Miracle-dz/UniFAR-FTUs huggingface dataset:
On overdamping phenomena in gyroscopic systems composed of high-loss and lossless components

Using a Lagrangian framework, we study overdamping phenomena in gyroscopic systems composed of two components, one of which is highly lossy and the other is lossless. The losses are accounted by a Rayleigh dissipative function. As we have shown previously, for such a composite system the modes split into two distinct classes, high-loss and low-loss, according to their dissipative behavior. A principal result of this paper is that for any such system a rather universal phenomenon of selective overdamping occurs. Namely, first of all the high-loss modes are all overdamped, i.e., non-oscillatory, as are an equal number of low-loss modes. Second of all, the rest of the low-loss modes remain oscillatory (i.e., the underdamped modes) each with an extremely high quality factor (Q-factor) that actually increases as the loss of the lossy component increases. We prove that selective overdamping is a generic phenomenon in Lagrangian systems with gyroscopic forces and give an analysis of the overdamping phenomena in such systems. Moreover, using perturbation theory, we derive explicit formulas for upper bound estimates on the amount of loss required in the lossy component of the composite system for the selective overdamping to occur in the generic case, and give Q-factor estimates for the underdamped modes. Central to the analysis is the introduction of the notion of a "dual" Lagrangian system and this yields significant improvements on some results on modal dichotomy and overdamping. The effectiveness of the theory developed here is demonstrated by applying it to an electric circuit with a gyrator element and a high-loss resistor.
Data Quality of the Meteo-France C-Band Polarimetric Radar

Abstract The French operational radar network is being upgraded and expanded from 2002 to 2006 by Meteo-France in partnership with the French Ministry of the Environment. A detailed examination of the quality of the raw polarimetric variables is reported here. The analysis procedures determine the precision of the measurements and quantify errors resulting from miscalibration, near-radome interference, and noise effects. Correction methods to remove biases resulting from effective noise powers in the horizontal and vertical channels, radar miscalibration, and the system offset in differential propagation phase measurements are presented and evaluated. Filtering methods were also required in order to remove azimuthal dependencies discovered with fields of differential reflectivity and differential propagation phase. The developed data quality analysis procedures may be useful to the agencies that are in the process of upgrading their radar networks with dual-polarization capabilities.
Lack of SIRP‐alpha reduces lung cancer growth in mice by promoting anti‐tumour ability of macrophages and neutrophils

Signal regulatory protein‐alpha (SIRPα) is a transmembrane glycoprotein specifically expressed on myeloid cells. Blockade of SIRPα/CD47 interaction is effective in combinational therapy of some cancers. This study aimed to explore into the role and underlying molecular mechanisms of SIRPα in lung cancer growth.
BPS STATES AND THE P = W CONJECTURE

A string theoretic framework is presented for the work of Hausel and Rodriguez-Vilegas as well as de Cataldo, Hausel and Migliorini on the cohomology of character varieties. The central element of this construction is an identification of the cohomology of the Hitchin moduli space with BPS states in a local Calabi-Yau threefold. This is a summary of several talks given during the Moduli Space Program 2011 at Isaac Newton Institute.
Universal cell-like maps

The main results of the paper are the following: Theorem. Suppose n < oo. There is a cell-like map f: X -Y of complete and separable metric spaces such that dim X < n, and for any cell-like map f' : X' -Y' of (complete) separable metric spaces with dim X' < n there exist (closed) embeddings i: Y' -* Y and j: X' -* f1(i(Y')) such that fi = if'. Corollary. Suppose n < oo. There is a complete and separable metric space Y such that dimz Y < n, and any (complete) separable metric space Y' with dimz Y' < n embeds as a (closed) subset of Y.
Comments on “A Statistical Determination of the Random Observational Errors Present in Voluntary Observing Ships’ Meteorological Reports”

Abstract The accuracy achievable for surface ship pressure reports and the sources of error in them are discussed. In The Met Office numerical weather prediction (NWP) system the error is estimated as 1 hPa, whereas Kent et al. calculated a figure of about 2.3 hPa. There are a number of reasons for this discrepancy, but the main one is that quality control using short-range forecasts is much better at detecting gross errors in the reports than are climatological checks. Statistics from the Met Office NWP system are presented for comparison of pressure and other atmospheric variables. Other variables show much less discrepancy than pressure because, relative to observation error, they have a smaller climatological range. Both sets of statistics show larger air temperature errors at high latitudes/low temperatures.
A mixed variational discretization for non-isothermal compressible flow in pipelines

We consider the non-isothermal flow of a compressible fluid through pipes. Starting from the full set of Euler equations, we propose a variational characterization of solutions that encodes the conservation of mass, energy, and entropy in a very direct manner. This variational principle is suitable for a conforming Galerkin approximation in space which automatically inherits the basic physical conservation laws. Three different spaces are used for approximation of density, mass flux, and temperature, and we consider a mixed finite element method as one possible choice of suitable approximation spaces. We also investigate the subsequent discretization in time by a problem adapted implicit time stepping scheme for which exact conservation of mass as well as a slight dissipation of energy and increase of entropy are proven which are due to the numerical dissipation of the implicit time discretization. The main arguments of our analysis are rather general and allow us to extend the approach with minor modification to more general boundary conditions and flow models taking into account friction, viscosity, heat conduction, and heat exchange with the surrounding medium.
Stable Manifolds of Two-dimensional Biholomorphisms Asymptotic to Formal Curves

Let $F\in\, \textrm{Diff}\, ({\mathbb{C}}^2, 0)$ be a germ of a holomorphic diffeomorphism and let $\Gamma $ be an invariant formal curve of $F$. Assume that the restricted diffeomorphism $F|_\Gamma $ is either hyperbolic attracting or rationally neutral non-periodic (these are the conditions that the diffeomorphism $F|_\Gamma $ should satisfy, if $\Gamma $ were convergent, in order to have orbits converging to the origin). Then we prove that $F$ has finitely many stable manifolds, either open domains or parabolic curves, consisting of and containing all converging orbits asymptotic to $\Gamma $. Our results generalize to the case where $\Gamma $ is a formal periodic curve of $F$.
On the initial stages of AlN thin-film growth onto (0001) oriented Al2O3 substrates by molecular beam epitaxy

Conventional and high-resolution transmission electron microscopy are used to characterize the initial stages of AlN thin-film growth. AlN films are deposited by molecular beam epitaxy onto annealed (0001) oriented α-Al2O3 (sapphire) substrates. During the initial stages of film growth (film thickness ∼25 nm) AlN forms islands of varying alignment with the Al2O3 substrate. Some of the AlN islands are well aligned with the [1120]AlN∥[1010] Al2O3 and (0001)AlN∥(0001)Al2O3, which matches closed-packed planes and directions. Other islands exhibit either an alignment of one set of planes, i.e., grains are aligned with the (1101)AlN∥(1120) Al2O3, or are misaligned with respect to the Al2O3 substrate. As the AlN film grows in thickness (film thickness ∼100 nm), the film becomes continuous, and the closed-packed planes and directions of the film and substrate are aligned for the majority of the film. Islands of AlN with an alignment other than this predominant orientation disturb the growth near the AlN/Al2O3.
Color Machine Vision Design Methodology of a Part-Presentation Algorithm for Automated Poultry Handling

This article offers an image processing method to optimize the design of a three-level color machine vision algorithm illustrated in the context of presenting a whole chicken carcass for subsequent handling, which overcomes some common problems in image segmentation, feature identification, and pose estimation for classifying, identifying, and locating poultry meat products. First, artificial color contrast and principal component analysis are optimized to enhance the contrast between similar colors to extract targeted regions more effectively. Second, the boundaries of poultry products are mostly smooth curves that are proposed as features for object recognition. Third, image feature points are found using template matching, from which the object (size, location, and pose) can be accurately determined. The algorithm simplifies the complex edges of a poultry product into a finite number of arc-centers, which greatly improves the efficiency/accuracy of the matching for part-presentation. Evaluated with 100 randomly posed samples, the algorithm has a success rate of 93%. The 7% failures were primarily due to missing points, which can be eliminated by incorporating more template points.
Photoinduced photoluminescence intensity enhancement in poly(p-phenylene vinylene) films

We report measurements of photoluminescence (PL) intensity enhancement in poly(p-phenylene vinylene) (PPV) films induced by light irradiation in the presence of air. This effect is dependent on laser intensity and the ratio between film thickness and excitation penetration depth. The results suggest that an efficient spectral diffusion of excited carriers to nondegraded PPV segments by Forster energy transfer is an important consideration in the PL efficiency of conjugated polymers light-irradiated in air.
Robust Measurement of (Heavy-Tailed) Risks: Theory and Implementation

Every model presents an approximation of reality and thus modeling inevitably implies model risk. We quantify model risk in a non-parametric way, i.e., in terms of the divergence from a so-called nominal model. Worst-case risk is defined as the maximal risk among all models within a given divergence ball. We derive several new results on how different divergence measures affect the worst case. Moreover, we present a novel, empirical way built on model confidence sets (MCS) for choosing the radius of the divergence ball around the nominal model, i.e., for calibrating the amount of model risk. We demonstrate the implications of heavy-tailed risks for the choice of the divergence measure and the empirical divergence estimation. For heavy-tailed risks, the simulation of the worst-case distribution is numerically intricate. We present a Sequential Monte Carlo algorithm which is suitable for this task. An extended practical example, assessing the robustness of a hedging strategy, illustrates our approach.
Novel Mucoadhesive Chitosomes as a Platform for Enhanced Oral Bioavailability of Cinnarizine

Purpose Cinnarizine (CIN) is a class II BSC drug, suffering from erratic bioavailability due to its pH-dependent solubility. It has preferential absorption in the stomach. In this study, new chitosan (CS) coated niosomes of CIN (CIN-loaded chitosomes) have been developed to extend the gastric retention and ameliorate CIN oral bioavailability. Methods Various CIN-loaded niosomes were fabricated by thin-film hydration technique and fully characterized. Based on the predetermined criteria of low particle size (PS) and high entrapment efficiency percent (EE%), niosomal formulation F1 was selected and further coated with different CS concentrations. The optimized chitosomal formulation (C2) was evaluated through solid state characterization and mucoadhesive efficiency testing. It was also subjected to cytotoxicity study on Caco-2 cells; besides, in vitro drug release, stability and pharmacokinetic studies were assessed. Results The optimized chitosomal formulation (C2) exhibited an EE% of 58.30±2.75%, PS of 440 ±13.03 nm, PDI of 0.335±0.21 and ZP of +28.1±0.10 mv. Solid state characterization results revealed the compatibility between the vesicle components and the entrapment of CIN within niosomal vesicles. C2 formulation demonstrated favorable mucoadhesive efficiency. The cytotoxicity study on Caco-2 cells manifested the safety of the optimized chitosomal formulation (C2) over the free drug. Additionally, it displayed a remarkable sustaining of CIN in vitro release up to 8 h and exhibited a good stability at the refrigerated temperature up to 3 months. In vivo pharmacokinetic assessment revealed that the CIN bioavailability from the optimized chitosomal formulation C2 was enhanced by 2.79 and 1.92 folds compared to the free drug and uncoated niosomal formulation F1, respectively. The priority of the chitosomal formulation (C2) over the niosomal one (F1) was also conferred. Conclusion Novel formulation of chitosan coated niosomes (chitosomes) could be presented as a promising platform to improve the oral bioavailability of drugs with narrow absorption window.
Methods of constructing grid approximations for singularly perturbed boundary-value problems. Condensing-grid methods

The Dirichlet boundary-value problem for the elliptic equation is treated on a rectangle. The highest derivatives of the equation contain a parameter taking on the values on a half-open interval (0,1]. For the zero value of the parameter, the elliptic equation degenerates into a first-order one. The method of special condensing grids is used to solve the boundary-value problem. The conditions providing uniform convergence of the difference schemes in the parameter are specified for the node distribution of the grids being constructed and for the grid approximations of differential equations. Various methods of constructing such grid approximations of the boundary-value problem that meet the conditions sufficient for the schemes being constructed to converge uniformly in the parameter, are given. Several schemes are constructed for the boundary-value problem involved. Computer-aided grid methods are used for the solution of many applied problems which reduce to differential equations. In the classical theory these methods are developed and studied under the assumption that a solution is smooth enough. The accuracy of a grid method depends on the solution smoothness and, generally speaking, degrades down to a complete loss of accuracy, if the solution smoothness worsens [2,19,21,22]. The solutions of many numerical problems possess a limited smoothness in some rather small parts of the solution definition domain due to the peculiarities of the solution itself or its lower-order derivatives. Among the problems of the kind are boundary-value problems for singularly perturbed differential elliptic or parabolic equations, in particular, boundary-value problems in the domains with non-smooth boundaries. Even at a fixed value of the parameter, the solution derivatives entering into the equations have peculiarities, which are aggravated by the appearance of boundary layers as the parameter tends to zero [6,7,27]. When applied to such singularly perturbed boundary-value problems, the classical grid methods which have been developed for the problems with smooth solutions, fail to yield approximate solutions converging uniformly in the parameter. For example, the use of the classical difference schemes on uniform grids with an arbitrarily small step results in a complete loss of accuracy of an approximate solution even in the case of ordinary differential equations, at sufficiently small values of the parameter [8,13]. The following approaches to constructing special numerical methods for the problems with non-smooth solutions may be cited: (1) the approach connected with the additive isolation of a peculiarity of the solution being approximated [3,4]; (2) the approach based on the grids condensing in the vicinity of peculiar sets [5,15]; (3) the approach that employs the fitting schemes whose variable coefficients are
Heat Capacity Study of PMN Near Field—Induced Phase Transition

Heat capacity measurements were performed for a single crystal wafer of PMN in the temperature range of 170–250 K applying an electric field E = 3.0 kV/cm along the [111] direction. The heat capacity anomalies related to the phase transition at T c = 210 K upon zero field heating after field cooling and at T c = 223 K upon field cooling have been found. The results obtained are discussed together with the data of previous studies in the frame of the spherical random bond—random field model.
Theoretical investigation of electromagnetic waves in a dielectric loaded coaxial plasma waveguide

A theoretical study of high frequency eigenmodes of a dielectric loaded coaxial waveguide in the presence of an annular plasma column is presented. A uniform axial magnetic field is applied to maintain the plasma position inside the waveguide. The dispersion equation is derived through the application of the appropriate boundary conditions which results in an eighth order determinant. The eigenmodes are determined by equating this determinant to zero. In the presence of the dielectric layer on the conducting surfaces, the azimuthally symmetric modes have been identified as HE, EH, cyclotron, and space charge modes for the coaxial waveguide. A comparison of the numerical analyses of this study with the results of the previous investigations indicates that there is a considerable rise in the frequencies of the waveguide modes.
Two-state model of self-organized criticality

Studies a two-state version of the sandpile model of self-organized criticality. Instead of a critical height of stability as in the sandpile model, the author introduces a hard core repulsion among different particles at the same position. In the case of a collision particles hop randomly to the nearest neighbours. Critical exponents obtained by numerical simulation show strong disagreement with the values theoretically predicted for the sandpile model but they are close to the numerical values of other models.
Rapid neutral–neutral reactions at low temperatures: a new network and first results for TMC‐1

There is now ample evidence from an assortment of experiments, especially those involving the CRESU (Cinetique de Reaction en Ecoulement Supersonique Uniforme) technique, that a variety of neutral–neutral reactions possess no activation energy barrier and are quite rapid at very low temperatures. These reactions include both radical–radical systems and, more surprisingly, systems involving an atom or a radical and one ‘stable’ species. Generalizing from the small but growing number of systems studied in the laboratory, we estimate reaction rate coefficients for a larger number of such reactions and include these estimates in a new network of gas-phase reactions for use in low-temperature interstellar chemistry. Designated osu.2003, the new network is available on the World Wide Web and will be continually updated. A table of new results for molecular abundances in the dark cloud TMC-1 (CP) is provided and compared with results from an older (new standard model; nsm) network.
Seventy-Five Years since the Point-Contact Transistor: Germanium Revisited

The advent of the point-contact transistor is one of the most significant technological achievements in human history with a profound impact on human civilization during the past 75 years. Although the first transistor was made of germanium it was soon replaced by silicon, a material with lower intrinsic carrier mobilities but with a substantially better native oxide. Interestingly, more than two decades ago, germanium was once again considered as a mainstream microelectronic material, since the introduction of high-k dielectrics allowed the consideration of channel materials irrespective of the quality of their native oxide. After about 50 years of limited studies on the defect processes in germanium, the community once again focused on its applicability for mainstream electronic applications. Nevertheless, there are some bottlenecks that need to be overcome, and it was the aim of the present review to discuss the progress in the understanding of the defect processes of Ge.
Indonesian Coffee at The International Market

The research was conducted to know the competitiveness of coffee in the international market both comparatively and competitively. Measuring the strength of competitiveness in this study was conducted based on comparative analysis (analysis of RCA index, Herfindahl and CR4 Index, and Trade Specialization Index / ISP) and to analyze the competitive advantage of Indonesian coffee (Berlin Porter'/ Porter's Diamond Theory theory) to see the demand and supply side of the market. The results of this study revealed that the competitiveness of Indonesian coffee is very strong supported by the average RCA value of 4.08, the Herfindahl Index which shows free competition and reveals that the market ratio includes low market concentration and Indonesia based on the Market Specialization Index including exporting countries.
Polynomial interpolation and a priori bootstrap for computer-assisted proofs in nonlinear ODEs

In this work, we introduce a method based on piecewise polynomial interpolation to enclose rigorously solutions of nonlinear ODEs. Using a technique which we call a priori bootstrap , we transform the problem of solving the ODE into one of looking for a fixed point of a high order smoothing Picard-like operator. We then develop a rigorous computational method based on a Newton-Kantorovich type argument (the radii polynomial approach) to prove existence of a fixed point of the Picard-like operator. We present all necessary estimates in full generality and for any nonlinearities. With our approach, we study two systems of nonlinear equations: the Lorenz system and the ABC flow. For the Lorenz system, we solve Cauchy problems and prove existence of periodic and connecting orbits at the classical parameters, and for ABC flows, we prove existence of ballistic spiral orbits.
Influences of short-chain alcohols, urea and temperature on aggregation behaviour of tetradecyltrimethylammonium bromide and antidiabetic drug mixture

In this investigation, the supramolecular interaction between a surfactant- tetradecyltrimethylammonium bromide (TTAB) and an antidiabetic drug metformin hydrochloride (MNH) was studied in the presence of some additives (alcohols/urea). The conductometric analysis as a function of surfactant concentration was used to assess the critical micelle concentration (CMC) of TTAB + MNH mixed system. The effect of a gradual change of temperature on CMC within a certain range (298.15–318.15 K) was monitored to assess the thermodynamic nature of micellisation process. In addition, estimation of thermodynamic parameters ( , , and ) and the determination of the degree of counter ion binding (β) give insight into the relative viability of a micellisation process. The values of were negative in all the mixed solvents studied and this was dependent on the chain length of the used alcohols. The thermodynamic parameters of transfer for shifting the micelles from aq. medium to aq. alcohols media and enthalpy-entropy compensation were also computed, compared with literature values and discussed with appropriate reasoning. Several supramolecular forces, including H-bonds, dipole–dipole, ion-dipole, hydrophobic, and electrostatic interactions, were recommended for the aggregation of the TTAB + MNH system. GRAPHICAL ABSTRACT