Miracle-dz/UniFAR-FTUs huggingface dataset:
Anisotropic charge transport and contact resistance of 6,13-bis(triisopropylsilylethynyl) pentacene field-effect transistors fabricated by a modified flow-coating method

Using a modified flow-coating method, bottom-gate/bottom-contact type organic field-effect transistors (OFETs) with a highly oriented active layer of 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) were fabricated. The flow-coated TIPS-pentacene films were fairly uniform and consisted of arrays of needle-shaped crystals along the flow-coating direction. The uniformity allowed us to determine the contact resistance by a transfer line method. The usefulness of the modified flow-coating method for fabricating high performance OFETs has been demonstrated, and we found that not only the field-effect mobility but also the contact resistance significantly depends on the channel current direction with respect to the flow-coating direction.
Cyanoacetylene in dense interstellar clouds.

Statistical equilibrium calculations were performed and matched to the observations of several sources. These calculations indicate the following: homogeneous cloud models are inadequate for at least one source, Sgr B2, for which a two-component (core-halo) model is presented; the observed lines of HC/sub 3/N are usually, if not always, optically thin; fairly high densities (> or =10/sup 4/ cm/sup -3/) are generally required to account for the observed lines; the J=1. -->. 0 transition of HC/sub 3/N in Sgr B2 probably a weak maser. Several sources are discussed individually. (AIP)
Uniform Asymptotic Po Diffraction Coefficients for an Anisotropic Impedance Half-Plane

Uniform asymptotic Physical Optics diffraction coefficients for an anisotropic half-plane illuminated at oblique incidence are given in this paper. From the electromagnetic viewpoint such a structure is characterized by suitable anisotropic impedance boundary conditions. The principal axes of anisotropy can be not coincident with the half-plane edge. The solution is obtained by using a Physical Optics approximation of the equivalent surface current densities on the half-plane and by performing an uniform asymptotic evaluation of the radiation integral. Some numerical results are reported to demonstrate the effectiveness of the proposed approach.
The International Journal of Biostatistics Properties of the Projected Length of the Curve ( PLC ) and Area Swept out by the Curve ( ASC ) Indices for the Receiver Operating Characteristic ( SROC ) Curve

Several measures have been proposed to summarize the Receiver Operating Characteristic (ROC) curve, including the Projected Length of the Curve (PLC) and the Area Swept out by the Curve (ASC). These indices were first proposed by Lee (Epidemiology 1996; 7:605-611) to avoid certain deficiencies of the traditional Area Under the Curve (AUC) summary measure. More recently meta-analysis methods for assessing diagnostic test accuracy have been developed and the Summary Receiver Operating Characteristic (SROC) curve has been recommended to represent the performance of a diagnostic test. Some properties of the SROC curve were discussed by Walter (Statist. Med. 2002; 21:1237-1256). Here we extend that work to focus on properties of PLC and ASC in the context of SROC curve. Mathematical expressions for these two indices and their variances are derived in terms of the overall diagnostic odds ratio and the magnitude of interstudy heterogeneity in the odds ratio. Expressions for PLC and ASC and their variances are easily computed in homogeneous studies, and their values provide good approximations to the corresponding values for heterogeneous studies in most practical situations. General variances of PLC and ASC are derived by using delta methods, and are found to be smaller if the odds ratio is large. The methods are illustrated using data from two studies, the first being a meta-analysis on the detection of metastases in cervical cancer patients, and the second being a single study of HPV infection and pre-invasive cervical lesions.
Large eddy simulation of compartment fires

This paper is aimed at illustrating the capabilities of contemporary large eddy simulation (LES) solvers for compartment fire applications. Compartment fires refer to fires occurring indoors and feature a variety of complex phenomena associated with smoke accumulation and restricted air ventilation. The article provides a brief presentation of the main features of compartment fire dynamics followed by a review of the modelling challenges found in a LES treatment of these dominant features. The discussion shows that in addition to a suitable model for the turbulent flow dynamics, simulations of compartment fires require a collection of physical sub-models in order to describe a large range of multi-physics phenomena, including pyrolysis processes, buoyancy-driven flow, combustion, soot formation and thermal radiation. Some examples of LES simulations of compartment fires are also presented, using two different solvers that represent the current state-of-the-art of compartment fire modelling: FDS developed by the National Institute of Standards and Technology, USA, and FireFOAM developed by FM Global, USA. Both solvers are available as free open-source software and are representative of ongoing efforts within the fire research and engineering community to self-organise and to promote the general area of LES-based fire modelling.
2M0415+0154: a new bright, short-period subdwarf B pulsator

Context. The discovery of stellar oscillations in some subdwarf B stars presents the opportunity of studying the interior structure of these objects, thereby clarifying their possible formation channels. Aims. Our ongoing survey attempts to increase the number of pulsating hot subdwarfs to better understand the complexities of the various subgroups within the population of pulsators and to identify targets suitable for seismological analysis. Methods. Light curves for a list of potential pulsators were obtained at the Nordic Optical Telescope. The candidates were mainly selected based on similar T eff and log g as known pulsators. A frequency analysis of the light curves was performed to investigate the multiperiodic photometric variability. Results. From the sample we surveyed in 2007, 2M0415+0154 was the only star clearly showing photometric modulations. Follow-up photometry revealed three clear pulsation modes with periods between 143 and 150 s. Additional spectroscopic data was taken on 2M0415+0154 to refine its physical parameters. We find T eff = 34 000 ± 500 K, log g = 5.80 ± 0.05 dex, log (N He /N H ) = -1.60 ± 0.05, which are typical of sdB pulsators in this period range. No evidence of a companion was found. Conclusions. A new short-period sdB star has been discovered, 2M0415+0154. Its physical parameters and oscillation frequencies agree with those of other V361 Hya stars. The relative brightness and simple frequency spectrum of this star make it a suitable target for empirical mode identification, essential for a seismological analysis of simple pulsators.
Greatest common divisor via generalized Sylvester and Bezout matrices

We present new methods for computing the greatest common right divisor of polynomial matrices. These methods involve the recently studied generalized Sylvester and generalized Bezoutian resultant matrices, which require no polynomial operations. They can provide a row proper greatest common right divisor, test for coprimeness and calculate dual dynamical indices. The generalized resultant matrices are developments of the scalar Sylvester and Bezoutian resultants and many of the familiar properties of these latter matrices are demonstrated to have analogs with the properties of the generalized resultant matrices for matrix polynomials.
Precise measurement of density and structure of undercooled molten silicon by using synchrotron radiation combined with electromagnetic levitation technique

X-ray diffraction and density measurements have been simultaneously performed to investigate the atomic structure of molten silicon in a wide temperature range including the undercooling region by using the electromagnetic levitation technique. The density was obtained from the mass and the shape of a levitated sample by a non-contact method based on the image analysis technique. X-ray diffraction experiments were performed by using the synchrotron radiation at SPring8, Japan. From structural analysis of undercooled molten silicon, the first nearest neighbour coordination numbers and interatomic distances were about 5 and 2.48 Å with no dependence on temperature in the range of 1900–1550 K. We conclude as a result that the short-range order based on tetrahedral bonds of undercooled molten silicon does not change with the degree of undercooling but that medium-range order changes by the degree of undercooling.
TWO-STEP ACCELERATION MODEL OF COSMIC RAYS AT MIDDLE-AGED SUPERNOVA REMNANTS: UNIVERSALITY IN SECONDARY SHOCKS

Recent gamma-ray observations of middle-aged supernova remnants revealed a mysterious broken power-law spectrum. Using three-dimensional magnetohydrodynamic simulations, we show that the interaction between a supernova blast wave and interstellar clouds formed by thermal instability generates multiple reflected shocks. The typical Mach numbers of the reflected shocks are shown to be M≃ 2 depending on the density contrast between the diffuse intercloud gas and clouds. These secondary shocks can further energize cosmic-ray particles originally accelerated at the blast-wave shock. This “two-step” acceleration scenario reproduces the observed gamma-ray spectrum and predicts the high-energy spectral index ranging approximately from 3 to 4.
Circulation anomalies associated with tropical convection during northern winter

Abstract Lagged cross correlations between outgoing longwave radiation (OLR) and National Meteorological Center global analyses are utilized to isolate the preferred upper-level and surface circulation anomalies associated with tropical convection during northern winter. Three intraseasonal time scales are studied: 30–70, 14–30, and 6–14 days. In the 30–70-day band, the upper-level circulation signals are zonally elongated, with zonal wavenumbers 0–2 dominant. Higher-frequency signals are dominated by zonal wavenumbers 5 and 6. In the 14–30-day band, convection over the eastern hemisphere is associated with upper-level anticyclones in the subtropics and appears to be linked in some cases to midlatitude wave trains. The strongest signals are for convection over Africa, Australia, and the eastern Indian Ocean. Only weak signals are seen for convection over Indonesia. In these regions of upper-level easterlies, OLR anomalies peak prior to the maximum anomalies in wind, suggesting forcing of the circulation b.
Gyrokinetic modelling of electron and boron density profiles of H-mode plasmas in ASDEX Upgrade

Local gyrokinetic calculations of the logarithmic gradients at mid-radius of both electron and boron densities in ASDEX Upgrade H-mode plasmas are presented and compared with the experimental observations. The experimental results show that both the electron and the boron density profiles increase their peaking in response to the addition of central electron cyclotron heating over a background of neutral beam injection (NBI) heating. The boron density profiles are always less peaked than the electron density profiles in the confinement region, and are flat or even slightly hollow in the presence of NBI heating only. The experimental behaviours are well reproduced by the theoretical predictions. The agreement allows the identification, through theoretical modelling, of the transport mechanisms responsible for the observed dependences. In particular, the observed increase in the logarithmic electron density gradient with increasing central electron heating is explained by a concurrent reduction of the outward pure convection and an increase in the inward thermodiffusion. In addition, it is found that the plasma toroidal rotation velocity and its radial gradient play a non-negligible role in the turbulent boron transport, and allow the prediction of a decrease in boron peaking with increasing rotation velocity, which is consistent with the experimental observations.
Effects of Screw Clearance and Blend Ratio on The Flow and Mixing Characteristics of Tri-Screw Extruders In Cross Section With CFD

Abstract A triangularly-arranged tri-screw extruder (TATSE) is a new piece of equipment for polymer processing, which has a dynamic center region. To learn about the special contributions of the dynamic center region and the circumfluence phenomenon just in cross section on the mixing mechanism of the TATSE, the 2D computational fluid dynamics (CFD) model was established to reduce the axial effect. The effects of screw clearances of the center region on mixing mechanism of the TATSE were studied. The mixing evaluations for the TATSE and twin-screw extruder (TSE) with different screw clearances were performed and compared. Moreover, the effects of different blend mass ratios of LLDPE and SBS on the mixing efficiency of the TATSE were studied. The results show that as screw clearances increase, the values of mean time-averaged and instantaneous efficiencies of the tri-screw extruder increase, but the normalized segregation scale decreases. The screw clearances even change the particle conditions from stretch to compression in the center region.
Learning in lectures: multiple representations

Lectures remain the lynchpin of mathematics teaching at university even with advances in information technology and access to the internet. This paper examines the requirements for learning mathematics and shows how important it is for lecturers to be aware of the different modes of presentation they are using. Ways to assist students to make the connections between different representations are considered, with particular reference to students whose first language is not English.
Space-time and integral measures of individual accessibility: a comparative analysis using a point-based framework

Conventional integral measures of accessibility, although valuable as indicators of place accessibility, have several limitations when used to evaluate individual accessibility. Two alternatives for overcoming some of the difficulties involved are explored in this study. One is to adapt these measures for evaluating individual accessibility using a disaggregate, nonzonal approach. The other is to develop different types of measures based on an alternative conceptual framework. To pursue the former alternative, this study specifies and examines eighteen gravity-type and cumulative-opportunity accessibility measures using a point-based spatial framework. For the latter option, twelve space-time accessibility measures are developed based on the construct of a prism-constrained feasible opportunity set. This paper compares the relationships and spatial patterns of these thirty measures using network-based GIS procedures. Travel diary data collected in Columbus, Ohio, and a digital data set of 10,727 selected land parcels are used for all computation. Results of this study indicate that space-time and integral indices are distinctive types of accessibility measures which reflect different dimensions of the accessibility experience of individuals. Since space-time measures are more capable of capturing interpersonal differences, especially the effect of space-time constraints, they are more “gender sensitive” and helpful for unraveling gender/ethnic differences in accessibility. An important methodological implication is that whether accessibility is observed to be important or different between individuals depends heavily on whether the measure used is capable of revealing the kind of differences the analyst intends to observe.
Ideal and resistive interchange instabilities in negative shear tokamaks and currentless heliotron plasmas

For tokamaks the ideal localized interchange mode does not play a role for cases of q (safety factor) >1 over the whole plasma region, whereas in heliotron plasmas the mode becomes unstable in the edge region owing to the magnetic hill. However, for negative shear tokamaks, the resistive localized interchange mode becomes unstable where q0 is much larger than qmin, where q0 (qmin) is the central (minimum) q value. With the appropriate ellipticity and triangularity the stability against the resistive interchange mode is significantly improved. It is also shown that ideal and resistive non-resonant global interchange modes appear easily in the central region of heliotrons and in negative shear tokamaks; the modes are similar to the infernal mode in low shear tokamaks.
Generation of a ULF wave resonator in the magnetosphere by neutral gas release

[1] ULF waves generated by the release of a neutral gas in the equatorial plane of the Earth's magnetosphere will be trapped between two turning points forming a resonator. This effectively prolongs the lifetime of the ensuing turbulence making it more useful for pitch angle scattering trapped energetic electrons. In the multispecies plasma environment of the magnetosphere, the presence of a small amount of helium causes the waves to reflect when their frequency matches the Buchsbaum frequency as they travel along field lines away from the equator. For a proton-electron-helium plasma, the Buchsbaum frequency is near the helium cyclotron frequency. With typical abundances of helium in the inner radiation belts, there is virtually no loss of wave energy by cyclotron damping at the turning points as the waves reflect between conjugate Buchsbaum points. Wave energy is eventually dissipated by collisional effects and radial convection.
An Inverse Heat Conduction Problem and Improving Shielded Thermocouple Accuracy

A shielded thermocouple is a measurement device used for monitoring the temperature in chemically, or mechanically, hostile environments. The sensitive parts of the thermocouple are protected by a shielding layer. In order to improve the accuracy of the measurement device, we study an inverse heat conduction problem where the temperature on the surface of the shielding layer is sought, given measured temperatures in the interior of the thermocouple. The procedure is well suited for real-time applications where newly collected data is continuously used to compute current estimates of the surface temperature. Mathematically we can formulate the problem as a Cauchy problem for the heat equation, in cylindrical coordinates, where data is given along the line r = r 1 and the solution is sought at r 1 < r ≤ r 2. The problem is ill-posed, in the sense that the solution (if it exists) does not depend continuously on the data. Thus, regularization techniques are needed. The ill–posedness of the problem is analyzed and a numerical method is proposed. Numerical experiments demonstrate that the proposed method works well.
A Note on Determining the Number of Imputations for Missing Data

A desirable method for imputing missing data when the missing data mechanism is ignorable is random imputation. Imputation generally involves regressing each variable with missing data onto all the other variables. Single random imputation involves creating one data set in which each of the missing values is imputed by adding a random error term from the residual distribution of each imputed variable. Adding a random error term reduces the bias in standard errors of parameter estimates ordinarily observed under traditional methods of imputation (Schafer, 1997). However, even single random imputation produces standard errors that are generally biased downward and parameter estimates that are relatively inefficient. Improvements in bias and efficiency occur with multiple random imputation in which the imputation process is done more than once, producing multiple data sets whose parameter estimates and standard errors are averaged (Rubin, 1987). Many structural equation modeling programs (e.g., AMOS; Arbuckle, 1997) are now able to compute multiple random imputations for missing data. Relatively little guidance has been given as to the number of imputations that should be conducted. Is two enough? Are the five imputations given as the default in PROC MI of Statistical Analysis System (SAS, 2002) enough? Or, is some greater value required? Based on the results of a Monte Carlo study, Rubin and Schenker (1986; see also Li, Raghunathan, & Rubin, 1991) suggested that the number of imputations per missing value should be roughly two when 10% STRUCTURAL EQUATION MODELING, 10(4), 648–650 Copyright © 2003, Lawrence Erlbaum Associates, Inc.
User Profile Construction Based on Multi-Channel Fusion

Aiming at the shortcomings of existing user profile construction algorithms that do not fully utilize contextual structural information and multidimensional feature information. , a user profile construction model based on the pre-training model NEZHA, Deep Pyramidal Convolutional Neural Networks (DPCNN), Gated Recurrent Unit (GRU), and attention mechanism is proposed, NCDGA. The method uses multiple channels to process the text, capturing different dimensions of information and constructing features to reduce the prediction bias that occurs when a single model captures a single feature. The experimental results show that the NCDGA model has better accuracy and effectiveness compared with other modeling methods.
A Duality Theorem for Non-Linear Programming

In this paper, a dual problem is formulated for non-linear programming problem of minimising a convex function under concave constraints and non-negativity restrictions on the variables (x1, x2…, xn). The problem of P. Wolfe has been discussed with considerably reduced number of variables known as Lagrange multipliers ui. Mainly two results have been established: (a) the infimum for primal is greater or equal to the supremum of the dual under their respective constraints, (b) Principal Duality Theorem. Finally a numerical example has been solved to exhibit important results of the paper. Betrachtet wird die Aufgabe, eine konvexe Funktion unter konkaven Nebenbedingungen und Nichtnegativitatsforderungen fur die Variablen x1, x2, …, xn zu minimieren. Fur dieses nichtlineare Programmierungsproblem, wird ein duales Problem formuliert. Dadurch last sich die Zahl der Lagrangeschen Multiplikatoren ui bei der Behandlung des Problems von P. Wolfe betrachtlich verringern. Die wesentlichen Resultate sind: (a) Das Infimum fur das primale Problem ist nicht kleiner als das Supremum fur das duale Problem unter entsprechenden Bedingungen, (b) der Hauptsatz der Dualitat. Zum Schlus wird an einem Zahlenbeispiel die Bedeutung der Resultate demonstriert.
Charge ordering in half-doped manganites

Alternative descriptions for the ground state structure of the half-doped manganite ${\mathrm{Pr}}_{0.5}{\mathrm{Ca}}_{0.5}\mathrm{Mn}{\mathrm{O}}_{3}$ have been tested against high-resolution $10\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ x-ray and neutron powder diffraction data. The best fit is obtained using a $P{2}_{1}∕m$ symmetry model, which supports the striped charge and orbital ordering picture. The magnitude of the charge ordering is, however, only 25% of the ideal ${\mathrm{Mn}}^{3+}∕{\mathrm{Mn}}^{4+}$ separation. An alternative $Pnm{2}_{1}$ pseudosymmetry, used to describe Zener polaron ordering in ${\mathrm{Pr}}_{0.6}{\mathrm{Ca}}_{0.4}\mathrm{Mn}{\mathrm{O}}_{3}$ [Phys. Rev. Lett. 89, 097205 (2002)], gives a different, bistriped, charge and orbitally ordered model that does not fit the data as well.