897 research outputs found
Uses of the pitch-scaled harmonic filter in speech processing
The pitch-scaled harmonic filter (PSHF) is a technique for decomposing speech signals into their periodic and aperiodic constituents, during periods of phonation. In this paper, the use of the PSHF for speech analysis and processing tasks is described. The periodic component can be used as an estimate of the part attributable to voicing, and the aperiodic component can act as an estimate of that attributable to turbulence noise, i.e., from fricative, aspiration and plosive sources. Here we present the algorithm for separating the periodic and aperiodic components from the pitch-scaled Fourier transform of a short section of speech, and show how to derive signals suitable for time-series analysis and for spectral analysis. These components can then be processed in a manner appropriate to their source type, for instance, extracting zeros as well as poles from the aperiodic spectral envelope. A summary of tests on synthetic speech-like signals demonstrates the robustness of the PSHF's performance to perturbations from additive noise, jitter and shimmer. Examples are given of speech analysed in various ways: power spectrum, short-time power and short-time harmonics-to-noise ratio, linear prediction and mel-frequency cepstral coefficients. Besides being valuable for speech production and perception studies, the latter two analyses show potential for incorporation into speech coding and speech recognition systems. Further uses of the PSHF are revealing normally-obscured acoustic features, exploring interactions of turbulence-noise sources with voicing, and pre-processing speech to enhance subsequent operations
Platelet-collagen adhesion: evidence for participation of antigenically distinct entities.
Univalent antibody fragments prepared from a rabbit antiserum raised against whole human platelets completely inhibited adhesion of platelets to immobilized trimeric collagen in a defined, Mg2+-dependent, adhesion assay. An octylglucoside extract of whole platelets completely neutralized this antibody, and all neutralizing activity bound to immobilized wheat germ agglutinin. Further fractionation on concanavalin A gave rise to subfractions that each neutralized only partially at saturation, when tested against antibody concentrations that inhibit 50% of platelet-collagen adhesion. When tested against higher antibody concentrations that completely inhibited adhesion, each subfraction had no detectable neutralizing effect, although the combined subfractions neutralized completely. This and other evidence suggests that more than one platelet entity participates in platelet-collagen adhesion. Although distinct, they appear to play interdependent roles in a single adhesion process
The Benefits of Supplementing the Eighth Grade American History Curriculum with Historical and Realistic Fiction Novels
As the textbook remains the driving force of instructional methodology in the secondary history curriculum, student enthusiasm and achievement in the discipline continue to decline. Textbooks, which fail to tell the complete story of the American experience, are not just shortchanging history, they are ill-suited to the developmental requirements of the adolescent learner. Through personal classroom experience, literature review, and a one-year site-based study, the evidence compiled in this study endorses the integration of social studies trade books, in particular historical and realistic fiction novels, as a prescription for diminishing, if not turning around, the discouraging trend in middle school social studies
The effect of riser end geometry on gas-solid hydrodynamics in a CFB riser operating above fast fluidization regimes
Riser hydrodynamics are a function of the gas and solids flow rates as well as the exit geometry, particularly when operated above the upper transport velocity. This work compares the exit voidage for multiple geometries and two different Geldart class B solids: glass beads and coke. Geometries were changed by modifying the volume of an abrupt T-shaped exit above the lateral riser exit. This was accomplished by positioning a plunger at various heights above the exit from zero to 0.38 m. A correlation was developed for the exit voidage as a function of the noted length and the following hydrodynamic parameters: load ratio, density ratio, diameter ratio and Reynolds No. In addition to the correlation, 95% confidence intervals are noted
The Effects of Skill Acquisition in Youth Jobs on Future Work and Earnings
Many studies have examined the effects that working as a youth has on work in the future. This study examines the effects of skill acquisition in youth jobs on future work and earnings. Data from a longitudinal survey of youth between the ages of 12-17 when first interviewed and between the ages of 25-31 when reported working as an adult are used to estimate income and pay from the adult occupation, ratings of skills used in the adult occupation, and the probability of working as an adult. The results predict that working as a youth and gaining general skills as well as the cumulative number of hours worked as a youth prove to have positive and significant effects on almost all examined aspects of the future adult work experience
Introduction to Serials Cataloging with RDA
This one-day pre-conference workshop, presented by Steve Shadle at NASIG 2018, was based on an abridged version of the Serials Cooperative Cataloging Training Program (SCCTP) Basic Serials Cataloging Workshop.1 Two sections of the workshop materials were omitted in order to complete the workshop in one day: Module 5 - Describing Carriers and Content, and Module 9 - Identifying Appropriate Copy. Module 10 - Working with Copy, was covered briefly. The overall goal of the workshop was to enable participants to catalog a “straightforward” print serial resource and to be able to understand elements of a serials cataloging record. The workshop focused primarily on cataloging print serials
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