AN EFFICIENT SPEECH GENERATIVE MODEL BASED ON DETERMINISTIC/STOCHASTIC SEPARATION OF SPECTRAL ENVELOPES

The paper presents a speech generative model that provides an efficient way of generating speech waveform from its amplitude spectral envelopes. The model is based on hybrid speech representation that includes deterministic (harmonic) and stochastic (noise) components. The main idea behind the approach originates from the fact that speech signal has a determined spectral structure that is statistically bound with deterministic/stochastic energy distribution in the spectrum. The performance of the model is evaluated using an experimental low-bitrate wide-band speech coder. The quality of reconstructed speech is evaluated using objective and subjective methods. Two objective quality characteristics were calculated: Modified Bark Spectral Distortion (MBSD) and Perceptual Evaluation of Speech Quality (PESQ). Narrow-band and wide-band versions of the proposed solution were compared with MELP (Mixed Excitation Linear Prediction) speech coder and AMR (Adaptive Multi-Rate) speech coder, respectively. The speech base of two female and two male speakers were used for testing. The performed tests show that overall performance of the proposed approach is speaker-dependent and it is better for male voices. Supposedly, this difference indicates the influence of pitch highness on separation accuracy. In that way, using the proposed approach in experimental speech compression system provides decent MBSD values and comparable PESQ values with AMR speech coder at 6,6 kbit/s. Additional subjective listening testsdemonstrate that the implemented coding system retains phonetic content and speaker’s identity. It proves consistency of the proposed approach.The paper presents a speech generative model that provides an efficient way of generating speech waveform from its amplitude spectral envelopes. The model is based on hybrid speech representation that includes deterministic (harmonic) and stochastic (noise) components. The main idea behind the approach originates from the fact that speech signal has a determined spectral structure that is statistically bound with deterministic/stochastic energy distribution in the spectrum. The performance of the model is evaluated using an experimental low-bitrate wide-band speech coder. The quality of reconstructed speech is evaluated using objective and subjective methods. Two objective quality characteristics were calculated: Modified Bark Spectral Distortion (MBSD) and Perceptual Evaluation of Speech Quality (PESQ). Narrow-band and wide-band versions of the proposed solution were compared with MELP (Mixed Excitation Linear Prediction) speech coder and AMR (Adaptive Multi-Rate) speech coder, respectively. The speech base of two female and two male speakers were used for testing. The performed tests show that overall performance of the proposed approach is speaker-dependent and it is better for male voices. Supposedly, this difference indicates the influence of pitch highness on separation accuracy. In that way, using the proposed approach in experimental speech compression system provides decent MBSD values and comparable PESQ values with AMR speech coder at 6,6 kbit/s. Additional subjective listening testsdemonstrate that the implemented coding system retains phonetic content and speaker’s identity. It proves consistency of the proposed approach

The Effect of Atmospheric Pollution on Building Materials in the Urban Environment

Nowadays atmospheric pollution affects not only the urban environment in general, but building materials, which leads to their corrosion, in particular. The article discusses the regularities of the adhesion process of particulate matter (dust) on the vertical surfaces of buildings and structures, which are made of various building materials. On the basis of experimental studies, regression dependences of the adhesion of urban dust on different vertical surfaces from random determining factors were obtained. Thus, by studying the regularities of pollution of urban environment objects, made of various building materials, it is possible to achieve their preservation, since they demonstrate the architectural and design features of various historical periods of the country's development

Damage buildup in Si under bombardment with MeV heavy atomic and molecular ions

Accumulation of structural disorder in Si bombarded at −196 °C with 0.5 MeV ²⁰⁹Bi₁ and 1 MeV ²⁰⁹Bi₂ ions (the so-called molecular effect) is studied by Rutherford backscattering/channeling spectrometry. Results show that the damage buildup is sigmodal even for such heavy-ion bombardment at liquid nitrogen temperature. This strongly suggests that, for the implant conditions of this study, the buildup of lattice damage cannot be considered as an accumulation of completely disordered regions. Instead, damage-dose curves are well described by a cascade-overlap model modified to take into account a catastrophic collapse of incompletely disordered regions into an amorphous phase after damage reaches some critical level. Results also show that Bi₂ ions produce more lattice damage than Bi₁ ions implanted to the same dose. The ratio of lattice disorder produced by Bi₂ and Bi₁ ions is 1.7 near the surface, decreases with depth, and finally becomes close to unity in the bulk defect peak region. Parameters of collision cascades obtained using ballistic calculations are in good agreement with experimental data. The molecular effect is attributed to a spatial overlap of (relatively dense) collision subcascades, which gives rise to (i) nonlinear energy spike processes and/or (ii) an increase in the defect clustering efficiency with an effective increase in the density of ion-beam-generated defects.Research at StPSTU was supported in part by the Ministry for General and Professional Education of the Russian Federation

Studies of the structure and functions of blood cells in senile patients with pneumonia on the biological model of hypoxia by scanning probe microscopy

Biological model of hypoxia can be used for the diagnosis of functional changes in human erythrocytes under the effect of the hypoxic factor. The use of this model together with modern methods of scanning probe microscopy for evaluation of the severity of pulmonological disease in senile patients will help to predict treatment efficiency and outcom

Russian-French Agreements of 1891-1893 in International Relations at Turn of 19th and 20th Centuries

The article is dedicated to Russia’s European policy from the formation of the German Empire in 1871 to the beginning of World War I. It examines the historical conditions, reasons, and nature of the Russo-French military-political alliance of 1891-1893. The role of Emperor Alexander III in the political rapprochement between Russia and France on an anti-German and anti-Austrian basis is demonstrated. The existence of mutual interest between Russia and France in forming a military-political alliance is revealed. The Bierk Treaty of 1905 between Emperors Wilhelm II and Nicholas II is analyzed, showing that this treaty fundamentally contradicted the development of military-political cooperation between Russia and France and therefore was not implemented. The conclusion is drawn regarding the significance of the Russo-French alliance of the early 1890s for the foreign policy and historical destiny of the Russian Empire. Germany's interest in strengthening its influence on the foreign policy of the Russian Empire is shown. It is proven that Germany’s attempts to attract Russia to its side did not succeed, and Russia maintained its alliance with France, which was more significant for it during the period under consideration, despite the fact that ultimately this alliance led to the involvement of the Russian Empire in a world war

THE NEED TO STUDY THE BASIS OF COPYRIGHT AND LICENSE BY STUDENTS OF DIRECTIONS RELATED TO THE DEVELOPMENT OF THE SOFTWARE

The article discusses the main reasons for students to study copyright information system software developers and understanding the difference between them.В статье рассматриваются основные причины необходимости изучения студентами разработчиками информационных систем авторское правое в сфере лицензирования программного обеспечения и понимание разницы между ними

Significance of Operative Legal Investigation as the Criterion of Reasonable Term Definition

The article is devoted to the problem of tardiness of criminal procedure which can lead to breaches of human rights self-dependently

Improving the University Digital Infrastructure Management System: Practice of Social Network Analysis

This article presents the results of applied research aimed at developing topical approaches to solving the problem of dysfunctionality of universities’ digital infrastructures in social media. In the context of the large-scale digitalization and networking processes of modern society, higher education institutions are faced with new challenges that threaten their further sustainability and reduce their competitiveness. As a possible solution to this problem, the authors propose a comprehensive study of university network structures in social media and further implementation of actual practices of online profile management and digital communities. By applying the method of social graphs and automated tools for processing open digital data, a universal algorithm for building and interpreting the resulting visual models is defined. The article substantiates the basic problems faced by modern universities in developing their own digital structures, as well as the ways to solve them, aimed at improving digital infrastructure management, establishing effective communication with target groups, consolidating the organizational structure, developing educational and scientific communities, and promoting the university brand. The proposed interactive digital maps have a high practical potential for direct implementation in the management process of the Russian universities

Fundamentos del enfoque de sistemas para la metodología de evaluación de instalaciones de obras acuáticas en medio natural

De acuerdo con los requisitos reglamentarios y ambientales sobre el funcionamiento de las instalaciones sanitarias denominadas objetos de actividad, se debe evaluar la influencia ambiental de estas instalaciones. en términos de utilización de los recursos hídricos, que es exactamente el objetivo de este estudio. Los fundamentos de la metodología de esta evaluación se desarrollan mediante el enfoque de sistema centrado en la noción de sistema. Los resultados del estudio de la interacción del objeto de actividad (OA) con los ambientes naturales (NENV) del geosistema de cuenca se utilizan en el desarrollo de los fundamentos de la metodología de evaluación de la influencia ambiental (EIA). Los resultados del estudio se han utilizado para diseñar y construir instalaciones de ingeniería hidroeléctrica en el norte del Cáucaso en el sur de Rusi

Instantaneous pitch estimation algorithm based on multirate sampling

The paper presents an algorithm for accurate pitch estimation that takes advantage of the sinusoidal model with instantaneous parameters. The algorithm decomposes the signal into subband components, extracts their instantaneous parameters and evaluates period candidate generating function (PCGF). In order to achieve high accuracy for low and high-pitched sounds it is assumed that possible pitch variation range is proportional to current pitch value. The bandwidths of the decomposition filters and length of the analysis frame are scaled for each period candidate by multirate sampling. The algorithm is compared to other widely used pitch extractors on artificial quasiperiodic signals and natural speech. The proposed algorithm shows a remarkable frequency and time resolution for pitch-modulated sounds and performs well both in clean and noisy conditions