Miracle-dz/UniFAR-FTUs huggingface dataset:
Distribution-Free Methods of Estimating Location Difference with Censored Paired Data

Abstract Nonparametric point and interval estimators of location difference in matched pairs data with arbitrary right censorship are proposed, based on a generalized Gehan—Gilbert test (Wei 1980). The point estimator is shown to be asymptotically normal and strongly consistent. The limits of the corresponding interval estimator are readily computable. An example is also provided to illustrate the techniques to problems in survival data analysis.
Twelve-year trail of clues leads to impact crater from the K-T boundary

The search started with a hypothesis that was literally out of this world: Could a massive comet or asteroid, perhaps 10 km in diameter, have struck the Earth about 65 million years ago, changing the climate so drastically that the dinosaurs and other creatures could no longer survive? That question was raised in 1980 by Luis Alvarez, his son Walter, Frank Asaro and Helen Michel of the University of California, Berkeley. Their evidence at the time was scanty: only an anomalous concentration of iridium at the geological stratum corresponding to the era when the giant reptiles became extinct and supposedly delivered by the extraterrestrial projectile. (See the article by Luis Alvarez in PHYSICS TODAY, July 1987, page 24.) But the suggestion triggered a massive hunt, and geological sleuths soon gathered much substantiating evidence. The telltale crater, however, remained elusive.
The free-free absorption coefficient of the negative nitrogen ion

A multichannel theory of free-free transitions of an electron in the presence of a general atomic system is employed to evaluate the continuous absorption coefficient for the negative nitrogen ion. The calculation is evaluated over a wide range of radiation wavelengths lambda (AA)=3037-151 890 and temperatures T(K)=1800-10 080. Comparison with previous calculations shows significant differences.
Power flow response based dynamic topology optimization of bi-material plate Structures

Work on dynamic topology optimization of engineering structures for vibration suppression has mainly addressed the maximization of eigenfrequencies and gaps between consecutive eigenfrequencies of free vibration, minimization of the dynamic compliance subject to forced vibration, and minimization of the structural frequency response. A dynamic topology optimization method of bi-material plate structures is presented based on power flow analysis. Topology optimization problems formulated directly with the design objective of minimizing the power flow response are dealt with. In comparison to the displacement or velocity response, the power flow response takes not only the amplitude of force and velocity into account, but also the phase relationship of the two vector quantities. The complex expression of power flow response is derived based on time-harmonic external mechanical loading and Rayleigh damping. The mathematical formulation of topology optimization is established based on power flow response and bi-material solid isotropic material with penalization(SIMP) model. Computational optimization procedure is developed by using adjoint design sensitivity analysis and the method of moving asymptotes(MMA). Several numerical examples are presented for bi-material plate structures with different loading frequencies, which verify the feasibility and effectiveness of this method. Additionally, optimum results between topological design of minimum power flow response and minimum dynamic compliance are compared, showing that the present method has strong adaptability for structural dynamic topology optimization problems. The proposed research provides a more accurate and effective approach for dynamic topology optimization of vibrating structures.
X‐ray optics and monochromators for synchrotron radiation

Techniques of focusing and monochromating the x radiation from a synchrotron source will be discussed. Phase‐space techniques, widely used in charged‐particle beam transport, will be applied to describe the source and optical elements ni the focusing systems. The properties of focusing and nonfocusing x‐ray optics will be presented with emphasis on the advantages of each.
Flux corrected remapping using piecewise parabolic reconstruction for 2D cell‐centered ALE methods

A novel conservative interpolation (remapping) method, in the Arbitrary Lagrangian–Eulerian context for numerical solution of Euler equations on unstructured polygonal grids, is presented. Combination of a piecewise quadratic reconstruction and a flux corrected remapping approach provides a simple, symmetry‐preserving and bounds‐preserving method. The positivity of density and specific internal energy is guaranteed. The complete description of the method and both cyclic remapping and full hydrodynamic 2D numerical examples are given. Copyright © 2014 John Wiley & Sons, Ltd.
Spectrum-Roentgen-Gamma astrophysical mission

The Spectrum-RG (SRG) mission, to be launched in 2011, will conduct the first all-sky survey in the 0.1-15 keV band via two imaging telescope systems, eROSITA and ART-XC. These will enable the detection of about 100 thousand clusters of galaxies and the mapping of the large scale structure of the Universe. They will also discover all obscured accreting Black Holes in nearby galaxies and about ≥3 million new, distant AGNs. In the course of the survey mode two sky regions around the celestial polar zones will be observed with much higher sensitivity. Then, selected sources and dedicated sky regions will be observed in a pointing mode with high sensitivity in order to investigate the nature of dark matter and dark energy. An X-Ray Calorimeter, the SXC experiment, will permit observations of the brightest clusters of galaxies with record energy resolution in pointing mode and mapping of the hot intergalactic medium in the survey mode.
Active Steering Assistance for Lane Keeping and Lane Departure Prevention

Single-vehicle road departure accidents represent a substantial amount of today’s accidents. This paper presents the design and experimental test of an active steering assistance system that offers two functions: lane departure avoidance by temporary activation and maintaining vehicle heading by permanent activation. Each of the two functions can be used exclusively or in combination. Specific constraints related to each of the two functions are taken into account in the control design of the steering assistance by using LMI (linear matrix inequality) and BMI (bilinear matrix inequality) optimization methods. Consequently, lane overshoot is minimized for assistance activations near the border of the lane even during curve negotiation and robust lane keeping is ensured. Furthermore, the effects on lane keeping performance of simultaneous steering by the driver and the assistance are theoretically quantified. The results are verified using a fully equipped prototype vehicle. The obtained field test is consistent with the expected performance.
Gallic Acid-Loaded Sodium Alginate-Based (Polyvinyl Alcohol-Co-Acrylic Acid) Hydrogel Membranes for Cutaneous Wound Healing: Synthesis and Characterization

Traditional wound dressings often cannot treat wounds caused by bacterial infections or other wound types that are insensitive to these wound treatments. Therefore, a biodegradable, bioactive hydrogel wound dressing could be an effective alternative option. The purpose of this study was to develop a hydrogel membrane comprised of sodium alginate, polyvinyl alcohol, acrylic acid, and gallic acid for treating skin wounds. The newly developed membranes were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), sol-gel fraction, porosity, mechanical strength, swelling, drug release and data modelling, polymeric network parameters, biodegradation, and antioxidation (DPPH and ABTS) and antimicrobial activity against Gram-positive and negative bacteria. The results revealed that hydrogel membranes were crosslinked successfully and had excellent thermal stability, high drug loading, greater mechanical strength, and exhibited excellent biodegradation. Additionally, the swelling ability and the porosity of the surface facilitated a controlled release of the encapsulated drug (gallic acid), with 70.34% release observed at pH 1.2, 70.10% at pH 5.5 (normal skin pH), and 86.24% at pH 7.4 (wounds pH) in 48 h. The gallic acid-loaded hydrogel membranes showed a greater area of inhibition against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli bacteria as well as demonstrated excellent antioxidant properties. Based on Franz cell analyses, the permeation flux of the drug from optimized formulations through mice skin was 92 (pH 5.5) and 110 (pH 7.4) μg/cm2·h−1. Moreover, hydrogel membranes retained significant amounts of drug in the skin for 24 h, such as 2371 (pH 5.5) and 3300 µg/cm2 (pH 7.4). Acute dermal irritation tests in rats showed that hydrogel membranes were nonirritating. Hydrogel membranes containing gallic acid could be an effective option for improving wound healing and could result in faster wound healing.
Self-Assessment and Learning Motivation in the Second Victim Phenomenon

Introduction: The experience of a second victim phenomenon after an event plays a significant role in health care providers’ well-being. Untreated; it may lead to severe harm to victims and their families; other patients; hospitals; and society due to impairment or even loss of highly specialised employees. In order to manage the phenomenon, lifelong learning is inevitable but depends on learning motivation to attend training. This motivation may be impaired by overconfidence effects (e.g., over-placement and overestimation) that may suggest no demand for education. The aim of this study was to examine the interdependency of learning motivation and overconfidence concerning second victim effects. Methods: We assessed 176 physicians about overconfidence and learning motivation combined with a knowledge test. The nationwide online study took place in early 2022 and addressed about 3000 German physicians of internal medicine. Statistics included analytical and qualitative methods. Results: Of 176 participants, 83 completed the assessment. Analysis showed the presence of two overconfidence effects and in-group biases (clinical tribalism). None of the effects correlated directly with learning motivation, but cluster analysis revealed three different learning types: highly motivated, competent, and confident “experts”, motivated and overconfident “recruitables”, and unmotivated and overconfident “unawares”. Qualitative analysis revealed four main themes: “environmental factors”, “emotionality”, “violence and death”, and “missing qualifications” contributing to the phenomenon. Discussion: We confirmed the presence of overconfidence in second victim management competencies in about 3% of all persons addressed. Further, we could detect the same three learning motivation patterns compared to preceding studies on learning motivation in other medical competencies like life support and infection control. These findings considering overconfidence effects may be helpful for safety managers, medical teachers, curriculum developers and supervisors to create preventive educational curricula on second victim recognition and management.
Automatic Generation of Seepage Flow Nets by Finite Element Method

An analytical method for automatically generating a seepage flow net using the finite element method (FEM) is described. This technique includes a new, more analytical (as compared with numerical) approach to determining the boundary conditions for computing the stream function and a refined approach to handling the transition between multiple layers. Equipotentials are obtained by contouring the results of the FEM solution where total head at each node is computed. The boundary conditions are then modified using the Cauchy‐Riemann equations governing conjugate harmonic functions, and a second FEM problem is solved to compute stream function at each node. Appropriately contouring these results produces the desired flow lines, and the flow net is complete. Procedures for confined flow, unconfined flow, and multilayer systems are presented with examples. A discussion for axisymmetric problems is also given.
Automated image mosaicking

Abstract This paper developed and implemented automated image mosaicking procedures to produce seamless and smooth mosaics from random sequences of digital aerial images and satellite images. The procedure employs automated algorithms for global image registration, seam line extraction, radiometric adjustment, and composition of overlap images. Results of the experimentation on mosaicking black and white orthorectified aerial images and on mosaicking multi‐resolution color infrared SPOT‐2 and Landsat‐5 satellite images show that the implementation of automated conjugate point extraction and image matching algorithms automates the establishment of geometric registration among overlapped images, while the seam line selection and two‐step lookup table histogram matching approaches facilitate creating globally smooth and qualitative mosaics. The system developed in this paper makes complex composition of multi‐source multi‐resolution multi‐band images with different geometric and radiometric characteristics an easy and efficient solution for producing reliable mosaic images.
Feature extraction of kernel regress reconstruction for fault diagnosis based on self-organizing manifold learning

The feature space extracted from vibration signals with various faults is often nonlinear and of high dimension. Currently, nonlinear dimensionality reduction methods are available for extracting low-dimensional embeddings, such as manifold learning. However, these methods are all based on manual intervention, which have some shortages in stability, and suppressing the disturbance noise. To extract features automatically, a manifold learning method with self-organization mapping is introduced for the first time. Under the non-uniform sample distribution reconstructed by the phase space, the expectation maximization(EM) iteration algorithm is used to divide the local neighborhoods adaptively without manual intervention. After that, the local tangent space alignment(LTSA) algorithm is adopted to compress the high-dimensional phase space into a more truthful low-dimensional representation. Finally, the signal is reconstructed by the kernel regression. Several typical states include the Lorenz system, engine fault with piston pin defect, and bearing fault with outer-race defect are analyzed. Compared with the LTSA and continuous wavelet transform, the results show that the background noise can be fully restrained and the entire periodic repetition of impact components is well separated and identified. A new way to automatically and precisely extract the impulsive components from mechanical signals is proposed.
On the asymptotic performance of median smoothers in image analysis and nonparametric regression

For d-dimensional images and regression functions the true object is estimated by median smoothing. The mean square error of the median smoother is calculated using the framework of M-estimation, and an expression for the asymptotic rate of convergence of the mean square error is given. It is shown that the median smoother performs asymptotically as well as the local mean. The optimal window size and the bandwidth of the median smoother are given in terms of the sample size and the dimension of the problem. The rate of convergence is found to decrease as the dimension increases, and its functional dependence on the dimension changes when the dimension reaches 4.
The shifted 1/N expansion and the energy eigenvalues of the Hulthen potential for l not= 0

The shifted 1/N expansion has been used to obtain the energy values of the Hulthen potential for non-zero values of the orbital angular momentum. The analytic expression for the energies En,l yield fairly accurate results for a wide range of values of n,l and the screening parameter lambda . The energy values obtained by this method have been compared and found to be in excellent agreement with Pade approximation calculations.
Chemomechanical surface patterning and functionalization of silicon surfaces using an atomic force microscope

Surface modification and patterning at the nanoscale is a frontier in science with significant possible applications in biomedical technology and nanoelectronics. Here we show that an atomic force microscope (AFM) can be employed to simultaneously pattern and functionalize hydrogen-terminated silicon (111) surfaces. The AFM probe was used to break Si–H and Si–Si bonds in the presence of reactive molecules, which covalently bonded to the scribed Si surface. Functionalized patches and patterned lines of molecules were produced. Linewidths down to 30 nm were made by varying the force at the tip.
Some Methods of Constructing Generalized Group Divisible Designs with Two Groups

ABSTRACT In this article some simple and general methods for constructing, binary and nonbinary, generalized group divisible designs with two groups (GGDD(2)) are given. Near resolvable balanced incomplete block designs and certain classes of balanced incomplete block designs play key roles in the construction of these designs. All the constructed designs are found to be E-optimal.
Accurate efficiency evaluation of energy-transfer processes in phosphosilicate Er3+-Yb3+-codoped fibers

A new approach for the prediction of energy-transfer efficiencies in codoped Er-Yb double-clad fiber (EYDCF) is presented. Ab initio calculations have been performed on the basis of migration-assisted energy-transfer models. The two main Yb energy-transfer parameter that is needed in all modelings based on rate equations can be calculated by use of a simple relation. Our approach also permits the prediction of the laser efficiency of EYDCFs, and a comparison of measured and calculated maximum laser slope efficiency shows a good agreement.
Reducing the critical current for spin-transfer switching of perpendicularly magnetized nanomagnets

We describe nanopillar spin valves with perpendicular anisotropy designed to reduce the critical current needed for spin transfer magnetization reversal while maintaining thermal stability. By adjusting the perpendicular anisotropy and volume of the free element consisting of a [Co/Ni] multilayer, we observe that the critical current scales with the height of the anisotropy energy barrier and we achieve critical currents as low as 120 μA in quasistatic room-temperature measurements of a 45 nm diameter device. The field-current phase diagram of such a device is presented.
Interpolation of wind, temperature and humidity values from model levels to the height of measurement

A new analytical technique is proposed to interpolate data between the lowest model level and the earth's surface in numerical weather prediction systems. The data can be interpolated to any height and especially to the one of routine measurements. The method can therefore be applied either to the verification of forecasts or to the determination of “observation minus guess” increments in data assimilation. The procedure assumes that a Monin-Obukhov-type flux calculation has been previously performed when integrating the model. DOI: 10.1111/j.1600-0870.1988. tb00352.x
Estimation in compositional data analysis

Compositional data arise naturally in several branches of science, including chemistry, geology, biology, medicine, ecology and manufacturing design. In chemistry, these constrained data seem to occur typically when raw data are normalized or when output is obtained from a constrained estimation procedure, such as might be used in a source apportionment problem. It is important not only for chemists to be aware that the usual multivariate statistical techniques are not applicable to constrained data, but also to have access to appropriate techniques as they become available. The currently available methodology is due principally to Aitchison and is based on log–normal models. This paper suggests new parametric and non‐parametric approaches to significantly improve the existing methodology. In the parametric setting, some recent work of Rayens and Srinivasan is extended and a practical regression model is proposed. In the development of the non‐parametric approach, minimum distance methods coupled with multivariate bootstrap techniques are used to obtain point and region estimators.
Atmospheric laser radar as an undergraduate educational experience

The Georgia Tech Research Institute has teamed with a local undergraduate women’s institution, Agnes Scott College, to develop an eye safe atmospheric laser radar (lidar) system as a research experience for undergraduates. The students constructed the lidar under the supervision of Georgia Tech researchers after attending lectures and doing laboratory work on the technologies required to design and build the system. The course succeeded in making lidar technology accessible and appropriate for undergraduates and as a model for other schools. The associated research projects include studies of the planetary boundary layer, tropospheric aerosols and clouds, and the stratospheric aerosol layer.
Bayesian adaptive B-spline estimation in proportional hazards frailty models

Frailty models derived from the proportional hazards regression model are frequently used to analyze clustered right-censored survival data. We propose a semiparametric Bayesian methodology for this purpose, modeling both the unknown baseline hazard and density of the random effects using mixtures of B-splines. The posterior distributions for all regression coefficients and spline parameters are obtained using Markov Chain Monte Carlo (MCMC). The methodology permits the use of weighted mixtures of parametric and nonparametric components in modeling the hazard function and frailty distribution; in addition, the spline knots may also be selected adaptively using reversible-jumpMCMC. Simulations indicate that the method produces smooth and accurate posterior hazard and frailty density estimates. The Bayesian approach not only produces point estimators that outperform existing approaches in certain circumstances, but also offers a wealth of information about the parameters of interest in the form of MCMC samples from the joint posterior probability distribution. We illustrate the adaptability of the method with data from a study of congestive heart failure.
A simplified trace formula for Hecke operators for Γ

Let N and n be relatively prime positive integers, let χ be a Dirichlet character modulo N, and let k be a positive integer. Denote by S k (N,χ) the space of cusp forms on Γ 0 (N) of weight k and character χ, a space denoted simply S k (N) when χ is the trivial character. Beginning with Hijikata's formula for the trace of T n acting on S k (N, χ), we develop a formula which essentially reduces the computation of this trace to looking up values in a table. From this formula we develop very simple formulas for (1) the dimension of S k (N, χ) and (2) the trace of T n acting S k (N)
Explicit level‐set‐based topology optimization using an exact Heaviside function and consistent sensitivity analysis

This paper presents a level‐set‐based topology optimization method based on numerically consistent sensitivity analysis. The proposed method uses a direct steepest‐descent update of the design variables in a level‐set method; the level‐set nodal values. An exact Heaviside formulation is used to relate the level‐set function to element densities. The level‐set function is not required to be a signed‐distance function, and reinitialization is not necessary. Using this approach, level‐set‐based topology optimization problems can be solved consistently and multiple constraints treated simultaneously.