latinos' growing impact on the nation. The Pew Hispanic Center is a project of the Pew Research Center, a nonpartisan "fact tank" in Washington, D.C., that provides information on the issues, attitudes, and trends shaping America and the world; it does not advocate for or take positions on policy issues.
On the maximum of a stationary independent increment process

A stationary independent increment process is the continuous time analogue of the discrete random walk, and, as such, has a wide variety of applications. In this paper we consider M(t), the maximum value that such a process attains by time t. By using renewal theoretic methods we obtain results about M(t). In particular we show that if μ, the mean drift of the process, is positive, then M(t)/t converges to μ, and E[M(t + h) – M(t)] → hμ.
Photo-written waveguides in iron-doped lithium niobate crystal employing binary optical masks

Photo-written waveguides employing binary optical masks are investigated in an iron-doped lithium niobate crystal. Planar and Y-branch waveguides are experimentally demonstrated. The index variations along the propagation direction of the writing beam in the crystal are experimentally measured and theoretically analyzed. The influence of the diffraction from the optical masks, which imposes a limitation for the applications of the waveguide fabrication method, is numerically specified. Additionally, the asymmetry of the index distribution in the waveguide region, which is related to the transport process of the photoexcited charge carriers, is revealed and qualitatively explained.
Information Technology and the European Productivity Revival

We analyze the data of 8 European countries using regression and compare the result of our model to Stiroh’s. We find mainly four results as follows. First, different from the result in Stiroh (2002), we found only slightly more than half of the industries’ labor productivity increased around 1993. Second, to some extent, similar to the result in Stiroh (2002), we found it is true that the increase in labor productivity growth was related to ICT in the sense that the most significant increase in labor productivity growth is related to ICT-intensive industries, especially IT producing and FIRE industries. Fourth, the Chow test and chart analysis show that 1993 is not a breakpoint with significant level of 5%.
Free–forced interactions in developing meanders and suppression of free bars

The coexistence of migrating alternate (free) bars, spontaneously developing in erodible channels as a result of an instability process, with steady point bars, forced by curvature in meandering reaches of rivers, is investigated theoretically. A perturbation expansion is set up in terms of two dimensionless small parameters, ε and ν respectively, describing free and forced perturbations. The effect of mixed interactions at O(ν2ε½) is found to be responsible for the damping and slowing down of free bars as channel curvature increases. The theory allows us to determine the threshold value of channel curvature above which free bars are suppressed as a function of meander wavenumber for given flow and sediment characteristics. The minimum channel sinuosity for free bar suppression is found to be associated with the resonant wavenumber range of Blondeaux & Seminara (1985). Theoretical predictions compare satisfactorily with experimental observations by Kinoshita & Miwa (1974). The theory also suggests that free bars may appear again in a more advanced stage of meander development in accordance with field observations by Kinoshita (1961).
Global convergence of a class of trust region algorithms for optimization with simple bounds

This paper extends the known excellent global convergence properties of trust region algorithms for unconstrained optimization to the case where bounds on the variables are present. Weak conditions on the accuracy of the Hessian approximations are considered. It is also shown that, when the strict complementarily condition holds, the proposed algorithms reduce to an unconstrained calculation after finitely many iterations, allowing a fast asymptotic rate of convergence.
Vortical structures in the turbulent boundary layer: a possible route to a universal representation

A study of streamwise oriented vortical structures embedded in turbulent boundary layers is performed by investigating an experimental database acquired by stereoscopic particle image velocimetry (SPIV) in a plane normal both to the mean flow and the wall. The characteristics of the experimental data allow us to focus on the spatial organization within the logarithmic region for Reynolds numbers Reθ up to 15000. On the basis of the now accepted hairpin model, relationships and interaction between streamwise vortices are first investigated via computation of two-point spatial correlations and the use of linear stochastic estimation (LSE). These analyses confirm that the shape of the most probable coherent structures corresponds to an asymmetric one-legged hairpin vortex. Moreover, two regions of different dynamics can be distinguished: the near-wall region below y+=150, densely populated with strongly interacting vortices; and the region above y+=150 where interactions between eddies happen less frequently. Characteristics of the detected eddies, such as probability density functions of their radius and intensity, are then studied. It appears that Reynolds number as well as wall-normal independences of these quantities are achieved when scaling with the local Kolmogorov scales. The most probable size of the detected vortices is found to be about 10 times the Kolmogorov length scale. These results lead us to revisit the equation for the mean square vorticity fluctuations, and to propose a new balance of this equation in the near-wall region. This analysis and the above results allow us to propose a new description of the near-wall region, leading to a new scaling which seems to have a good universality in the Reynolds-number range investigated. The possibility of reaching a universal scaling at high enough Reynolds number, based on the external velocity and the Kolmogorov length scale is suggested.
A Numerical Investigation of the Effect of Electric Charges and Vertical External Electric Fields on the Collision Efficiency of Cloud Drops

Abstract The aerodynamic interaction between electrically charged cloud drops in the presence of vertical external electric fields was numerically investigated for 800 mb and +10°C. The collector drops had radii between 11.4 and 74.3 µm while the collected drops had radii between 1 and 66 µm. The external electric fields considered ranged between 0 and 3429 V cm−1 (=3.429×105V m−1 and the electric charge on the cloud drops ranged between 0 and 1.1×10−4 (=3.7×10−14 C). The results demonstrate that the presence of electric charges and fields of magnitudes observed during thunderstorm and pre-thunderstorm conditions drastically enhance the collision efficiency of cloud drops. The enhancement was found to he most pronounced for the smallest collector drops studied.
Defining work from operational principles

In recent years we have witnessed a concentrated effort to make sense of thermodynamics for small-scale systems. One of the main difficulties is that, at the nano-scale, thermal fluctuations of energy in general render it conceptually difficult to distinguish work from heat. Despite of several attempts to resolve this issue, many of which inspired by quantum information theory, there is still remarkable little consensus on it. In this work, we attempt to define work in a strictly operational way. In our resource-theoretic approach, agents wish to agree upon how much work needs to be invested to effect a transition from one state of an arbitrary quantum work-storage device to another. We introduce basic operational principles, and deduce from them a strict set of mathematical properties that any reasonable function quantifying such work has to fulfil. One of those generalises strong sub-additivity, a key property in quantum information theory, to the domain of thermodynamics. We show that one work quantifier fulfilling all the required properties is the difference of the non-equilibrium free energy of the initial and final state of the work-storage system. More generally, for any work quantifier fulfilling the stated properties, we can derive a quantitative second law in the sense of bounding the work that can be performed using some non-equilibrium resource by the work that is needed to create it. We furthermore discuss the role of path dependence for work quantifiers and the connection to the concept of probability-distributions of work. Our mathematical results can be formulated abstractly and carry over to other resource theories than quantum thermodynamics.
Elf Dosage in Ellipsoidal Models of Man Due to High Voltage Transmission Lines

The fields, flux, and power density produced inside an ellipsoidal model of man by overhead high-voltage transmission lines have been calculated. The values depend strongly on the conductivity and the shape of the ellipsoid and, in general, vary from point to point within it. The maximum energy flux is the more reliable indicator of exposure to the electromagnetic field.
Performance Evaluation of Bidirectional Optical Amplifiers for Amplified Passive Optical Network Based on Broadband Light Source Seeded Optical Sources

We have evaluated the performances of bidirectional optical amplifiers which were suited for the cost-effective implementation of amplified bidirectional passive optical networks (PONs). First, we measured the maximum gains of two simple bidirectional optical amplifiers implemented without using any optical components for the suppression of reflected signals. From the results, the maximum gains of two simple bidirectional amplifiers with a broadband light source (BLS) seeded optical source were limited to be 27 dB due to the reflection-induced in-band crosstalk, when the reflectance coefficients were measured to be -33 dB in both directions. Then, we have also implemented a bidirectional optical amplifier with two band splitters for the amplified bidirectional PON where the two different wavelength bands were allocated to the downstream and upstream signals transmission. In our measurement, we confirmed that the maximum gain of bidirectional optical amplifier with two band splitters could be increased to more than 30 dB owing to the efficient suppression of in-band crosstalk.
PbS nanocrystal solar cells with high efficiency and fill factor

We report on the fabrication of efficient PbS solar cells, showing power conversion efficiencies approaching 4% and fill factors of 60% under AM1.5 illumination. The effect of the size of two different nanocrystals (NCs) on the performance and key parameters of the devices are discussed together with peculiar features of device functioning. The results prove that the devices are not under space-charge limitation and the device performance is influenced by charge trapping which is dependent on the size of the NCs.
The metric entropy of diffeomorphisms Part I: Characterization of measures satisfying Pesin's entropy formula

Soit M une variete de Riemann compacte, soit f:M→M un diffeomorphisme, et soit m une mesure de probabilite de Borel f-invariante sur M. On identifie les mesures pour lesquelles l'inegalite de Margulis et Ruelle qui relie l'entropie aux exposants de Lyapunov atteint l'egalite. On demontre une formule valable pour toutes les mesures invariantes
Self-tuning fuzzy inference based on spline function

Recently, fuzzy systems are used in many fields and places. In order to apply the fuzzy system to wider fields, it is necessary to study the tuning methods of the fuzzy system. Some self-tuning methods were proposed so far. However these conventional self-tuning methods do not have sufficient capability of generalization. In this paper, we propose new self-tuning fuzzy neural networks. The fuzzy neural networks consist of membership functions that are expressed by spline function. Delta rule is applied to tune the membership functions and consequent parts. The effectiveness of the proposed methods is shown by some numerical examples. <<ETX>>
The Path to Predicting Bypass Transition

A theory is presented for calculating the fluctuations in a laminar boundary layer when the free stream is turbulent. The kinetic energy equation for these fluctuations is derived and a new mechanism is revealed for their production. A methodology is presented for solving the equation using standard boundary layer computer codes. Solutions of the equation show that the fluctuations grow at first almost linearly with distance and then more slowly as viscous dissipation becomes important. Comparisons of calculated growth rates and kinetic energy profiles with data show good agreement.In addition, a hypothesis is advanced for the effective forcing frequency and free-stream turbulence level which produce these fluctuations. Finally, a method to calculate the onset of transition is examined and the results compared to data.Copyright © 1996 by ASME
Reliable uncertainty evaluation for ODE parameter estimation – a comparison

The traceability of measurements to SI units requires a traceable calibration of the measurement devices employed. In the calibration for time-dependent measurements the mathematical model typically consists of a system of ODEs with constant parameters. The calibration then requires the estimation of these parameters from measurements of corresponding trajectories, and the assignment of reliable uncertainties to the obtained parameter estimates. Many approaches to parameter estimation in ODEs are available. However, the evaluation of a reliable uncertainty associated with the corresponding parameter estimates is challenging. The reasons are, for instance, the existence of many local minima, numerical instabilities or the non-identifiability of parameters from the available measurement data. Here we discuss some general approaches to ODE parameter estimation and demonstrate practical issues for the example of calibrating force sensors from shock force measurements.