Showing papers on "Naturalness published in 1995"

Measuring the naturalness of synthetic speech

Abstract: Even the highest quality synthetic speech generated by rule sounds unlike human speech. As the intelligibility of rule-based synthetic speech improves, and the number of applications for synthetic speech increases, the naturalness of synthetic speech will become an important factor in determining its use. In order to improve this aspect of the quality of synthetic speech it is necessary to have diagnostic tests that can measure naturalness. Currently, all of the available metrics for evaluating the acceptability of synthetic speech do not distinguish sufficiently between measuring overall acceptability (including naturalness) and simply measuring the ability of listeners to extract intelligible information from the signal. In this paper we propose a new methodology for measuring the naturalness of particular aspects of synthesized speech, independent of the intelligibility of the speech. Although naturalness is a multidimensional, subjective quality of speech, this methodology makes it possible to assess the separate contributions of prosodic, segmental, and source characteristics of the utterance. In two experiments, listeners reliably differentiated the naturalness of speech produced by two male talkers and two text-to-speech systems. Furthermore, they reliably differentiated between the two text-to-speech systems. The results of these experiments demonstrate that perception of naturalness is affected by information contained within the smallest part of speech, the glottal pulse, and by information contained within the prosodic structure of a syllable. These results show that this new methodology does provide a solid basis for measuring and diagnosing the naturalness of synthetic speech.

Naturalness and image quality : chroma and hue variation in color images of natural scenes

Abstract: The relation between perceptual image quality and naturalness was investigated by varying the colorfulness and hue of color images of natural scenes. These variations were created by digitizing the images, subsequently determining their color point distributions in the CIELUV color space and finally multiplying either the chroma value of the hue angle of each pixel by a constant. During the chroma/hue-angle transformation the lightness and hue-angle/chroma value of each pixel were kept constant. Ten subjects rated quality and naturalness on numerical scales. The results show that both quality and naturalness deteriorate as soon as hues start to deviate from the ones in the original image. Chroma variation affected the impression of quality and naturalness to a lesser extent than did hue variation. In general, a linear relation was found between image quality and naturalness. For chroma variation, however, a small but systematic deviation could be observed. This deviation reflects the subjects' preference for more colorful but, at the same time, somewhat unnatural images.

Naturalness and image quality: chroma and hue variation in color images of natural scenes

Abstract: The relation between perceptual image quality and naturalness was investigated by varying the colorfulness and hue of color images of natural scenes. These variations were created by digitizing the images, subsequently determining their color point distributions in the CIELUV color space and finally multiplying either the chroma value of the hue angle of each pixel by a constant. During the chroma/hue-angle transformation the lightness and hue-angle/chroma value of each pixel were kept constant. Ten subjects rated quality and naturalness on numerical scales. The results show that both quality and naturalness deteriorate as soon as hues start to deviate from the ones in the original image. Chroma variation affected the impression of quality and naturalness to a lesser extent than did hue variation. In general, a linear relation was found between image quality and naturalness. For chroma variation, however, a small but systematic deviation could be observed. This deviation reflects the subjects' preference for more colorful but, at the same time, somewhat unnatural images.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Naturalness Constraints in Supersymmetric Theories with Non-Universal Soft Terms

Abstract: In the absence of universality the naturalness upper limits on supersymmetric particle masses increase significantly. The superpartners of the two light generations can be much heavier than the weak scale without extreme fine-tunings; they can weigh up to about 900 GeV --- or even up to 5 TeV, if SU(5) universality is invoked. This supresses sparticle-mediated rare processes and consequently ameliorates the problem of supersymmetric flavor violations. On the other hand, even without universality, the gluino and stop remain below about 400 GeV while the charginos and neutralinos are likely to be accessible at LEP2.

A Repertory Grid Test of the Claim That Sense of Landscape Naturalness Is Specific to Culture

Abstract: Repertory grid technique was used to test the claim that sense of landscape naturalness is socially constructed and culturally relative, and the reverse claim that sense of landscape naturalness is underlain by universals of human thought. Participants made judgments of sameness and difference concerning elements in a standard landscape of nine elements. Sample groups represented three cultures at extremes along a continuum of ideology concerning human relations with nature: Euro-Canadian at one end, Vuntut Gwich'in and north Baffin Inuit at the other. Results were consistent with the universalist but not the relativist hypothesis. Although principal factors for the three culture samples differ slightly, a common factor is nested within the variation, and it corresponds to the Euro-Canadian construct (natural x man-made). The study has implications for environmental education and environmental planning.

Consequences of Low Energy Dynamical Supersymmetry Breaking

Abstract: Relatively simple models can be constructed in which supersymmetry is dynamically broken at energies of $10^5-10^7$ GeV. Models of this kind do not suffer from the naturalness and cosmological difficulties of conventional supergravity models, and make definite predictions for the spectrum of supersymmetric particle masses. Thus ``Renormalizable Visible Sector Models'' are a viable alternative to more conventional approaches. This talk mostly summarizes the results of a recent paper written with Michael Dine and Yuri Shirman.

Issues in the glottalic theory of Indo-European: The comparative method, typology and naturalness

Abstract: The Glottalic Theory of Proto-Indo-European, whereby the traditional voiced series of stops *b, *d, *g has been replaced by the ejectives *p’, *t’, *k’, has been argued for mainly on typological grounds. What I will try to show here is that since any proposed sound change must satisfy the condition of naturalness, every reconstructed segment or class of segments, no matter how typologically plausible, must be derivable in each daughter language in conformity with this fundamental principle. To illustrate this, I will present a case from Proto-Algonkian showing how both the comparative method and typological considerations are insufficient to help us choose whether should be reconstructed since these two factors are not necessarily determinative of naturalness.

Effective couplings and Perturbative Unification

Abstract: In this paper we study the influence of the threshold effects due to massive degrees of freedom in the evolution with scale of gauge coupling constants. We first describe in detail the (standard) mass dependent renormalization prescription we use. This guides us to introduce and work with effective couplings, which are finite, process independent, and include complete threshold effects. We compute the evolution of the effective couplings in both, the Standard Model and its Minimal Supersymmetric extension, from \mz\ to the high energy region. We find that the effects from thresholds due to the standard massive gauge bosons are non--negligible, contrary to what is generally assumed when using other, less--accurate, descriptions of the thresholds, as for example in the step--function approximation. Moreover, we find that thresholds are relevant when studying perturbative SUSY unification, changing the conclusions reached when using the step--function approach. We find that threshold effects bring conflict between the known experimental data at $m_Z$, the naturalness upper bound on the masses of SUSY partners and the $perturbative$ unification of couplings.

Naturalness in a high-level synthetic speech system

Abstract: Naturalness in synthetic speech is to a large extent determined by how well the system models the variability found in human speech. Good models of variability are now emerging, and this paper describes how variability of several different types is incorporated into SPRUCE — a high level text-to-speech synthesis system. The synthesiser is carefully engineered according to the requirements of a recent computational model of speech production. The resulting voice output illustrates the usefulness of well motivated theory in speech synthesiser design.