Coherence masking protection in brief noise complexes: Effects of temporal patterns

Three experiments examined listeners' thresholds for classifying the pitch of a target signal in a masking noise when it was presented alone as compared to when it was presented with a "cosignal." The target signal was a narrow band of noise centered on either 375 or 625 Hz and the masker was noise low-pass filtered at 1000 Hz. The cosignal provided no information about the pitch of the target signal but could potentially combine with it to form an auditory object; it was spectrally well separated from the target signal, consisting of a band of noise ranging from 2200 to 2900 Hz. Experiment 1 showed that identification thresholds were lower when the target signal was paired with the cosignal than when it was presented alone if the onsets and offsets of the target signal and cosignal were temporally synchronous. This is an instance of "coherence masking protection," a phenomenon that has previously been established in the perception of vowels [P.C. Gordon, Percept. Psychophys, 59, 232-242 (1997)]. The effect disappears when the cosignal leads and lags the target signal by short durations, a finding that also matches that observed previously with vowels. The finding that temporal relations between the components of a stimulus have similar effects on the perception of nonspeech noise complexes and speech sounds suggests that speech perception makes use of general auditory mechanisms for perceptual integration of this sort. Experiments 2 and 3 examine further the role of temporal relations between the onsets and offsets of the target signal and the cosignal in producing coherence masking protection. The results show that either onset synchrony or offset synchrony is sufficient to produce the effect when the cosignal is of greater duration than the target signal, but that only onset synchrony produces the effect when the target signal has greater duration than the cosignal. This pattern indicates that the target signal and cosignal do not contribute equally to the formation of auditory objects

System size dependence of strangeness production at 158 AGeV

Strange particle production in A+A interactions at 158 AGeV is studied by the CERN experiment NA49 as a function of system size and collision geometry. Yields of charged kaons, phi and Lambda are measured and compared to those of pions in central C+C, Si+Si and centrality-selected Pb+Pb reactions. An overall increase of relative strangeness production with the size of the system is observed which does not scale with the number of participants. Arguing that rescattering of secondaries plays a minor role in small systems the observed strangeness enhancement can be related to the space-time density of the primary nucleon-nucleon collisions.Comment: 5 pages, 3 figures, Presented at Quark Matter 2002, Nantes, Franc

Eye-Tracking and Corpus-Based Analyses of Syntax-Semantics Interactions in Complement Coercion

Previous work has shown that the difficulty associated with processing complex semantic expressions is reduced when the critical constituents appear in separate clauses as opposed to when they appear together in the same clause. We investigated this effect further, focusing in particular on complement coercion, in which an event-selecting verb (e.g., began) combines with a complement that represents an entity (e.g., began the memo). Experiment 1 compared reading times for coercion versus control expressions when the critical verb and complement appeared together in a subject-extracted relative clause (SRC) (e.g., The secretary that began/wrote the memo) compared to when they appeared together in a simple sentence. Readers spent more time processing coercion expressions than control expressions, replicating the typical coercion cost. In addition, readers spent less time processing the verb and complement in SRCs than in simple sentences; however, the magnitude of the coercion cost did not depend on sentence structure. In contrast, Experiment 2 showed that the coercion cost was reduced when the complement appeared as the head of an object-extracted relative clause (ORC) (e.g., The memo that the secretary began/wrote) compared to when the constituents appeared together in an SRC. Consistent with the eye-tracking results of Experiment 2, a corpus analysis showed that expressions requiring complement coercion are more frequent when the constituents are separated by the clause boundary of an ORC compared to when they are embedded together within an SRC. The results provide important information about the types of structural configurations that contribute to reduced difficulty with complex semantic expressions, as well as how these processing patterns are reflected in naturally occurring language

Print exposure modulates the effects of repetition priming during sentence reading

Individual readers vary greatly in the quality of their lexical representations, and consequently in how quickly and efficiently they can access orthographic and lexical knowledge. This variability may be explained, at least in part, by individual differences in exposure to printed language, because practice at reading promotes the development of stronger reading skills. In the present eyetracking experiment, we tested the hypothesis that the efficiency of word recognition during reading improves with increases in print exposure, by determining whether the magnitude of the repetition-priming effect is modulated by individual differences in scores on the author recognition test (ART). Lexical repetition of target words was manipulated across pairs of unrelated sentences that were presented on consecutive trials. The magnitude of the repetition effect was modulated by print exposure in early measures of processing, such that the magnitude of the effect was inversely related to scores on the ART. The results showed that low levels of print exposure, and thus lower-quality lexical representations, are associated with high levels of difficulty recognizing words, and thus with the greatest room to benefit from repetition. Furthermore, the interaction between scores on the ART and repetition suggests that print exposure is not simply an index of general reading speed, but rather that higher levels of print exposure are associated with an enhanced ability to access lexical knowledge and recognize words during reading

Canada, the G8 and the G20: A Canadian Approach to Shaping Global Governance in a Shifting International Environment

This paper reviews the history of the Group of Eight (G8) and the subsequent establishment of the Group of Twenty (G20).  It summarizes and analyzes the outcome of the most recent G8 and G20 Summits held in 2010 at Huntsville and Toronto respectively.  It takes stock of the G8/G20 summit processes, noting the emerging trends with respect to the role of Government Leaders, summit management and summit effectiveness. The paper concludes with a series of recommendations for a Canadian approach to influencing the rapid changes in international decision-making manifested by recent G8 and G20 experience. Chief among these suggestions is that Canada should lead work on resolving the relationship between the G8 and the G20 with a view to consolidating the G20 as a fully functioning instrument of global governance

Electrophysiological Evidence for Reversed Lexical Repetition Effects in Language Processing

Effects of word repetition are extremely robust, but can these effects be modulated by discourse context? We examined this in an ERP experiment that tested coreferential processing (when two expressions refer to the same person) with repeated names. ERPs were measured to repeated names and pronoun controls in two conditions: (1) In the prominent condition the repeated name or pronoun coreferred with the subject of the preceding sentence and was therefore prominent in the preceding discourse (e.g., "John went to the store after John/he."); (2) in the nonprominent condition the repeated name or pronoun coreferred with a name that was embedded in a conjoined noun phrase, and was therefore nonprominent (e.g., "John and Mary went to the store after John/he."). Relative to the prominent condition, the nonprominent condition always contained two extra words (e.g., "and Mary"), and the repetition lag was therefore smaller in the prominent condition. Typically, effects of repetition are larger with smaller lags. Nevertheless, the amplitude of the N400 was reduced to a coreferentially repeated name when the antecedent was nonprominent as compared to when it was prominent. No such difference was observed for the pronoun controls. Because the N400 effect reflects difficulties in lexical integration, this shows that the difficulty of achieving coreference with a name increased with the prominence of the referent. This finding is the reverse of repetition lag effects on N400 previously found with word lists, and shows that language context can override general memory mechanisms

Towards Error Handling in a DSL for Robot Assembly Tasks

This work-in-progress paper presents our work with a domain specific language (DSL) for tackling the issue of programming robots for small-sized batch production. We observe that as the complexity of assembly increases so does the likelihood of errors, and these errors need to be addressed. Nevertheless, it is essential that programming and setting up the assembly remains fast, allows quick changeovers, easy adjustments and reconfigurations. In this paper we present an initial design and implementation of extending an existing DSL for assembly operations with error specification, error handling and advanced move commands incorporating error tolerance. The DSL is used as part of a framework that aims at tackling uncertainties through a probabilistic approach.Comment: Presented at DSLRob 2014 (arXiv:cs/1411.7148

Deep Well Pump Seal

Lifewater International, a Christian non-profit, trains locals to repair water well hand pumps in various third world countries. It would be beneficial to retrofit difficult-to-repair hand pumps with a locally-made pump cylinder such as HydroMission\u27s SlapShot . The majority of the components in the SlapShot can be easily obtained in rural third world villages. However, the thick leather gaskets required to seal the water cylinder during the pumping operation are imported. These thick leather gaskets are expensive, and when they fail, this results in pumps being out of commission for extended periods of time. Lifewater has presented this problem to a team of three undergraduate mechanical engineering students at California Polytechnic State University, San Luis Obispo with the goal of being able to locally source and manufacture an adequate seal to replace the current thick leather seal

Books

Ask the Doctor. Hypertension By Vincent Friedewald. Pp. xiv + 120. R59.95. Kansas City:Andrews and McMeel. ISBN 0-8362-7022-3.How to Survive in Anaesthesia*By P Neville Robinson and George M Hall. Pp. xi + 172. £22.00.1997. London: BMJ. ISBN 0-7279-1066-3.Epidemiology. A Manual for South Africa* Edited by J M Katzenellenbogen, G Joubert and S S Abdool Karim. Pp. 295. R120. 1997. Cape Town: Oxford University Press. ISBN 0-19-571308-7