Miracle-dz/UniFAR-FTUs huggingface dataset:
Field theoretic and Monte Carlo analysis of the Domb - Joyce model

We present a field-theoretic analysis of high-precision Monte Carlo data for the Domb - Joyce model on the sc lattice. We vary the repulsion between two segments at the same point from zero (random walk) to infinity (self-avoiding walk). Eventually, we even include a repulsion between segments at neighbour points to increase the excluded volume beyond that of self-avoiding walks. The data for the end-to-end distance, the radius of gyration and the partition function clearly show the existence of two branches of universal behaviour. These two branches can be identified with the weak- and strong-coupling branch of the renormalization group, respectively. A quantitative analysis shows the ability of the standard field theoretic approach to describe the data, including the data for strong coupling, i.e. renormalized coupling u greater than its fixed point value . We conclude, in contrast with some claims in the literature, that the standard formalism of the renormalized field theory can be used even for (strong-coupling branch). In addition, exploiting the fast approach to asymptotic behaviour at the transition between weak and strong coupling, we obtain very precise estimates for the critical exponents of self-avoiding walks.
Is politics power or policy oriented? A comparative analysis of dynamic access models in policy networks

We will show that these base models and some intermediate ones result in fundamentally different network structures and predicted outcomes. Moreover, we will show that the policy driven models do fundamentally better than the power driven models. In policy networks actors use access relations to influence preferences of other actors. Establishment and shifts of access relations and their consequences for outcomes of decisions are the main focal points in this paper. Unlike most policy network studies, we therefore do not take the network and its relations as given and constant. Instead we device computer simulation models to account for the dynamics in policy networks. We compare different models and investigate the resulting network structures and predicted outcomes of decisions. The choice among the alternative models is made by their correspondence with empirical network structures and actual outcomes of decisions. In our models, we assume that all relevant actors aim at policy outcomes as close as pos.
Signature, Nullity And Determinant Of Checkerboard Colorable Virtual Links

In this paper, we present the Goeritz matrix for checkerboard colorable virtual links or, equivalently, checkerboard colorable links in thickened surfaces Sg × [0, 1], which is an extension of the Goeritz matrix for classical knots and links in ℝ3. Using this, we show that the signature, nullity and determinant of classical oriented knots and links extend to those of checkerboard colorable oriented virtual links.
Dynamic response of constant temperature hot-wire systems under various perturbations

Differential equations of constant temperature hot-wire systems are solved numerically under various perturbation methods. The results show that cut-off frequencies determined from traditional square wave tests are inconsistent with those from velocity impulses at hot wires, with the latter being the proper method for dynamic systems such as hot-wire anemometers. It is also found that normalized energy spectral densities of responses of hot-wire systems to various perturbations can be used to determine the frequency responses and cut-off frequencies of the systems. Based on this finding, a new procedure is proposed to experimentally determine the frequency response and approximately estimate the cut-off frequency of the hot-wire systems. The frequency responses of hot-wire systems determined from square wave perturbations show the hot-wire attenuation below the cut-off frequency. This offers opportunities of possible experimental determination of this attenuation, which so far has been out of reach and denied the possibility of correcting its effects in turbulence measurements. The effects of this attenuation on the experimental results of small-scale turbulence could be large.
Elastic strain and dopant activation in ion implanted strained Si nanowires

Strained Si nanowires (NWs) are attractive for deeply-scaled complementary metal-oxide-semiconductor devices due to the combination of enhanced carrier mobility and excellent electrostatic control as was demonstrated with trigate metal-oxide-semiconductor field effect transistors. The challenge in using strained Si NWs for devices is to preserve the elastic strain during the required processing steps. In this work we investigated the influence of fundamental processing steps like patterning and dopant ion implantation on the structural and transport properties of strained Si layers and NWs on silicon-on-insulator (SOI) substrates. NWs with widths down to 35 nm, fabricated on 25 nm strained SOI and implanted to doses ranging from 5×1014 to 2×1015 ions/cm2 were investigated. We show that strain conservation and a low sheet resistivity of 6.2×10−4 Ω cm, close to the layer resistivity, can only be obtained if the NWs are patterned on doped layers. For NWs directly implanted to doses above 1×1015 ions/cm2, com.
The Role of a Second Control Group in an Observational Study

An observational study is an attempt to estimate the effects of a treatment when subjects are not randomly assigned to treatment or control. The possibility of using more than one control group has often been briefly mentioned in general discussions of observational studies, and many obser- vational studies have used two control groups. Here, the limited and dispersed literature on this subject is reviewed, and the topic is developed in several directions by using a formal notation for observational studies. The value of a second control group depends on the supplementary infor- mation that is available about unobserved biases that are suspected to exist. A second control group provides a test of the assumption that conventional adjustments for observed covariates suffice in estimating treatment effects. Under the best of circumstances, this test is consistent and unbiased, and its power exceeds the probability of falsely detecting a treatment effect. Indeed, under the best of circumstances, two control groups can yield consistent and unbiased estimates of bounds on the treatment effect when conventional adjustments fail. In contrast, however, in the worst of circum- stances, a second control group can be of little value.
The Distribution of Dark Matter in the Coma Cluster

Limitations on positional and kinematical data for the distribution of dark matter in the Coma cluster are shown to cast doubt on any assumption of a constant M/L ratio. Attention is given to the possible forms of a smooth, spherical background potential (BP) for which positive phase space distribution functions that agree with available positions and radial velocities. Virial theorem, as applied to clusters of galaxies, assumes that galaxies and dark matter have similar distributions. The theorem can be used, together with complete velocity profiles calculated from velocity dispersion data, to constrain the distribution of dark matter. The constant M/L ratio then could be valid for the Coma cluster, provided subclustering or asymmetries in the galaxy distribution are negligible. 28 references.
Forward and inverse scattering from rough surfaces at low grazing incidence

In acoustic wave scattering from rough surfaces at low grazing angles the usual approximations are known to break down. In the forward‐scattering regime this case is often treated by the parabolic integral equation method. The scattering of plane waves within this formulation is considered, and effective reflection coefficients are derived for slightly rough surfaces. Of the higher‐order statistics, the dependence of the diffuse and specular components upon incident angle is also examined. The problem of surface reconstruction can be expressed in terms of coupled integral equations; it is explained how in the parabolic case these are easily treated. A major problem, however, is backscatter; a nonparabolic approach to this problem for low‐grazing angles is described. [Work supported by Smith Institute Research Fellowship. ]
Curve-Skeleton Extraction Using Appropriate Threshold Optimization

The curve-skeleton of an object is an important abstract geometrical and topological representation of its shape, which is extremely useful for pattern recognition and computer vision applications involving in shape analysis. In this paper, we propose an effective algorithm for extracting curve skeleton based on the definition and properties of curve skeleton from pixel cloud, which integrates the advantages of the visual main parts reliability for object recognition and the skeletons reduced-dimension for object representation. This algorithm can detect each pixel of the image, and find the salience value of each pixel; the salience value is the possibility of the pixel being a skeleton point. Then an appropriate threshold is selected to pruning the skeleton and to get the curve skeleton. In this way, the algorithm can be effective in reducing the number of non-skeleton pixels, and reduce the overall time of extracting skeleton. The experiments show that the skeleton keeps the topology of the target. And the corners of the skeleton are smoother and more natural. In additionally, it can effectively reduce redundant branches of skeleton.
Atomic‐scale wear properties of muscovite mica evaluated by scanning probe microscopy

Atomic‐scale wear properties of muscovite mica were evaluated in terms of friction force and surface topographic changes using a scanning probe microscope. Friction from a load of 100–300 nN generated a 1‐nm‐deep wear groove which corresponded to the depth from the surface of one cleavage plane to the surface of the next periodic cleavage plane. The atomic image of the bottom surface of the wear groove corresponds to the basal plane of mica.
Adaptive Seismic System for Detection of Moving Objects

Possibility of an estimation of coordinates of the seismic active object with use of methods of the high resolution considering a spatial orientation of geophones is investigated. It is shown that such approach provides detection of the pedestrian in radius not less than 50m. The adaptation proposed in the paper to changes of a sound velocity in a ground provides stability of operation of algorithm with the high resolution.
Local field energy density enhancement in planar metamaterials

We study local field energy density enhancement in planar metamaterials at normal incidence based on the finite element method. The microwave metamaterials composed of asymmetric resonators with/without quartz substrates are utilized to investigate the resonant response to incident electromagnetic waves. The trapped-mode resonant feature results from the excitation of an antisymmetric current mode due to the broken symmetry between two resonators and the quality factor and local field energy density enhancement strongly depend on the asymmetry. The proposed metamaterial on glass substrate shows the high possible quality factor of about 1000 and energy density enhance factor of up to 150000. To reduce losses of metamaterials further, freestanding metallic structure is considered being treated as perfect electric conductor and real-loss metal respectively. Real metallic metamaterial provides a very sharp trapped-mode resonance having the quality factor of up to 1500.
The transition from a TEM-like mode to a plasmonic mode in parallel-plate waveguides

We describe subwavelength-resolved measurements of the broadband terahertz field propagating inside a finite-width parallel-plate waveguide. We observe a transition in the spatial mode of the waveguide, in which the energy distribution shifts from the waveguide center to the edges with increasing frequency. This transition is surprisingly abrupt, and depends sensitively on the gap between the waveguide plates. These results may have important implications for a variety of terahertz experiments as well as in the design of optical systems and components in the visible and near-infrared regimes, which rely on plasmonic wave guiding.
Time-Dependent Density Functional Theory of Polarization Relaxation under External Field

A new inhomogeneous time-dependent density functional theory is proposed to study an effect of external field on the polarization relaxation of molecular liquids. The effect of external field is considered by the number density of solvent molecules, and the homogeneous approximation introduced by many previous studies is not employed. To demonstrate the validity of the theory, the spatial distribution of the relaxation time is calculated in a polar solvent system with an ion. The calculated results show a notable effect of translational diffusion on the spatial distribution of the polarization relaxation time.
Nanoscale defect clusters in metallic glasses

The reverse Monte Carlo method was used to obtain three-dimensional discrete distributions of constitutional atoms in melt-spun CuZr and CuZrTi metallic glasses from neutron and x-ray diffraction data. It was found that the icosahedral short-range order is less stable in the CuZr binary alloy than in the Ti-doped ternary alloy. The present investigation also provides evidence on the medium-range order, characterized by some nanoscale clusters of defects, in the metallic-glassy state.
Long-slit optical spectroscopy of emission-line nebulae in radio galaxies - The data

Results are presented on an extensive program of long-slit spectroscopy of the extended emission-line regions around 19 radio galaxies. Measurements, carried out at multiple position angles, were obtained with the Ritchey-Chretien spectrograph on NOAO's 4-m Mayall telescope at Kitt Peak. In general, no strong gradients in the H-alpha to the forbidden N II line were found within a source. In some sources, the gas appeared to be in rotation about the galaxy nucleus, with measured rotational velocities ranging from 100 to 325 km/sec. Frequently, the rotation curves appeared to be asymmetrically situated with respect to the nuclear line-emitting gas, showing offsets of about 60 km/sec, with respect to the nuclear gas. In other sources no evidence for rotation was found for the near nuclear emission-line gas, but the velocities of the gas farther out were positive on one side of the nucleus and negative on the other. 12 refs.
Mass Filtering Function of Magnetic Boundaries in Multi‐Cusp Ion Source

In a multi‐cusp ion source, magnetic boundaries, together with the difference between plasma potential and plasma chamber potential, functioned as a mass filter which filters out heavier ions in multi‐component plasmas. This method was applied to mixed inert gas plasmas and hydrogen plasmas and found to be very effective for general purposes which require to decrease unwanted heavier ions. Using this method to the ion source of iG4, target boron current above 80 mA and proton current above 120 mA were obtained.
Scaling of divertor conditions in ITER/NET with density, power, SOL transport, pitch, size, and particle throughput

Scaling laws for the divertor conditions to be expected in a next step device, ITER, are derived from 2D modelling. Model calculations are carried out for varying density, power, transport coefficients, pitch, size and particle throughput. In the low temperature, high recycling domain, the peak power, the electron temperature, and the particle density at the plate are found to be extremely sensitive to upstream parameters, especially to upstream density. Low density, high power operation therefore remains very demanding for the divertor. For operation at a critical density, for which the electron temperature at the point of peak power load is a fixed low value, the peak power load scales more gently, proportional to the power density flowing into the scrape-off layer. Precise control of the density is required to maintain this temperature
A Comparison Of The Number Of Rays Vs The Number Of Views In Reconstruction Tomography

In the field of x-ray reconstruction tomography, many sets of attenuation data are gathered at various angular orientations to the object. Each set of data is divided into many individual elements where each element represents a single pencil beam measurement of attenuated x-rays at some perpendicular distance from the origin. Given this scheme of data collection, it is reasonable to ask the following question: For a given reconstruction diameter, is it more important to collect more sets of projection data - views, or more elements per projection - rays? The answer to this question is basic to the design of computer assisted tomographic (CAT) scanners. Using simulated projection data, we show that for the case of Rotate/Translate geometry, the reconstructed picture is much more sensitive to rays than to views. That is, given the design choice between increasing the number of views or increasing the number of rays per view, one would clearly prefer to sample rays more frequently. This concept may be generalized to any geometry CAT scanner being particularly relevant in the design of pure rotational fan beam CAT scanners.
Dust in the Magellanic Clouds

Abstract The Magellanic Clouds are important templates for studying the role interstellar dust plays as actor and tracer of galaxy evolution. Due to their proximity, the Large and Small Magellanic clouds are uniquely suited to put detailed Galactic dust studies in a global context. With a metal abundance lower than that of the Sun, the Magellanic Clouds also permit to characterize interstellar matter composition and structure as a function of metallicity. The presentation of spectacular results from the AKARI and Spitzer surveys was one of the highlights of this Magellanic Clouds meeting. This paper puts these results in context. I discuss UV extinction and IR emission signatures of carbon and silicate dust. I present diverse evidence of dust processing in the ISM. I illustrate the correlation between the mm emission of dust, and gas column density using Milky Way surveys. I conclude with three main results. Dust in the SMC is not carbon poor. The composition of interstellar dust reflects its processing in interstellar space and thereby depends on local conditions and its past history. In the Magellanic Clouds, far-IR and sub-mm observations are indicating that there may be significantly more cold interstellar matter, cold H i and H2 gas, than estimated from H i and CO observations.
Disturbance attenuation and H/sub infinity /-control via measurement feedback in nonlinear systems

A solution to the problem of disturbance attenuation via measurement feedback with internal stability is presented for an affine nonlinear system. It is shown that the concept of disturbance attenuation, in the sense of truncated L/sub 2/ norms, can be given an interpretation in terms of the response to periodic inputs in the sense of RMS amplitude, even in the nonlinear setup. In the case of state feedback, a family of controllers is also provided. The proofs of all these results are simple and provide deeper insight even in the analysis of the corresponding linear control problem. >
The Compound Multinomial Distribution and Bayesian Analysis of Categorical Data from Finite Populations

Abstract A Bayesian analysis of the parameter vector, W (Wj = number of elements in category j), of a multivariate hypergeometric distribution is considered. It is shown that if, a priori, W is compound multinomial (CMtn), then, a posteriori, W is a translated CMtn. Many properties of the CMtn distribution are derived. These include joint moments of all orders; a characterization in terms of independent compound Poisson variables, conditional distribution of one subvector given another, and joint distributions of disjoint and overlapping sums of the components. It is shown that in applications related to analysis of variance and contingency tables, the parameters of interest are functions of W. A method is proposed for approximating the posterior distributions of such parameters, and a numerical example involving a performance index defined on a contingency table is presented.
Optical studies of the structure of porous silicon films formed in p-type degenerate and non-degenerate silicon

The detailed structure of porous Si (PS) layers formed in p-type wafers with resistivities 0.01-25 Omega cm has been investigated using reflectance, transmission, ellipsometry and photoluminescence techniques. Marked differences were observed in the optical properties of PS formed in degenerate or non-degenerate Si and these results are correlated with the results of other techniques. The optical techniques together with effective medium modelling have been shown to be useful non-destructive methods for either assessment of PS density or detection of unsuspected phases. The degenerate PS layers consistently showed good retention of the single-crystal characteristics of the starting wafer, only c-Si and voids being detected. For these samples, good agreement was obtained between optical and gravimetric densities. However, the non-degenerate PS had much greater variability, with greater loss of crystallinity and significant incorporation of oxygen, due to partial oxidation having occurred on or immediately after anodisation. Oxide fractions have been determined both optically and gravimetrically, with up to 50% oxide being detected in some samples. Non-degenerate PS samples with high oxygen concentrations appeared to be in the form of a chemical mixture, SiOx, from interpretation of the optical constants. Photoluminescence measurements together with the other techniques indicated a complex mixture of phases in the latter samples-voids, alpha -Si:O (and/or alpha -Si:H), an unknown amorphous phase and silicon oxide. This complex structure probably contributes to the observed instability of thick non-degenerate PS layers when heated in UHV as part of the cleaning procedure prior to epitaxial growth, all degenerate samples being able to withstand heat treatment.
JHK imaging of a field in Baade's window

A 256 × 256 Hg:Cd:Te array has been used to obtaine J, H, and K images of a field in Baade's Window. The data extend down to K∼16, which is near the base of the red giant branch at the distance of the Galactic bulge. The distribution of data points on the (K, J-K) and (J-H, H-K) diagrams is similar to that defined by previous aperture measurements. Furthermore, the redward edge of the data envelope on the (K, J-K) diagram roughly follows the giant branch of the cluster M67 to K∼15, indicating that the blanketing agent thought to dominate the broad-band photometric properties of super metal-rich stars must be present over a broad range of photospheric temperatures and surface gravities.