Effects of disfluencies,predictability, and utterance position on word form variation in English conversation

Function words, especially frequently occurring ones such as (the, that, and, and of), vary widely in pronunciation. Understanding this variation is essential both for cognitive modeling of lexical production and for computer speech recognition and synthesis. This study investigates which factors affect the forms of function words, especially whether they have a fuller pronunciation (e.g., thi, thaet, aend, inverted-v v) or a more reduced or lenited pronunciation (e.g., thax, thixt, n, ax). It is based on over 8000 occurrences of the ten most frequent English function words in a 4-h sample from conversations from the Switchboard corpus. Ordinary linear and logistic regression models were used to examine variation in the length of the words, in the form of their vowel (basic, full, or reduced), and whether final obstruents were present or not. For all these measures, after controlling for segmental context, rate of speech, and other important factors, there are strong independent effects that made high-frequency monosyllabic function words more likely to be longer or have a fuller form (1) when neighboring disfluencies (such as filled pauses uh and um) indicate that the speaker was encountering problems in planning the utterance; (2) when the word is unexpected, i.e., less predictable in context; (3) when the word is either utterance initial or utterance final. Looking at the phenomenon in a different way, frequent function words are more likely to be shorter and to have less-full forms in fluent speech, in predictable positions or multiword collocations, and utterance internally. Also considered are other factors such as sex (women are more likely to use fuller forms, even after controlling for rate of speech, for example), and some of the differences among the ten function words in their response to the factors.     

Infants use prosodically conditioned acoustic-phonetic cues to extract words from speech

The Headturn Preference Paradigm was used to examine infants' use of prosodically conditioned acoustic-phonetic cues to find words in speech. Twelve-month-olds were familiarized to one passage containing an intended target (e.g., toga from toga#lore) and one passage containing an unintended target (e.g., dogma from dog#maligns). Infants were tested on the familiarized intended word (e.g., toga), familiarized unintended word (e.g., dogma), and two unfamiliar words. Infants listened longer to familiar intended words than to familiar unintended or unfamiliar words, demonstrating their use of word-level prosodically conditioned cues to segment words from speech. Implications for models of developmental speech perception are discussed.     

Lessons on e+e− annihilation from simple chain emission models

The dearth of solvable models for e⁺e^? annihilation often reduces one to excessively qualitative considerations, leaving obvious dynamical questions open. We discuss here various aspects of chain-emission models that can be cast into solvable form. In such models the virtual photon decays into a link (a pion, for example) and some state (e.g., an off-shell vector meson) which decays by sequentially shedding further links.Topics include the scaling behavior in such models (including how it is broken near ω = 0), neutral/charged distributions, the effect of internal quantum numbers, and, in a particularly simple version of the model, the two-particle distributions. In particular, we show how a large neutral to charged energy ratio can arise. Finally, we discuss variants on such models arising from possible variety in the links of the chain, (i.e., multichannel effects and the nonlinear effects arising from the branching of a chain into chains.     

Two-Dilaton Theories in Two Dimensions from Dimensional Reduction

Dimensional reduction of generalized gravity theories or string theories generically yields dilaton fields in the lower-dimensional effective theory. Thus at the level of D=4 theories and cosmology, many models contain more than just one scalar field (e.g., inflaton, Higgs, quintessence). Our present work is restricted to two-dimensional gravity theories with only two dilatons which nevertheless allow a large class of physical applications. The notions of factorizability, simplicity and conformal simplicity, Einstein form, and Jordan form are the basis of an adequate classification. We show that practically all physically motivated models belong either to the class of factorizable simple theories (e.g., dimensionally reduced gravity, bosonic string) or to factorizable conformally simple theories (e.g., spherically reduced scalar-tensor theories). For these theories a first order formulation is constructed straightforwardly. As a consequence an absolute conservation law can be established.     

Editorial

More than 30 years of scientific endeavor have brought us from programming simple models to impressive simulations of dynamic systems. Lattice models like Potts, percolation, fuse, fiber bundle, and growth models, just to name a few, are the prototypes or godfathers of statistical mechanics. With the availability of more powerful tools it became possible to develop these models and apply them on complex topologies, finding important practical applications in socio-technological systems (e.g., opinion dynamics, traffic, communication networks) and to engineering problems (e.g., fracture phenomena, mass transport). In parallel, particle models evolved from a hand full of interacting discs to three dimensional multibillion particle simulations that successfully describe interesting fracture phenomena, granular flow, and even fluid flow for engineering applications. Prof. Dr. Hans Jürgen Herrmann has dedicated his professional life to this journey.     

Identification of walked-upon materials in auditory, kinesthetic, haptic, and audio-haptic conditions

Locomotion generates multisensory information about walked-upon objects. How perceptual systems use such information to get to know the environment remains unexplored. The ability to identify solid (e.g., marble) and aggregate (e.g., gravel) walked-upon materials was investigated in auditory, haptic or audio-haptic conditions, and in a kinesthetic condition where tactile information was perturbed with a vibromechanical noise. Overall, identification performance was better than chance in all experimental conditions and for both solids and the better identified aggregates. Despite large mechanical differences between the response of solids and aggregates to locomotion, for both material categories discrimination was at its worst in the auditory and kinesthetic conditions and at its best in the haptic and audio-haptic conditions. An analysis of the dominance of sensory information in the audio-haptic context supported a focus on the most accurate modality, haptics, but only for the identification of solid materials. When identifying aggregates, response biases appeared to produce a focus on the least accurate modality--kinesthesia. When walking on loose materials such as gravel, individuals do not perceive surfaces by focusing on the most accurate modality, but by focusing on the modality that would most promptly signal postural instabilities.     

Model-independent analysis of muon g(mu) - 2

We consider possible physics beyond the standard model that could account for the large recently reported [Muon g-2 Collaboration, H. N. Brown et al., Phys. Rev. Lett. 86, 2227 (2001)] effect in g(mu)-2. If the underlying theory can be treated perturbatively, then the only possibilities are models that contain particles that yield "direct" contributions, e.g., supersymmetric models, models with unexpectedly light leptoquarks, or with a rather exotic heavy vector boson. If the underlying theory involves strong interactions, as in technicolor models, then the discrepancy could be accounted for by a variety of mechanisms.     

Energy dissipation in gigahertz oscillators from multiwalled carbon nanotubes

Using atomistic models and molecular dynamics simulations, interlayer corrugation and resistant force in a biwalled carbon nanotube are shown to be strongly dependent upon the morphology combination of the bitube. Consequently, energy dissipation in a commensurate (e.g., armchair/armchair or zigzag/zigzag) bitube oscillator is found to be much larger than that in an incommensurate (e.g., zigzag/armchair) oscillator, resulting in a decay of oscillation amplitude within a few nanoseconds in the commensurate bitube and several tens of nanoseconds in the incommensurate bitube.     

Granular species segregation under vertical tapping: effects of size, density, friction, and shaking amplitude

We present extensive molecular dynamics simulations on species segregation in a granular mixture subject to vertical taps. We discuss how grain properties, e.g., size, density, friction, as well as shaking properties, e.g., amplitude and frequency, affect such a phenomenon. Both the Brazil nut effect (larger particles on the top, BN) and the reverse Brazil nut effect (larger particles on the bottom, RBN) are found and we derive the system comprehensive "segregation diagram" and the BN to RBN crossover line. We also discuss the role of friction and show that particles which differ only for their frictional properties segregate in states depending on the tapping acceleration and frequency.     

Footstep sounds synthesis: Design,implementation, and evaluation of foot–floor interactions,surface materials,shoe types,and walkers’ features

This paper presents a novel footstep sound synthesizer based on physical and physically inspired models coupled with additive synthesis and signals multiplication. Several types of foot–floor interactions are simulated (e.g., different types of steps in walking and running or the sliding of the foot on the floor). Moreover, different types of shoes and ground materials (solid, aggregate, liquid, and hybrids) are synthesized, along with the modeling of some anthropomorphic features of the walkers (i.e., body size and foot-length). The design choices underlying the proposed synthesis methods were made according to four main points: (i) auditory perceptual relevance, i.e., ecological validity; (ii) cartoonification approach; (iii) parametric temporal control; (iv) real-time utilization. Moreover, four types of control for the involved synthesis algorithms are discussed. Firstly, a control strategy is proposed in order to generate sequences of footstep sounds. Secondly, the design choices underlying the tuning of the synthesis parameters are illustrated. Thirdly, a control strategy is presented to provide footstep sounds designers and foley artists with a tool to create perceptually compelling sounds in an intuitive manner. Fourthly, control techniques are discussed for the interactive case in presence of different types of locomotion interfaces along with their differences with the non-interactive control when locomotion is passively simulated. Finally, four perceptual experiments successfully assessed the validity of the proposed techniques.     

A TOPSIS-Inspired Ranking Method Using Constrained Crowd Opinions for Urban Planning

Crowdsourcing has become an important tool for gathering knowledge for urban planning problems. The questions posted to the crowd for urban planning problems are quite different from the traditional crowdsourcing models. Unlike the traditional crowdsourcing models, due to the constraints among the multiple components (e.g., multiple locations of facilities) in a single question and non-availability of the defined option sets, aggregating of multiple diverse opinions that satisfy the constraints as well as finding the ranking of the crowd workers becomes challenging. Moreover, owing to the presence of the conflicting nature of features, the traditional ranking methods such as the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) cannot always be feasible as the optimal solutions in terms of multiple objectives cannot occur simultaneously for the conflicting cases (e.g., benefit and cost criteria) for urban planning problems. Therefore, in this work, a multi-objective approach is proposed to produce better compromised solutions in terms of conflicting features from the general crowd. In addition, the solutions are employed to obtain a proper ideal solution for ranking the crowd. The experimental results are validated using two constrained crowd opinion datasets for real-world urban planning problems and compared with the state-of-the-art TOPSIS models.     

Reversibility, heat dissipation, and the importance of the thermal environment in stochastic models of nonequilibrium steady states

We examine stochastic processes that are used to model nonequilibrium processes (e.g., pulling RNA or dragging colloids) and so deliberately violate detailed balance. We argue that by combining an information-theoretic measure of irreversibility with nonequilibrium work theorems, the thermal physics implied by abstract dynamics can be determined. This measure is bounded above by thermodynamic entropy production and so may quantify how well a stochastic dynamics models reality. We also use our findings to critique various modeling approaches and notions arising in steady-state thermodynamics.     

Assembly of full-spectrum k-distributions from a narrow-band database; effects of mixing gases, gases and nongray absorbing particles, and mixtures with nongray scatterers in nongray enclosures

Full-spectrum k-distributions provide great accuracy combined with outstanding numerical efficiency for the evaluation of radiative transfer in absorbing-emitting molecular gases, but they do have several shortcomings: (1) It is difficult to assemble k-distributions for gas mixtures from precalculated full-spectrum k-distributions of individual gas species (i.e., without calculating the mixture k-distribution directly from the HITRAN/HITEMP database), (2) it is impossible to assemble k-distributions for a gas mixed with nongray absorbing particles (such as soot) from gas-only full-spectrum k-distributions, and (3) like all global models, full-spectrum k-distributions cannot accommodate nongray scattering behavior and/or nongray wall reflectances. In the present paper we show how these restrictions can be relaxed by (1) assembling full-spectrum k-distributions for a gas mixture from a narrow-band k-distribution database created for individual gas species, (2) by assembling gas and nongray absorbing particle mixture full-spectrum k-distributions from the same narrow-band database, and finally (3) by showing how a group of part-spectrum k-distributions can be generated from the same database to accommodate nongray scattering and nongray walls.     

The relationship between naming reaction time and functional MRI parameters in Broca's area

We examined the correlation between behavioural reaction time and functional imaging parameters of the blood oxygenated level dependent (BOLD) response in Broca's Area during a word identification task, and whether the correlation [Magnetic Resonance Imaging 22 (2004) 451-455] varies as a function of four stimulus types: regular words (REGs) (e.g., hint), irregular words (IRRs) (e.g., pint), nonwords (NWs) (e.g., bint), and pseudohomophones (PHs) (e.g., pynt). Participants named letter strings aloud during a functional magnetic resonance imaging study. Naming reaction times were recorded during regular gaps in image acquisition, and BOLD parameters were extracted via a Tikhonov regularized BOLD analysis technique. The results revealed that only PH reaction times were correlated with BOLD width, providing evidence that Broca's area supports phonetic decoding accompanied with phonological lexical access. In addition, we advanced the development of equation-based models of cognitive behaviour and neurophysiology, whereby we showed that the relationship of mathematical independence that exists for predicting REG accuracy, given IRR and NW or PH naming accuracy, was present for naming reaction time, BOLD width, BOLD time to peak, and BOLD intensity. Therefore, we provide converging behavioural and neuroanatomical evidence for a mathematically independent relationship between sight vocabulary and phonetic decoding systems, consistent with a dual-route model of reading.     

High-frequency gravitational waves having large spectral densities and their electromagnetic response

Various cosmology models, brane oscillation scenarios, interaction of interstellar plasma with intense electromagnetic radiation, and even high-energy physics experiments （e.g., Large Hadron Collider （LHC）） all predict high frequency gravitational waves （HFGWs, i.e., high-energy gravitons） in the microwave band and higher frequency region, and some of them have large energy densities. Electromagnetic （EM） detection to such HFGWs would be suitable due to very high frequencies and large energy densities of the HFGWs. We review several typical EM detection schemes, i.e., inverse Gertsenshtein effect （G-effect）, coupling of the inverse G effect with a coherent EM wave, coupling of planar superconducting open cavity with a static magnetic field, cylindrical superconducting closed cavity, and the EM sychro-resonance system, and discuss related minimal detectable amplitudes and sensitivities. Furthermore, we give some new ideas and improvement ways enhancing the possibility of measuring the HFGWs. It is shown that there is still a large room for improvement for those schemes to approach and even reach up the requirement of detection of HFGWs expected by the cosmological models and high-energy astrophysical process.     

Sentential, lexical, and acoustic effects on the perception of word boundaries

This study investigates the effects of sentential context, lexical knowledge, and acoustic cues on the segmentation of connected speech. Listeners heard near-homophonous phrases (e.g., plmpaI for "plum pie" versus "plump eye") in isolation, in a sentential context, or in a lexically biasing context. The sentential context and the acoustic cues were piloted to provide strong versus mild support for one segmentation alternative (plum pie) or the other (plump eye). The lexically biasing context favored one segmentation or the other (e.g., skmpaI for "scum pie" versus *"scump eye," and lmpaI, for "lump eye" versus *"lum pie," with the asterisk denoting a lexically unacceptable parse). A forced-choice task, in which listeners indicated which of two words they thought they heard (e.g., "pie" or "eye"), revealed compensatory mechanisms between the sources of information. The effect of both sentential and lexical contexts on segmentation responses was larger when the acoustic cues were mild than when they were strong. Moreover, lexical effects were accompanied with a reduction in sensitivity to the acoustic cues. Sentential context only affected the listeners' response criterion. The results highlight the graded, interactive, and flexible nature of multicue segmentation, as well as functional differences between sentential and lexical contributions to this process.     

Are There Incongruent Ground States in 2D Edwards–Anderson Spin Glasses?

We present a detailed proof of a previously announced result [1] supporting the absence of multiple (incongruent) ground state pairs for 2D Edwards–Anderson spin glasses (with zero external field and, e.g., Gaussian couplings): if two ground state pairs (chosen from metastates with, e.g., periodic boundary conditions) on ℤ² are distinct, then the dual bonds where they differ form a single doubly-infinite, positive-density domain wall. It is an open problem to prove that such a situation cannot occur (or else to show – much less likely in our opinion – that it indeed does happen) in these models. Our proof involves an analysis of how (infinite-volume) ground states change as (finitely many) couplings vary, which leads us to a notion of zero-temperature excitation metastates, that may be of independent interest. Received: 3 December 2000/ Accepted: 30 April 2001     

Simple models for bifurcations creating horseshoes

We present a class of simple models for global bifurcations creating horseshoes. Some properties known for Hénon mappings are easily obtained for these models such as, e.g., the existence of nontrivial hyperbolic sets. Kneading sequences techniques allow us to exhibit explicit differences with the global bifurcation diagram for maps of the interval. Explicit examples displaying wild hyperbolic sets and infinitely many sinks are also given as an illustration of the simplicity of these models.     

Practical use of variational principles for modeling water waves

This paper describes a method for deriving approximate equations for irrotational water waves. The method is based on a ‘relaxed’ variational principle, i.e., on a Lagrangian involving as many variables as possible. This formulation is particularly suitable for the construction of approximate water wave models, since it allows more freedom while preserving a variational structure. The advantages of this relaxed formulation are illustrated with various examples in shallow and deep waters, as well as arbitrary depths. Using subordinate constraints (e.g., irrotationality or free surface impermeability) in various combinations, several model equations are derived, some being well-known, other being new. The models obtained are studied analytically and exact traveling wave solutions are constructed when possible.