Miracle-dz/UniFAR-FTUs huggingface dataset:
Shock wave emergence at the stellar surface and the subsequent gas expansion into a vacuum : the sphericity involvement

A solution is constructed to describe the shock wave passage through the outer envelope of the star and the following stellar matter expansion into a vacuum. The solution takes into account the sphericity of the flow in neighborhood of the stellar surface. Calculations are performed for the case γ=4/3, n=3 (γ is the adiabatic index, and n is the peripheric politropic index). At the stage of the shock wave emergence, the sphericity is shown to affect mostly the spatial distributions of density and pressure by increasing their slopes from the surface to the center of the star
Topology and combinatorics of 'unavoidable complexes'

The partition number $\pi(K)$ of a simplicial complex $K\subset 2^{[m]}$ is the minimum integer $\nu$ such that for each partition $A_1\uplus\ldots\uplus A_\nu = [m]$ of $[m]$ at least one of the sets $A_i$ is in $K$. A complex $K$ is $r$-unavoidable if $\pi(K)\leq r$. We say that a complex $K$ is globally $r$-non-embeddable in $\mathbb{R}^d$ if for each continuous map $f: | K| \rightarrow \mathbb{R}^d$ there exist $r$ vertex disjoint faces $\sigma_1,\ldots, \sigma_r$ of $| K|$ such that $f(\sigma_1)\cap\ldots\cap f(\sigma_r)\neq\emptyset$. Motivated by the problems of Tverberg-Van Kampen-Flores type we prove several results (Theorems 3.6, 3.9, 4.6) which link together the combinatorics and topology of these two classes of complexes. One of our central observations (Theorem 4.6), summarizing and extending results of G. Schild, B. Gr\"{u}nbaum and many others, is that interesting examples of (globally) $r$-non-embeddable complexes can be found among the joins $K = K_1\ast\ldots\ast K_s$ of $r$-unavoidable complexes.
Influence of water saturation on the nonlinear elastic mesoscopic response in Earth materials and the implications to the mechanism of nonlinearity

[1] Much is known empirically about the qualitative and quantitative nonlinear response of rocks. Still, the mechanism of nonlinear response in porous media is only speculation. In this work we illustrate evidence from several types of experiments indicating that fluid plays an important role in the nonlinear response. For instance, measurements at low degrees of water saturation indicate that molecular layers of adsorbed moisture as well as condensation fluids significantly influence the linear and nonlinear response at dynamic strain levels due to the activation of internal molecular forces. In rock, we measure a significant increase in the nonlinear response, especially in the saturation range of 1–20%. This is consistent with observed changes in the linear response, but the extent of the variation is larger in the nonlinear measurements, especially in rocks containing small pore systems. These modifications can be attributed to an increased fluid-solid interaction upon wetting causing the material to expand and to soften. Concurrently, the microscopic and mesoscopic hysteretic entities, which give rise to the macroscopically observed nonlinear response, are activated at saturation-dependent opening and closing pressures. As a consequence of the moisture-induced forces, the fraction of active hysteretic units increases with saturation. The fact that the nonlinear response increases with water saturation, especially in the low saturation range, implies that the presence of moisture plays a major role in the nonlinear mechanism or, more precisely, in the activation of that mechanism.
Torque Regulation Is Influenced by the Nature of the Isometric Contraction

The present study aimed to investigate the effects of a continuous visual feedback and the isometric contraction nature on the complexity and variability of force. Thirteen healthy and young male adults performed three MVCs followed by three submaximal isometric force tasks at a target force of 40% of their MVC for 30 s, as follows: (i) push isometric task with visual feedback (Pvisual); (ii) hold isometric task with visual feedback (Hvisual); (iii) hold isometric task without visual feedback (Hnon-visual). Force complexity was evaluated through sample entropy (SampEn) of the force output. Force variability was analyzed through the coefficient of variation (CV). Results showed that differences were task-related, with Pvisual showing higher complexity (i.e., higher SampEn) and decreased variability (i.e., lower CV) when compared with the remaining tasks. Additionally, no significant differences were found between the two hold isometric force tasks (i.e., no influence of visual feedback). Our results are promising as we showed these two isometric tasks to induce different motor control strategies. Furthermore, we demonstrated that visual feedback’s influence is also dependent on the type of isometric task. These findings should motivate researchers and physiologists to shift training paradigms and incorporate different force control evaluation tasks.
Organic field-effect transistors with reduced contact resistance

In this letter, the authors report a reduction in the contact resistance between pentacene and Au source/drain electrodes of organic field-effect transistors (OFETs). By immersing the Au electrodes in a sulfuric acid and hydrogen peroxide mixture, the injection barrier between the Au electrodes and pentacene was lowered by approximately 0.2eV and the contact resistance significantly decreased. The fabricated bottom-contact OFETs revealed a field-effect mobility of more than 0.66cm2∕Vs at a channel length ranging from 3to30μm, which is comparable to that of top-contact OFETs with a 50μm channel length.
Are compact groups of galaxies physically dense

On a compare les proprietes des groupes compacts catalogues par Hickson (1982), aux resultats de plus de 1000 simulations numeriques. On montre qu'environ la moitie des groupes compacts du catalogue de Hickson ne sont en fait que des alignements dus au hasard
Series expansions from the corner transfer matrix renormalization group method: II. Asymmetry and high-density hard squares

The corner transfer matrix renormalization group method is a method, claimed to be subexponential, for numerically calculating physical quantities of statistical mechanical models. In a previous paper, we extended this method to generate series expansions. Here, we show how to extend both the original and series methods to deal with asymmetry in any model. We discuss the cases of rotational, translational and reflection asymmetry, and give some improvements to the method. This is demonstrated by an application of the method to generate series for the hard square model in the high-density regime, producing 51 terms of the partition function and 48 terms of the order parameter. These series are analysed, producing estimates of the critical point and exponents, and showing the likely presence of a confluent singularity with exponent 17/8 in the order parameter.
A critical appraisal of published values of [Fe/H] for K II-IV stars

'Primary' (Fe/H) averages are presented for 373 evolved K stars of luminosity classes II-IV and (Fe/H) values beween . 9 and +0.21 dex. The data define a 'consensus' zero point with a precision of + or {minus} 0.018 dex and have rms errors per datum which are typically 0.08{minus}0.16 dex. The primary data base makes recalibration possible for the large (Fe/H) catalogs of Hansen and Kjaergaard (1971) and Brown et al. (1989). A set of (Fe/H) standard stars and a new DDO calibration are given which have rms of 0.07 dex or less for the standard star data. For normal K giants, CN-based values of (Fe/H) turn out to be more precise than many high-dispersion results. Some zero-point errors in the latter are also found and new examples of continuum-placement problems appear. Thus high-dispersion results are not invariably superior to photometric metallicities. A review of high-dispersion and related work on supermetallicity in K III-IV star is also given.
The rotating interstellar disc in G35.2-0.74

Maps of NH3 (1,1) and (2,2) inversion line emission from the molecular cloud G35.2N have been made at 40-arcsec resolution with the 100-m Effelsberg telescope and at 7-arcsec resolution with the VLA. The source is revealed as a large rotating disc, viewed edge-on, of diameter 1.8 pc. Near the centre of this outer structure is a more dense coaxial rotating inner disc (diameter ~0.4 pc, thickness ≦0.08 pc) of mass ~150 M⊙. A comparison of the (1,1) and (2,2) emission from the inner disc shows that its average density decreases towards the centre, while its temperature rises from ~25 to >100K. It appears that the inner disc is capable of channelling the bipolar outflow from the central source observed in CO.
Systematic Makings of Early Stage Hydrogeologic Conceptual Models

Techniques to obtain optimal value from existing hydrogeological information are neglected in many ground water contamination studies, resulting in great costs to the public. Data collection and routine interpretations should not be good enough for hydrogeologists, who should be inherently adept at keen early perspectives and applying useful generalizations. Techniques are available to obtain and explain expanded knowledge from piecemeal and imprecise information at the early stages of site studies. Scarcity of precise data should not be a deterrent. This needed mindset should precede the prevailing mindset of initial collection of extensive new data, followed by data interpretation and mathematical modeling. The existing mindset is often guided by rigid regulations.
An affine projection algorithm using grouping selection of input vectors

This paper present an affine projection algorithm (APA) using grouping selection of input vectors. To improve the performance of conventional APA, the proposed algorithm adjusts the number of the input vectors using two procedures: grouping procedure and selection procedure. In grouping procedure, the some input vectors that have overlapping information for update is grouped using normalized inner product. Then, few input vectors that have enough information for for coefficient update is selected using steady-state mean square error (MSE) in selection procedure. Finally, the filter coefficients update using selected input vectors. The experimental results show that the proposed algorithm has small steady-state estimation errors comparing with the existing algorithms.
Plasma Kinetics in Atmospheric Gases

The book Plasma Kinetics in Atmospheric Gases is a worthwhile contribution to the basic phenomena in nitrogen, oxygen and other atmospheric gases. It contains basic introductory chapters on relaxation in translational, rotational (short) and vibrational (extensive) distribution and on the physics of electron excitation and electron distribution functions. In the latter, electron beam excitation (i.e. high electron energies) are included. In the following chapters, much detail follows on spectroscopic constants of various molecules, molecular fragments and ions, on transport coefficients such as diffusion coefficients, relaxation times and rates. The transfer between translational energies and rotational and vibrational energies are treated in this context. Many (electron) excitation rates, electronic lifetimes and rates for chemical reactions for molecules, fragments and ions are given. The background part of the book is completed with an introductory chapter on wall reactions and accommodation coefficients. In this way an enormous wealth of data for nitrogen-, oxygen- and hydrogen-containing molecules can be found in this book. The book continues with the discussion of discharge physics in pure nitrogen and oxygen, and in mixtures. Some examples are given of applications, of which cleaning of atmospheric gases is, in my view, one of the most important. The many processes which play a role in the ionosphere are another important example of the application of the basic material for nitrogen, oxygen and other molecules. The kinetics which play a role in re-entry problems, and which have a limiting effect on the heat flux, are another example of the application of the plasma chemistry of nitrogen and oxygen gases. In this context fits also a short treatment of acoustic and shock waves, with which the book closes. The structure of the book is that of separate chapters which are in a logical order and follow naturally from the preceding ones. The chapters are separate in the sense that there are not many cross-references between them and all contain their own reference lists. Most of the reference lists (but not all) are extensive and contain recent references. A particular value of the book is the coverage of Russian references. However, I missed in several chapters some references as, for example, a recent book by Ricard on a related subject and other publications of, for example, French and Japanese groups which work on N2 and O2 discharges. This means also that some rates are given without mention of the discussion on them. Nevertheless, in my view this is a very useful book and I will use it extensively. The physics and chemistry of nitrogen- and oxygen-containing plasmas present a great challenge, and much is still unknown and not fully understood, in particular also in combination with surface processes. In this research the book will prove to be a valuable contribution. Professor D C Schram Department of Physics, Eindhoven University of Technology, 5600 MB Eindhoven
Adaptive Orthonormal Basis Functions for High Dimensional Metamodeling With Existing Sample Points

High Dimensional Model Representation (HDMR) is a tool for generating an approximation of an input-output model for a multivariate function. It can be used to model a black-box function for metamodel-based optimization. Recently the authors’ team has developed a radial basis function based HDMR (RBF-HDMR) model that can efficiently model a high dimensional black-box function and, moreover, to uncover inner variable structures of the black-box function. This approach, however, requests a complete new, although optimized, set of sample points, as dictated by the methodology, while in engineering design practice one often has many existing sample data. How to utilize the existing data to efficiently construct a HDMR model is the focus of this paper. We first identify the Random-Sampling HDMR (RS-HDMR), which uses orthonormal basis functions as HDMR component functions and existing sample points can be used to calculate the coefficients of the basis functions. One of the important issues related to the RS-HDMR is that in theory the basis functions are obtained based on the continuous integrations related to the orthonormality conditions. In practice, however, the integrations are approximated by Monte Carlo summation and thus the basis functions may not satisfy the orthonormality conditions. In this paper, we propose new and adaptive orthonormal basis functions with respect to a given set of sample points for RS-HDMR approximation. RS-HDMR models are built for different test functions using the standard and new adaptive basis functions for different number of sample points. The relative errors for both models are calculated and compared. The results show that the models that are built using the new basis functions are more accurate.Copyright © 2012 by ASME
Color space choice for nearly reversible image compression

In applications where nearly reversible color image compression is required, the choice of an appropriate color space is a major factor determining the attainable compression ratio. The optimal choice would satisfy the following conditions: (1) Decorrelate the data as much as possible. (2) Minimize the total number of bits in the data path needed for a certain quality level (assuming a truly reversible component compression scheme). (3) Need no calculations with critical accuracy. We compared several known linear color transformations (under the assumption that the original data was represented in RGB) with respect to these conditions. Decorrelation and entropy reduction were calculated. The number of bits required to guarantee a certain quality level measured in (Delta) Lab units was determined. The effects of transformation coefficient quantization were checked. As a result, a simple transformation needing no multipliers at all is proposed.
Comparison of the extent and mass of CME events in the interplanetary medium using IPS and SMEI Thomson scattering observations

The Solar-Terrestrial Environment Laboratory (STELab), Japan, interplanetary scintillation (IPS) g-level and velocity measurements can be used to give the extent of CME disturbances in the interplanetary medium arising from the scattering of the radio waves from distant point-like natural sources through the intervening medium. In addition, white-light Thomson-scattering observations from the Solar Mass Ejection Imager (SMEI) have recorded the inner heliospheric response to several hundred CMEs. The work described here compares and details the difference in three-dimensional (3D) reconstructions for these two data sets for the well-observed 28 October 2003 halo CME seen in LASCO; this passed Earth on 29 October in the SMEI data at the same elongations as IPS g-level observations. The SMEI data analysis employs a 3D tomographic reconstruction technique that obtains perspective views from outward-flowing solar wind as observed from Earth, iteratively fitting a kinematic solar wind density model, and when av.
Structural and magnetic characterisation of the perovskite oxides La0.7Ca0.3−xNaxMnO3

X-ray powder diffraction (XRD) and magnetic measurements were performed in order to investigate the effect of Na+ ion substitution for Ca2+ ions on the crystallographic structure, the character of magnetic ordering, and the effect of transition temperature in La0.7Ca0. 3−xNaxMnO3 manganites series (0 ⩽ × ⩽ 0.2). All samples crystallise in an orthorhombic structure with the Pnma space group. We have found a strong dependence of structural and magnetic properties on the cation-size disorder parameter σ2. The temperature dependence of magnetization of all samples obeys the Bloch T3/2 law. The values of the spin wave constant at low temperature B increase with the increase of x and the Curie temperature decreases. It is concluded that the substitution of Ca by Na+ ions causes a decrease in total exchange integral Aof the samples.
Image Definition Identification Algorithm Based on Lifting Wavelet Transform and Naive Bayes Classifier

Identification of definition for digital image is an important aspect of digital imaging system. To improve the efficiency of the present image definition identification methods with a high accuracy, an algorithm based on the compound model of Lifting Wavelet Transform and Naive Bayes classifier is proposed. Firstly, the two-dimensional Lifting Wavelet Transform is used to extract the image feature, and 28 statistical values obtained from 7 wavelet components by statistical process are treated as image eigenvalues for the follow-up identification. Then Naive Bayes classifier is used to achieve the identification, which has a high computational efficiency and competitive accuracy, and the classifier applied to the experiments of this paper is from OpenCV. The experiment consists of two phases. In phase one, the compound model is trained by 200 images from the training set. Similarly, in phase two, the model is tested by 100 images from the testing set. The results show that the algorithm based on the compound model is very effective, and obtains a high recognition rate.
Spread of a heated plane turbulent jet

A heated two‐dimensional turbulent jet flow has been studied experimentally using conditional sampling techniques. The aim of the investigation was to establish the details of the spread of the temperature and velocity fields. Results confirmed previous observations showing that the conventionally measured mean temperature profile was wider than the velocity. However, when considered in terms of the turbulent fluid only, the spread of thermal and of momentum fields was found to be coincident.
PERFORMANCE MANAGEMENT IN POLICE ORGANIZATIONS1

The central purpose of this study is to examine the implementation of a popular performance based management model known as Compstat in large police organization called Newark Police Department. The main question is if this model has improved the performance of this organization. This model has been implemented by numerous police organizations in the United States over the last decade. Data were collected in this case study through in-depth interviews, observation of the Compstat meetings and analysis of the documents, and analyzed using grounded theory. The study revealed that this model certainly improved the performance of the NPD. Accountability and responsibility, flexibility, performance measurement that leads to careerism and competition can be seen as new management values that emerged in Compstat era. Performance orientation became an inevitable part of police management. Two basic mechanisms in Compstat, assessment with tangible indicators and follow up, changed the evaluation of success and failure in the management. The findings suggest designing differently the structure and setting of the Compstat meetings in a way to spur brain storming and promote a learning environment.
Dielectric function of warm dense gold

Single-state measurements of the broadband (450–800nm) dielectric function of gold using a supercontinuum probe are reviewed. These measurements have demonstrated the first evidence of the existence of band structure in ultrathin gold foils isochorically heated by a femtosecond laser pulse to energy densities of 106–107J∕kg. The Drude component of the dielectric function increases with energy density while the interband component shows both enhancement and redshift. Ab initio molecular-dynamics calculations based on thermalized electrons cannot reproduce the experimental results, suggesting a non-Fermi distribution of excited electrons.
Morphogenesis of the gastrovascular canal network in Aurelia jellyfish: Variability and possible mechanisms

Patterns in biology can be considered as predetermined or arising from a self-organizing instability. Variability in the pattern can, thus, be interpreted as a trace of instability, growing out from noise. Studying this variability can, thus, hint toward an underlying morphogenetic mechanism. Here, we present the variability of the gastrovascular system of the jellyfish Aurelia. In this variability emerges a typical biased reconnection between canals and time-correlated reconnections. Both phenomena can be interpreted as traces of mechanistic effects, the swimming contractions on the tissue surrounding the gastrovascular canals, and the mean fluid pressure inside them. This reveals the gastrovascular network as a model system to study the morphogenesis of circulation networks and the morphogenetic mechanisms at play.
A standardized protocol for manually segmenting stroke lesions on high-resolution T1-weighted MR images

Although automated methods for stroke lesion segmentation exist, many researchers still rely on manual segmentation as the gold standard. Our detailed, standardized protocol for stroke lesion tracing on high-resolution 3D T1-weighted (T1w) magnetic resonance imaging (MRI) has been used to trace over 1,300 stroke MRI. In the current study, we describe the protocol, including a step-by-step method utilized for training multiple individuals to trace lesions (“tracers”) in a consistent manner and suggestions for distinguishing between lesioned and non-lesioned areas in stroke brains. Inter-rater and intra-rater reliability were calculated across six tracers trained using our protocol, resulting in an average intraclass correlation of 0.98 and 0.99, respectively, as well as a Dice similarity coefficient of 0.727 and 0.839, respectively. This protocol provides a standardized guideline for researchers performing manual lesion segmentation in stroke T1-weighted MRI, with detailed methods to promote reproducibility in stroke research.