MintHint: Automated Synthesis of Repair Hints

Being able to automatically repair programs is an extremely challenging task. In this paper, we present MintHint, a novel technique for program repair that is a departure from most of today's approaches. Instead of trying to fully automate program repair, which is often an unachievable goal, MintHint performs statistical correlation analysis to identify expressions that are likely to occur in the repaired code and generates, using pattern-matching based synthesis, repair hints from these expressions. Intuitively, these hints suggest how to rectify a faulty statement and help developers find a complete, actual repair. MintHint can address a variety of common faults, including incorrect, spurious, and missing expressions. We present a user study that shows that developers' productivity can improve manyfold with the use of repair hints generated by MintHint -- compared to having only traditional fault localization information. We also apply MintHint to several faults of a widely used Unix utility program to further assess the effectiveness of the approach. Our results show that MintHint performs well even in situations where (1) the repair space searched does not contain the exact repair, and (2) the operational specification obtained from the test cases for repair is incomplete or even imprecise

Artificial Aurora Produced by HAARP

We present results from the ionospheric heating experiment conducted at the HighFrequency Active Auroral Research Program (HAARP) facility, Alaska, on 12 March 2013. During theexperiment, HAARP transmitted in the direction of the magnetic zenith X-mode 4.57-MHz wave. Thetransmitted power was modulated with the frequency of 0.9 mHz, and it was pointed on a 20-km spot at thealtitude of 120 km. The heating (1) generates disturbances in the magnetic field detected with the fluxgatemagnetometer on the ground and (2) produces bright luminous spots in the ionosphere, observed with theHAARP telescope. Numerical simulations of the 3-D reduced magnetohydrodynamic (MHD) model revealthat these effects can be related to the magnetic field-aligned currents, excited in the ionosphere bychanging the conductivity in theEregion when the large-scale electric field exists in the heating region

Research on Geometrical Errors of Geokhod Prototype Shell Based on Coordinate Control Data

The article contains results of a research on geometric accuracy of a geokhod prototype shell. The article outlines the general structural features of geokhod bodies, and the main principles of manufacturing in test production. An overview of approaches to modeling of shell error occurrence is given. The researches were conducted on the basis of data obtained by coordinate control over the stabilizing section shell. The data were studied by statistical methods and analyzed in terms of their compliance with previously proposed mathematical models of formation of geokhod shell inaccuracies. It is shown that available mathematical models can not completely explain the origin of all the errors. The authors attribute unexplained geokhod shell errors as deformations caused by welding

Statistical Reconstruction of Qutrits

We discuss a procedure of measurement followed by the reproduction of the quantum state of a three-level optical system - a frequency- and spatially degenerate two-photon field. The method of statistical estimation of the quantum state based on solving the likelihood equation and analyzing the statistical properties of the obtained estimates is developed. Using the root approach of estimating quantum states, the initial two-photon state vector is reproduced from the measured fourth moments in the field . The developed approach applied to quantum states reconstruction is based on the amplitudes of mutually complementary processes. Classical algorithm of statistical estimation based on the Fisher information matrix is generalized to the case of quantum systems obeying Bohr's complementarity principle. It has been experimentally proved that biphoton-qutrit states can be reconstructed with the fidelity of 0.995-0.999 and higher.Comment: Submitted to Physical Review

The Simulation of the Trend of the Time Series in the form of the Spline of Third-Order With a Random Number of Data at the Moments of Measurement

The possibility of simulation of trend of a time series as a spline of third-order with a random number of data at the moments of measurement is discussed. Estimations of coefficients of the spline are obtained in the explicit form. The statistical characteristics of the received estimations are studied in details

Generalisation and maintenance across word classes : comparing the efficacy of two anomia treatments in improving verb naming

BACKGROUND : Many language treatments have been developed to remediate anomia, a debilitating and pervasive symptom of aphasia. The two major types of anomia treatments, semantic and phonological, have been shown to improve spoken production of trained words. However, generalisation to untrained words has been considerably variable and few studies have examined the improvement of untrained words from a different word class despite the presence of unbalanced noun-verb impairments in the majority of people with aphasia. AIM : This retrospective study investigated within and between treatment group effects of two anomia treatments (Semantic Feature Analysis, SFA, and Phonomotor Treatment, PMT) on naming of untrained verbs. METHODS AND PROCEDURES : The data for this study were retrospectively analysed from a randomised controlled trial with 57 persons with aphasia randomised to one of two treatment groups. Each participant received 56–60 hours of intensively delivered treatment over 6 weeks, with testing before, immediately after, and three months after treatment termination. OUTCOMES AND RESULTS : There was no significant between-group difference on confrontation naming of untrained verbs immediately post-treatment or three months following treatment termination (maintenance). Significant within-group findings were evident immediately post-treatment for the individuals in the SFA group and at maintenance for the PMT group. CONCLUSIONS : Our results show that neither SFA nor PMT was superior at inducing generalisation effects across word class (i.e. from nouns to verbs). These findings were consistent with the between-group results from the larger randomised controlled trial from which these data are analysed (Kendall, Oelke, Allen, Torrence, & Nadeau, 2018) in that there was no between-group difference in generalization to untrained words that do not share semantic or phonological sequence features. However, the within-treatment group results in the maintenance phase add to evidence from prior studies that Phonomotor Treatment is more likely to facilitate generalisation. Although generalisation to untrained stimuli was minimally maintained after SFA treatment, there was further improvement to untrained exemplars over time following Phonomotor Treatment.VA RR&D Merit Review Grant #C6572Rhttps://www.tandfonline.com/loi/paph20hj2020Speech-Language Pathology and Audiolog

Weak-Lensing by Large-Scale Structure and the Polarization Properties of Distant Radio-Sources

We estimate the effects of weak lensing by large-scale density inhomogeneities and long-wavelength gravitational waves upon the polarization properties of electromagnetic radiation as it propagates from cosmologically distant sources. Scalar (density) fluctuations do not rotate neither the plane of polarization of the electromagnetic radiation nor the source image. They produce, however, an appreciable shear, which distorts the image shape, leading to an apparent rotation of the image orientation relative to its plane of polarization. In sources with large ellipticity the apparent rotation is rather small, of the order (in radians) of the dimensionless shear. The effect is larger at smaller source eccentricity. A shear of 1% can induce apparent rotations of around 5 degrees in radio sources with the smallest eccentricity among those with a significant degree of integrated linear polarization. We discuss the possibility that weak lensing by shear with rms value around or below 5% may be the cause for the dispersion in the direction of integrated linear polarization of cosmologically distant radio sources away from the perpendicular to their major axis, as expected from models for their magnetic fields. A rms shear larger than 5% would be incompatible with the observed correlation between polarization properties and source orientation in distant radio galaxies and quasars. Gravity waves do rotate both the plane of polarization as well as the source image. Their weak lensing effects, however, are negligible.Comment: 23 pages, 2 eps figures, Aastex 4.0 macros. Final version, as accepted by ApJ. Additional references and some changes in the introduction and conclusion

Linear Relaxation Processes Governed by Fractional Symmetric Kinetic Equations

We get fractional symmetric Fokker - Planck and Einstein - Smoluchowski kinetic equations, which describe evolution of the systems influenced by stochastic forces distributed with stable probability laws. These equations generalize known kinetic equations of the Brownian motion theory and contain symmetric fractional derivatives over velocity and space, respectively. With the help of these equations we study analytically the processes of linear relaxation in a force - free case and for linear oscillator. For a weakly damped oscillator we also get kinetic equation for the distribution in slow variables. Linear relaxation processes are also studied numerically by solving corresponding Langevin equations with the source which is a discrete - time approximation to a white Levy noise. Numerical and analytical results agree quantitatively.Comment: 30 pages, LaTeX, 13 figures PostScrip

Evaluation of elastic and adhesive properties of solids by depth-sensing indentation

To describe properly interactions between contacting solids at micro/nanometre scales, one needs to know both adhesive and mechanical properties of the solids. Borodich and Galanov have introduced an effective method (the BG method) for identifying both characteristics from a single experiment on depth-sensing indentation by a spherical indenter using optimal fitting of the experimental data. Unlike traditional indentation techniques involving sharp indenters, the Borodich-Galanov methodology intrinsically takes adhesion into account. It is essentially a non-destructive approach. These features extend the scope of the method to important applications beyond the capabilities of conventional indentation. The scope of the original BG method was limited to the classic JKR and DMT theories. Recently, this restriction has been overcome by introducing the extended BG (eBG) method, where a new objective functional based on the concept of orthogonal distance curve fitting has been introduced. In the present work, questions related to theoretical development of the eBG method are discussed. Using the data for elastic bulk samples, it is shown that the eBG method is at least as good as the original BG method. It is shown that the eBG can be applied to adhesive indentation of coated, multilayered, functionally graded media

Foundations of Relational Particle Dynamics

Relational particle dynamics include the dynamics of pure shape and cases in which absolute scale or absolute rotation are additionally meaningful. These are interesting as regards the absolute versus relative motion debate as well as discussion of conceptual issues connected with the problem of time in quantum gravity. In spatial dimension 1 and 2 the relative configuration spaces of shapes are n-spheres and complex projective spaces, from which knowledge I construct natural mechanics on these spaces. I also show that these coincide with Barbour's indirectly-constructed relational dynamics by performing a full reduction on the latter. Then the identification of the configuration spaces as n-spheres and complex projective spaces, for which spaces much mathematics is available, significantly advances the understanding of Barbour's relational theory in spatial dimensions 1 and 2. I also provide the parallel study of a new theory for which positon and scale are purely relative but orientation is absolute. The configuration space for this is an n-sphere regardless of the spatial dimension, which renders this theory a more tractable arena for investigation of implications of scale invariance than Barbour's theory itself.Comment: Minor typos corrected; references update