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

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

Условия образования минеральных включений в гидротермальных метасоматитах г. Двугорбой, Южная Камчатка

Mineralogical and geochemical features of hydrothermal metasomatites of the Southern Kamchatka were studied. The probable physico-chemical conditions of formation of the studied mineral inclusions in hydrothermally altered rocks are considered.Исследования гидротермальных метасоматитов выявили их минералогические и геохимические особенности. Рассмотрены вероятные физико-химические условия образования исследованных минеральных включений в гидротермально измененных породах

Selank and semax as potential hepatoprotectors in medical treatment of tuberculosis

The article notes that administering selank and semax to patients with tuberculosis would significantly reduce the number and severity of hepatotoxic reaction

ROLE OF PROGNOSTIC FACTORS IN THE DEVELOPMENT OF CENTRIC BREAST CANCER RECURRENCE

The purpose of the study was to define the factors influencing the development of a recurrence depending on the volume of surgical intervention and to investigate the possibility of performing organ-saving surgery (OSS) for centric breast cancer.The study used the clinical findings of 200 patients treated at the Department of Radiosurgery, N.N. Blokhin Russian Cancer Research Center in 1996 to 2006. According to the volume of surgical intervention, the patients were divided into 2 groups: 1) 106 patients who had undergone radical mastectomy; 2) 94 patients who had undergone radical resection. According to our data, the disease progressed in 32 (16%) cases. There were 12 local recurrences: in 8 (7.5%) and 4 (4.2%) cases after radical mastectomy and radical resection, respec- tively. The findings suggest that OSS may be performed after carefully patient selection, with all contraindications being kept in mind

Gradients of Taxonomic Diversity among Local Floras in the Russian Arctic

Latitudinal and longitudinal changes in taxonomic variables were analyzed in 319 local floras in the Russian Arctic. Within the studied segment of latitudinal gradient, most changes can be described in terms of linear regression with negative coefficients (a number of species, genera and families), or positive coefficients (a proportion of the leading families and genera). However, the mean number of species in a family or genus almost does not change with increasing latitude, although it slightly increases as one moves eastward. The proportion of monocots does not correlate with latitude, but slightly decreases as one moves eastward. Proportions of various families change asynchronously. Although correlation with longitude was less pronounced, mean species richness was specific to many subprovinces, even within a certain subzone. These differences reflect both the diversity of landscapes and the history of flora formation. Keywords: the Arctic, local floras, latitudinal and longitudinal gradient, floristic subprovince

СИНТЕЗ ПАРАУНИТАРНЫХ БАНКОВ ФИЛЬТРОВ В АЛГЕБРЕ КВАТЕРНИОНОВ ДЛЯ ВЫЧИСЛИТЕЛЬНЫХ СТРУКТУР С ФИКСИРОВАННОЙ ЗАПЯТОЙ

The synthesis method of paraunitary filter banks based on the quaternion algebra (Q-PUBF) for computing structures constrained by fixed point arithmetic is proposed. Synthesis problem using method of Lagrange multipliers is solved. It is shown that the Q-PUBF represents integer transform and can be used for image coding by scheme L2L (lossless-to-lossy).Предлагается метод синтеза параунитарных банков фильтров на основе алгебры кватернионов (Q-ПУБФ) для вычислительных структур с фиксированной запятой. Задача синтеза решается с помощью метода множителей Лагранжа. Показано, что Q-ПУБФ представляет собой целочисленное преобразование и может быть использовано для кодирования изображений по схеме L2L (lossless-to-lossy)

СИНТЕЗ FPGA-АРХИТЕКТУР БАНКОВ ФИЛЬТРОВ НА ОСНОВЕ БЛОЧНОЙ ЛЕСТНИЧНОЙ ФАКТОРИЗАЦИИ В АЛГЕБРЕ КВАТЕРНИОНОВ (ЧАСТЬ 1)

Nowadays the methodology for designing systems on a chip is based on highly parameterized IP components which provide a wide range of adjustment of costs in resources, fixed point arithmetic data formats and system performance for a specific target application. The article presents a systematic approach for synthesizing FPGA architectures of integer reversible paraunitary filter banks in quaternion algebra (Int-Q-PUBB) for L2L (lossless-to-lossy) image transformed encoding. It is shown that the basic elementary transformation of the filter bank is the operation of quaternion multiplication (Q-MUL), the block-lifting factorization of which and the distributed arithmetic on the adder are the basis of the parametrizable Q-MUL IP-component.В настоящее время методологии проектирования систем на кристалле основываются на высокопараметризированных IP-компонентах (IP – intellectual property), которые для конкретного целевого приложения обеспечивают широкий диапазон регулировки затрат ресурсов, форматов данных арифметики с фиксированной запятой и производительности системы. В статье представлен систематический подход к синтезу FPGA-архитектур целочисленных обратимых параунитарных банков фильтров в алгебре кватернионов (Int-Q-ПУБФ) для трансформационного кодирования изображений по схеме L2L (lossless-to-lossy). Показывается, что базовым элементарным преобразованием банка фильтров является операция умножения кватернионов (Q-MUL). Блочная лестничная факторизация данной операции и распределенная арифметика на сумматорах положены в основу параметризируемого Q-MUL IP-компонента

The Conditions of Opal Formation within the NorthMutnovskaya Volcanic Zone of Kamchatka

Выявлены параметры образования вмещающих пород опаловой минерализации. Установлены тип метасоматоза измененных пород и его направленность. Выявлены минеральные включения в опалах, указывающие на металлоносность Мутновской гидротермальной системы. Рассмотрен вероятный механизм образования опалов Северо-Мутновской зоны, проведено сопоставление по ряду характеристик с опалами месторождения Радужное, Приморье.The characteristics of formation of the opal mineralization in the host rock within Mutnovskaya volcanic zone were studied. The type of metasomatic rock alteration and its consecutive order were established. The results of study allowed identifying the mineral inclusions in opals, which was linked to the metalliferousness of the Mutnovsky hydrothermal system. Probable mechanism of opals formation within the North Mutnovskaya zone is considered, and its characteristics are compared to those from the opal field Raduzhnoye, Primorye