Modeling Effects of Rhythmic Context on Perceived Duration: A Comparison of Interval and Entrainment Approaches to Short-Interval Timing.

Relative merits of interval and entrainment conceptions of the internal clock were assessed within a common theoretical framework by 4 time-judgment experiments. The timing of tone onsets marking the beginning and ending of standard and comparison time intervals relative to a context rhythm were manipulated: onsets were on time, early, or late relative to the implied rhythm, and 2 distinct accuracy patterns emerged. A quadratic ending profile indicated best performance when the standard ended on time and worst performance when it was early or late, whereas a flat beginning profile (Experiments 1-3) indicated uniform performance for the 3 expectancy conditions. Only in Experiment 4, in which deviations from expected onset times were large, did significant effects of beginning times appear in time-discrimination thresholds and points of subjective equality. Findings are discussed in the context of theoretical assumptions about clock resetting, the representation of time, and independence of successive time intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Subsecond thermophysics research at the Boris Kidrich Institute Vincha

In the early eighties, at the Boris Kidrich Institute Vincha, a method for measuring specific heat and electrical resistivity of electrical conductors in the millisecond resolution range was developed for measurements from room temperature to 1900 K. Over a period of nearly 10 years, the method was applied to different materials, including pure metals, ferrous, and nickel/ chromium alloys, and to the characterization of candidate materials for thermophysical property reference standards. This paper describes the method and reviews the results obtained in specific heat and electrical resistivity studies of ferromagnetic and other materials. The paper also demonstrates capabilities of the method for describing phase transitions or anomalies in pure metals (Fe, Co, Ni) or alloys (Nichrome, austenitic stainless steel).Paper presented at the Second Workshop on Subsecond Thermophysics, September 20–21, 1990, Torino, Italy.     

Application of substituted N-arylpyrroles in the corrosion protection of aluminium in hydrochloric acid

The inhibiting action of N-arylpyrroles on aluminium in 0.17 mol dm^–3 hydrochloric acid solution, in the temperature range 20–60 °C, was studied using potentiodynamic and electrochemical impedence spectroscopy techniques. The inhibiting efficiency of both investigated compounds 1-(2-fluorophenyl)-2,5-dimethylpyrrole (compound A) and 1-(2-fluorophenyl)-2,5-dimethylpyrrole-3-carbaldehyde (compound B) slightly increases with increasing temperature of the corrosive solution. Inhibitor adsorption on the elecrode surface decreases the apparent activation energy of the hydrogen evolution reaction. Compound A follows the Temkin adsorption isotherm, while its carbaldehyde derivative follows the Langmuir isotherm. The results of the apparent energy of activation and the standard free energy of adsorption point to stronger chemisorption of the compound A. However, due to additional condensation of molecules with carbaldehyde groups on the electrode surface, the carbaldehyde derivative exhibits even better inhibiting efficiency than compound A. The kinetic corrosion parameters, analysed in terms of the impedance data, show a satisfactory agreement with those obtained by the potentiodynamic method.     

On some interval methods for algebraic,exponential and trigonometric polynomials

New inclusion methods for the simultaneous determination of the zeros of algebraic, exponential and trigonometric polynomials are presented. These methods are realized in real interval arithmetic and do not use any derivatives. Using Weierstrass' correction some modified methods with the increased convergence rate are constructed. Convergence analysis and numerical example are included.     

An approach to emulating separable graphs

A technique foremulating multicomputer interconnection networks that are based onseparable graphs (graphs having bounded degree and sublinear multicolor recursive bisectors) is presented. Efficient emulations among interconnection networks are necessary for porting programs designed for one network to another.Emulations are formalized asgraph embeddings, where the nodes (processors) of theguest graph (emulated network) are assigned to nodes of thehost graph (emulator), while the edges (communication links) of the guest are routed via paths in the host. The communication slowdown in an emulation depens on thedilation (length of the longest routing path) and thecongestion (number of paths that contend for a host edge) of the embedding. Theexpansion of the embedding (the ratio of the sizes of the host to guest) determines the inefficiency of processor utilization. Cell trees are introduced as interconnection networks whose special communication properties enable them to serve as intermediate devices in these emulations. Nodes in cell trees are organized into equinumerous parts calledcells; the cells are labeled by nodes of a complete binary tree. Communication in cell trees is restricted to two specific and distinct primitives:cell communication is confined within cells, whiletransfer communication occurs between adjacent cells. Rather than solved directly, the emulation problem for the original guest-host pair is decomposed into two independent parts: emulating the guest by the cell tree, and emulating the cell tree by the host.In emulations of separable graphs by cell trees, the node assignment that ensures small dilation is derived from the separator-based decomposition of guest graphs. The congestion-free edge routing is achieved by coordinatingglobal andlocal phases, which are based on two characteristic cell-tree communication primitives.The technique is instantiated by emulating cell trees on specific host graphs. Withshuffle-like hypercube-derivative networks as hosts new constant-expansion emulations are obtained that have both dilation and congestion logarithmic in the size of the multicolor bisector of guest graphs. These emulations are the first such to have optimal (up to constants)congestion; they provide the firstoptimal algorithm for emulating arbitrary separable graphs on shuffle-like networks. The application of the technique tohypercubes as hosts also produces optimal emulations that differ from those previously known by having smaller expansion constants.This research was supported in part by NSF Grants CCR-88-12567 and CCR-90-13184, and by the University of Massachusetts Graduate School Fellowship for the academic year 1991-92. A preliminary version of this paper was presented at the 3rd ACM Symposium on Parallel Algorithms and Architectures, July 22–24, 1991, in Hilton Head, South Carolina, USA.     

Scientometric analysis of the research activities of chemists from the “Rugjer Bošković” Institute (Yugoslavia), 1976–1985

The research activity of chemists from the Rugjer Bokovi Institute (RBI, Zagreb, Yugoslavia) was analyzed for the period 1976–1985, covering 2018 research years of scientific work, and 1149 SCI registered papers (0.57 publications per research year). At the average, one paper was published by 3.05 scientists. The papers were published in 235 different journals, most frequently is the nationalCroatica Chemica Acta (171 papers). The publications were divided into two groups: for the periods 1976–1980 and 1981–1985, and for each paper citations were collected in the respective time period. An average publication had 2.58 citations. Chemical papers from the second period had 2.73 citations per paper, which is 85% of the expected value, and this was considerably more than for Yugoslav papers (66%) in general. The papers were classified according to the subfields used in theJournal Citation Reports, and the results compared with the data published bySchubert, Glänzel andBraun. The distribution of citations was also analyzed.     

Combining teacher-Led and technology-assisted instruction to improve phoneme blending to read words for elementary students with disabilities

Technology-assisted instruction has potential for helping students improve their reading skills. In the current studies, PowerPoint software was used to supplement teacher-led reading instruction for elementary-aged students with disabilities who struggled with phoneme blending to read words. The effectiveness of the intervention was assessed using two multiple probe design studies across sets of words based on an onset-rime (word family) strategy. In Study 1, teacher-led instruction was paired with technology-assisted instruction for all intervention sessions for three students in first and second grade. In Study 2, teacher-led instruction occurred between baseline and technology-assisted intervention sessions for three students in third and fourth grade. During the initial instruction sessions, participants recorded their own voices onto PowerPoint slides so that their technology-assisted instruction included self-modelling. Results of both studies indicated that technology-assisted instruction can be effective for helping students learn how to blend phonemes to read words; however, performance varied and there were limitations in each study that should be addressed in future research. Relevant implications for classroom instruction are emphasized.     

Frequency dependence of the spin-fluctuation spectrum in Pd: Calculations within the finite bandwidth model

The frequency dependence of the electron-paramagnon spectrumP() in Pd is calculated within the finite bandwidth model. It is found that for an almost full band, the magnitude, the range, and the position of the peak frequency inP() are dramatically reduced compared to their values in the usual paramagnon theory. Also, we find that the frequency dependence of the spin-fluctuation contribution to the electron self-energy is strongly affected by a close proximity of the Fermi level to the top of the band. We speculate that an unusually large value of the Coulomb pseudopotential is probably partially responsible for the absence of superconductivity in Pd.