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Journal Details
Format
Journal
eISSN
1335-8871
First Published
07 Mar 2008
Publication timeframe
6 times per year
Languages
English

Search

Volume 10 (2010): Issue 3 (June 2010)

Journal Details
Format
Journal
eISSN
1335-8871
First Published
07 Mar 2008
Publication timeframe
6 times per year
Languages
English

Search

6 Articles
Open Access

An Experiment with Evaluation of Emotional Speech Conversion by Spectrograms

Published Online: 16 Jun 2010
Page range: 72 - 77

Abstract

An Experiment with Evaluation of Emotional Speech Conversion by Spectrograms

The spectrogram is a useful tool for visual quality comparison of different types of emotional synthetic speech. This paper is focused on application of this method to evaluation of sentences after spectral and prosodic modifications for emotional speech conversion. Performed experiments with spectrogram evaluation for several male and female speakers and four emotional states (joy, sadness, anger, neutral state) are also described.

Keywords

  • emotional speech
  • spectrogram
  • periodogram
  • evaluation of synthetic speech
Open Access

Improvement of Traceability of Widely-Defined Measurements in the Field of Humanities

Published Online: 16 Jun 2010
Page range: 78 - 88

Abstract

Improvement of Traceability of Widely-Defined Measurements in the Field of Humanities

In the last decades, a tendency to extend the domain of "fuzzy" measurements of multiparametric quantities to the field of humanities has been observed. In the measurement process, the "fuzzy" measurements should meet the requirements of metrological traceability. The paper deals with the approach proposed for developing a measurement model of "fuzzy" measurements. The approach suggested is illustrated by an example of a model for measuring the emotions contained in musical fragments. The model is based on the hypothesis that permits to explain the origination of emotions in the evolution process.

Keywords

  • Traceability
  • multiparametric measurand
  • measurement model
  • music perception
  • infrasound
Open Access

Determination of Load Angle for Salient-pole Synchronous Machine

Published Online: 16 Jun 2010
Page range: 89 - 96

Abstract

Determination of Load Angle for Salient-pole Synchronous Machine

This paper presents two methods for load angle determination for salient-pole synchronous generator. The first method uses optical encoder to detect the rotor position. In some cases the end of the rotor shaft is not free to be used and mounting of an encoder is impossible. Therefore, the second method proposes estimation of the load angle based on the measured electrical values that have been already used in excitation control system of the synchronous generator. Estimation method uses corresponding voltage-current vector diagram and parameters of the synchronous generator, transformer and transmission lines. Both methods were experimentally verified on the digital control system and synchronous generator connected to power system. The estimation and measured results were compared. The accuracy of load angle estimation method depends on voltage and current measurement accuracy as well as generator, transformer and transmission line parameter accuracy. The estimation method gives satisfactory accuracy for load angles less than 120° el. Thus, it can be applied in excitation control system to provide stable work of synchronous generator in under-excitation operating area.

Keywords

  • Load angle measurement
  • load angle estimation
  • synchronous generator
Open Access

Measurement and Imaging of Planar Electromagnetic Phantoms Based on NMR Imaging Methods

Published Online: 16 Jun 2010
Page range: 97 - 101

Abstract

Measurement and Imaging of Planar Electromagnetic Phantoms Based on NMR Imaging Methods

Planar electromagnetic phantom design for measurement and imaging using NMR has been performed. Electromagnetic phantom computation and testing on a NMR 0.178 Tesla Esaote Opera imager were accomplished. The classical geometrical and chemical phantoms are generally used for testing of NMR imaging systems. They are simple cylindrical or rectangular objects with different dimensions and shapes with holes filled with specially prepared water solutions. In our experiments a homogeneous phantom (reference medium) - a container filled with water - was used. The resultant image represents the magnetic field distribution in the homogeneous phantom. An image acquired by this method is actually a projection of the sample properties onto the homogeneous phantom. The goal of the paper is to map and image the magnetic field deformation using NMR imaging methods. We are using a double slender rectangular vessel with constant thickness filled with specially prepared water solution in our experiments. For detection a carefully tailored gradient-echo imaging method, susceptible to magnetic field homogeneity, was used.

Keywords

  • Magnetic measurement
  • magnetic phantom
  • magnetic resonance imaging
  • quality testing
Open Access

Wavefront sensors for adaptive optical systems

Published Online: 16 Jun 2010
Page range: 102 - 107

Abstract

Wavefront sensors for adaptive optical systems

A high precision Shack-Hartmann wavefront (WF) sensor has been developed on the basis of a low-aperture off-axis diffraction lens array. The device is capable of measuring WF slopes at array sub-apertures of 640x640 μm in size with an error not exceeding 4.80 arcsec (0.15 pixel), which corresponds to the standard deviation equal to 0.017 λ at the reconstructed WF with wavelength λ. Also the modification of this sensor for adaptive system of solar telescope using extended scenes as tracking objects, such as sunspot, pores, solar granulation and limb, is presented.

The software package developed for the proposed WF sensors includes three algorithms of local WF slope estimation (modified centroids, normalized cross-correlation and fast Fourier-demodulation), as well as three methods of WF reconstruction (modal Zernike polynomial expansion, deformable mirror response function expansion and phase unwrapping), that can be selected during operation with accordance to the application.

Keywords

  • Wavefront sensor
  • solar and adaptive optics
  • turbulent atmosphere
Open Access

Iodine Molecules Differential Absorption Cross section Lidar Studies

Published Online: 16 Jun 2010
Page range: 108 - 110

Abstract

Iodine Molecules Differential Absorption Cross section Lidar Studies

Lidar monitoring of the gaseous molecules in atmosphere can be used for concentration measurements of the toxic pollutants in air of the urban and industrial regions. Such a concentration study in the multi-components gaseous mixture by lidar technique is a complex problem in atmospheric pollution monitoring. The differential absorption lidar (DA-lidar) is the most preferable for the detection of iodine molecules at very low concentration levels. The iodine molecules absorption cross section in the laboratory lidar studies and lidar equation simulation in this lidar variant corresponds with earlier data.

Keywords

  • iodine molecules
  • concentration
  • lidar
  • differential absorption cross section
6 Articles
Open Access

An Experiment with Evaluation of Emotional Speech Conversion by Spectrograms

Published Online: 16 Jun 2010
Page range: 72 - 77

Abstract

An Experiment with Evaluation of Emotional Speech Conversion by Spectrograms

The spectrogram is a useful tool for visual quality comparison of different types of emotional synthetic speech. This paper is focused on application of this method to evaluation of sentences after spectral and prosodic modifications for emotional speech conversion. Performed experiments with spectrogram evaluation for several male and female speakers and four emotional states (joy, sadness, anger, neutral state) are also described.

Keywords

  • emotional speech
  • spectrogram
  • periodogram
  • evaluation of synthetic speech
Open Access

Improvement of Traceability of Widely-Defined Measurements in the Field of Humanities

Published Online: 16 Jun 2010
Page range: 78 - 88

Abstract

Improvement of Traceability of Widely-Defined Measurements in the Field of Humanities

In the last decades, a tendency to extend the domain of "fuzzy" measurements of multiparametric quantities to the field of humanities has been observed. In the measurement process, the "fuzzy" measurements should meet the requirements of metrological traceability. The paper deals with the approach proposed for developing a measurement model of "fuzzy" measurements. The approach suggested is illustrated by an example of a model for measuring the emotions contained in musical fragments. The model is based on the hypothesis that permits to explain the origination of emotions in the evolution process.

Keywords

  • Traceability
  • multiparametric measurand
  • measurement model
  • music perception
  • infrasound
Open Access

Determination of Load Angle for Salient-pole Synchronous Machine

Published Online: 16 Jun 2010
Page range: 89 - 96

Abstract

Determination of Load Angle for Salient-pole Synchronous Machine

This paper presents two methods for load angle determination for salient-pole synchronous generator. The first method uses optical encoder to detect the rotor position. In some cases the end of the rotor shaft is not free to be used and mounting of an encoder is impossible. Therefore, the second method proposes estimation of the load angle based on the measured electrical values that have been already used in excitation control system of the synchronous generator. Estimation method uses corresponding voltage-current vector diagram and parameters of the synchronous generator, transformer and transmission lines. Both methods were experimentally verified on the digital control system and synchronous generator connected to power system. The estimation and measured results were compared. The accuracy of load angle estimation method depends on voltage and current measurement accuracy as well as generator, transformer and transmission line parameter accuracy. The estimation method gives satisfactory accuracy for load angles less than 120° el. Thus, it can be applied in excitation control system to provide stable work of synchronous generator in under-excitation operating area.

Keywords

  • Load angle measurement
  • load angle estimation
  • synchronous generator
Open Access

Measurement and Imaging of Planar Electromagnetic Phantoms Based on NMR Imaging Methods

Published Online: 16 Jun 2010
Page range: 97 - 101

Abstract

Measurement and Imaging of Planar Electromagnetic Phantoms Based on NMR Imaging Methods

Planar electromagnetic phantom design for measurement and imaging using NMR has been performed. Electromagnetic phantom computation and testing on a NMR 0.178 Tesla Esaote Opera imager were accomplished. The classical geometrical and chemical phantoms are generally used for testing of NMR imaging systems. They are simple cylindrical or rectangular objects with different dimensions and shapes with holes filled with specially prepared water solutions. In our experiments a homogeneous phantom (reference medium) - a container filled with water - was used. The resultant image represents the magnetic field distribution in the homogeneous phantom. An image acquired by this method is actually a projection of the sample properties onto the homogeneous phantom. The goal of the paper is to map and image the magnetic field deformation using NMR imaging methods. We are using a double slender rectangular vessel with constant thickness filled with specially prepared water solution in our experiments. For detection a carefully tailored gradient-echo imaging method, susceptible to magnetic field homogeneity, was used.

Keywords

  • Magnetic measurement
  • magnetic phantom
  • magnetic resonance imaging
  • quality testing
Open Access

Wavefront sensors for adaptive optical systems

Published Online: 16 Jun 2010
Page range: 102 - 107

Abstract

Wavefront sensors for adaptive optical systems

A high precision Shack-Hartmann wavefront (WF) sensor has been developed on the basis of a low-aperture off-axis diffraction lens array. The device is capable of measuring WF slopes at array sub-apertures of 640x640 μm in size with an error not exceeding 4.80 arcsec (0.15 pixel), which corresponds to the standard deviation equal to 0.017 λ at the reconstructed WF with wavelength λ. Also the modification of this sensor for adaptive system of solar telescope using extended scenes as tracking objects, such as sunspot, pores, solar granulation and limb, is presented.

The software package developed for the proposed WF sensors includes three algorithms of local WF slope estimation (modified centroids, normalized cross-correlation and fast Fourier-demodulation), as well as three methods of WF reconstruction (modal Zernike polynomial expansion, deformable mirror response function expansion and phase unwrapping), that can be selected during operation with accordance to the application.

Keywords

  • Wavefront sensor
  • solar and adaptive optics
  • turbulent atmosphere
Open Access

Iodine Molecules Differential Absorption Cross section Lidar Studies

Published Online: 16 Jun 2010
Page range: 108 - 110

Abstract

Iodine Molecules Differential Absorption Cross section Lidar Studies

Lidar monitoring of the gaseous molecules in atmosphere can be used for concentration measurements of the toxic pollutants in air of the urban and industrial regions. Such a concentration study in the multi-components gaseous mixture by lidar technique is a complex problem in atmospheric pollution monitoring. The differential absorption lidar (DA-lidar) is the most preferable for the detection of iodine molecules at very low concentration levels. The iodine molecules absorption cross section in the laboratory lidar studies and lidar equation simulation in this lidar variant corresponds with earlier data.

Keywords

  • iodine molecules
  • concentration
  • lidar
  • differential absorption cross section

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