Issues

Journal & Issues

Volume 22 (2022): Issue 5 (October 2022)

Volume 22 (2022): Issue 4 (August 2022)

Volume 22 (2022): Issue 3 (June 2022)

Volume 22 (2022): Issue 2 (April 2022)

Volume 22 (2022): Issue 1 (February 2022)

Volume 21 (2021): Issue 6 (December 2021)

Volume 21 (2021): Issue 5 (October 2021)

Volume 21 (2021): Issue 4 (August 2021)

Volume 21 (2021): Issue 3 (June 2021)

Volume 21 (2021): Issue 2 (April 2021)

Volume 21 (2021): Issue 1 (February 2021)

Volume 20 (2020): Issue 5 (October 2020)

Volume 20 (2020): Issue 4 (August 2020)

Volume 20 (2020): Issue 3 (June 2020)

Volume 20 (2020): Issue 2 (April 2020)

Volume 20 (2020): Issue 1 (February 2020)

Volume 19 (2019): Issue 6 (December 2019)

Volume 19 (2019): Issue 5 (October 2019)

Volume 19 (2019): Issue 4 (August 2019)

Volume 19 (2019): Issue 3 (June 2019)

Volume 19 (2019): Issue 2 (April 2019)

Volume 19 (2019): Issue 1 (February 2019)

Volume 18 (2018): Issue 6 (October 2018)

Volume 18 (2018): Issue 5 (October 2018)

Volume 18 (2018): Issue 4 (August 2018)

Volume 18 (2018): Issue 3 (June 2018)

Volume 18 (2018): Issue 2 (April 2018)

Volume 18 (2018): Issue 1 (February 2018)

Volume 17 (2017): Issue 6 (December 2017)

Volume 17 (2017): Issue 5 (October 2017)

Volume 17 (2017): Issue 3 (June 2017)

Volume 17 (2017): Issue 2 (April 2017)

Volume 17 (2017): Issue 1 (February 2017)

Volume 16 (2016): Issue 6 (December 2016)

Volume 16 (2016): Issue 5 (October 2016)

Volume 16 (2016): Issue 4 (August 2016)

Volume 16 (2016): Issue 3 (June 2016)

Volume 16 (2016): Issue 2 (April 2016)

Volume 16 (2016): Issue 1 (February 2016)

Volume 15 (2015): Issue 6 (December 2015)

Volume 15 (2015): Issue 5 (October 2015)

Volume 15 (2015): Issue 4 (August 2015)

Volume 15 (2015): Issue 3 (June 2015)

Volume 15 (2015): Issue 2 (April 2015)

Volume 15 (2015): Issue 1 (February 2015)

Volume 14 (2014): Issue 6 (December 2014)

Volume 14 (2014): Issue 5 (October 2014)

Volume 14 (2014): Issue 4 (August 2014)

Volume 14 (2014): Issue 3 (June 2014)

Volume 14 (2014): Issue 2 (April 2014)

Volume 14 (2014): Issue 1 (February 2014)

Volume 13 (2013): Issue 6 (December 2013)

Volume 13 (2013): Issue 5 (October 2013)

Volume 13 (2013): Issue 4 (August 2013)

Volume 13 (2013): Issue 3 (June 2013)

Volume 13 (2013): Issue 2 (April 2013)

Volume 13 (2013): Issue 1 (February 2013)

Volume 12 (2012): Issue 6 (December 2012)

Volume 12 (2012): Issue 5 (October 2012)

Volume 12 (2012): Issue 4 (August 2012)

Volume 12 (2012): Issue 3 (June 2012)

Volume 12 (2012): Issue 2 (April 2012)

Volume 12 (2012): Issue 1 (February 2012)

Volume 11 (2011): Issue 6 (December 2011)

Volume 11 (2011): Issue 5 (October 2011)

Volume 11 (2011): Issue 4 (August 2011)

Volume 11 (2011): Issue 3 (June 2011)

Volume 11 (2011): Issue 2 (April 2011)

Volume 11 (2011): Issue 1 (February 2011)

Volume 10 (2010): Issue 6 (December 2010)

Volume 10 (2010): Issue 5 (October 2010)

Volume 10 (2010): Issue 4 (August 2010)

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

Volume 10 (2010): Issue 2 (April 2010)

Volume 10 (2010): Issue 1 (February 2010)

Volume 9 (2009): Issue 6 (December 2009)

Volume 9 (2009): Issue 5 (October 2009)

Volume 9 (2009): Issue 4 (August 2009)

Volume 9 (2009): Issue 3 (June 2009)

Volume 9 (2009): Issue 2 (April 2009)

Volume 9 (2009): Issue 1 (February 2009)

Volume 8 (2008): Issue 6 (December 2008)

Volume 8 (2008): Issue 5 (October 2008)

Volume 8 (2008): Issue 4 (August 2008)

Volume 8 (2008): Issue 3 (June 2008)

Volume 8 (2008): Issue 2 (April 2008)

Volume 8 (2008): Issue 1 (February 2008)

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

Search

Volume 11 (2011): Issue 6 (December 2011)

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

Search

7 Articles
access type Open Access

A Smart Measurement and Stimulation System to Analyze and Promote Non-Nutritive Sucking of Premature Babies

Published Online: 21 Dec 2011
Page range: 173 - 180

Abstract

A Smart Measurement and Stimulation System to Analyze and Promote Non-Nutritive Sucking of Premature Babies

This paper presents a complete system that can be used to measure and to stimulate sucking abilities of premature babies. The system integrates measurement and stimulation capabilities that can be used separately or together. The sensing unit includes mainly a pressure sensor, a conditioning circuit and a microcontroller device. The stimulation unit includes a miniature and low-cost pneumatic pump, an electro-valve, and a conditioning circuit. The microcontroller is shared by both units. The system's software includes a routine that is used to define the waveform parameters of the synthesized pressure signals, a wavelet based routine that is used to process measurement data and a software component to perform fault detection and diagnosis. The system capabilities include self-calibration and self-testing. Throughout the paper several implementation details and experimental results will be presented and discussed.

Keywords

  • Sucking pressure measurement
  • sucking stimulation
  • premature babies
access type Open Access

Application of Wavelet Based Denoising for T-Wave Alternans Analysis in High Resolution ECG Maps

Published Online: 21 Dec 2011
Page range: 181 - 184

Abstract

Application of Wavelet Based Denoising for T-Wave Alternans Analysis in High Resolution ECG Maps

T-wave alternans (TWA) allows for identification of patients at an increased risk of ventricular arrhythmia. Stress test, which increases heart rate in controlled manner, is used for TWA measurement. However, the TWA detection and analysis are often disturbed by muscular interference. The evaluation of wavelet based denoising methods was performed to find optimal algorithm for TWA analysis. ECG signals recorded in twelve patients with cardiac disease were analyzed. In seven of them significant T-wave alternans magnitude was detected. The application of wavelet based denoising method in the pre-processing stage increases the T-wave alternans magnitude as well as the number of BSPM signals where TWA was detected.

Keywords

  • T-wave alternans
  • wavelet denoising
  • stress test
  • arrhythmia
  • sudden cardiac death
access type Open Access

Ball's Motion Estimation Using a Line-Scan Camera

Published Online: 21 Dec 2011
Page range: 185 - 191

Abstract

Ball's Motion Estimation Using a Line-Scan Camera

An original method is proposed for estimating the position and velocity of a moving ball using a single line-scan camera. The method consists of two steps: firstly, the ball's initial position and velocity are determined by several key points in the image, and secondly, these parameters are further refined by a model-based optimization algorithm. The algorithm achieves accurate parameter estimation by matching the projection contour of the real ball and that of the same size sphere model. Finally, the relevance and accuracy of the method are experimentally confirmed on synthetic and real images.

Keywords

  • Position
  • velocity
  • ball motion estimation
  • line-scan camera
access type Open Access

Model for Cuboid Shape Samples and its Analysis Used for Measurements of Thermophysical Properties of Sandstone

Published Online: 21 Dec 2011
Page range: 192 - 197

Abstract

Model for Cuboid Shape Samples and its Analysis Used for Measurements of Thermophysical Properties of Sandstone

A new model for the sample of square cross section with cuboid geometry including the effect of heat loss from the surface of the sample was tested using the theory of sensitivity coefficients. Theoretical calculation of model uncertainty and derived analytical formulas are presented. Results of the uncertainty analysis set out the range of experimental conditions under which the model is valid and the uncertainty of estimated parameters is low. Propagation of error for non-stochastic dynamic measurements based on the sensitivity coefficients shows limitations related to a range of model validity. The analysis improves the accuracy of measurements. The model was used for data evaluation of thermophysical parameters measured on the sandstone from the locality Pravčická brána. Evaluation procedure was tested on experimental data measured under different experimental conditions. In conclusion, the discussion of the experiment optimization is presented.

Keywords

  • Pulse transient method
  • sensitivity coefficient analysis
  • thermophysical properties
access type Open Access

A Computer Controlled Precision High Pressure Measuring System

Published Online: 21 Dec 2011
Page range: 198 - 202

Abstract

A Computer Controlled Precision High Pressure Measuring System

A microcontroller (AT89C51) based electronics has been designed and developed for high precision calibrator based on Digiquartz pressure transducer (DQPT) for the measurement of high hydrostatic pressure up to 275 MPa. The input signal from DQPT is converted into a square wave form and multiplied through frequency multiplier circuit over 10 times to input frequency. This input frequency is multiplied by a factor of ten using phased lock loop. Octal buffer is used to store the calculated frequency, which in turn is fed to microcontroller AT89C51 interfaced with a liquid crystal display for the display of frequency as well as corresponding pressure in user friendly units. The electronics developed is interfaced with a computer using RS232 for automatic data acquisition, computation and storage. The data is acquired by programming in Visual Basic 6.0. This system is interfaced with the PC to make it a computer controlled system. The system is capable of measuring the frequency up to 4 MHz with a resolution of 0.01 Hz and the pressure up to 275 MPa with a resolution of 0.001 MPa within measurement uncertainty of 0.025%. The details on the hardware of the pressure measuring system, associated electronics, software and calibration are discussed in this paper.

Keywords

  • Digital pressure calibrator
  • computer controlled pressure measurements
  • precision high pressure measuring system
  • pressure sensor
  • pressure transducer
access type Open Access

Determination of Moisture Content in Mortar at Near Relaxation Frequency 17 GHz

Published Online: 21 Dec 2011
Page range: 203 - 206

Abstract

Determination of Moisture Content in Mortar at Near Relaxation Frequency 17 GHz

The knowledge of moisture content in cement based material is important especially for the safety in field work. In this paper, a non-destructive and contactless free space method is used for measurement of moisture content in cement based materials (mortar) at microwave frequencies. The measurement system consists of a 17 GHz dielectric resonator oscillator (DRO) as a microwave source, a Power Meter as the detector, and a pair of lens horn antennas to transmit and receive the microwave signal. An empirical formula of moisture content was obtained by using a relationship between attenuation and moisture content. This model is best for prediction of moisture content greater than 2% with percentage mean error of 3%.

Keywords

  • Mortar
  • attenuation
  • moisture content
  • nondestructive technique (NDT)
  • free space
  • transmission
access type Open Access

FPGA Based Linear Heating System for Measurement of Thermoluminescence

Published Online: 21 Dec 2011
Page range: 207 - 209

Abstract

FPGA Based Linear Heating System for Measurement of Thermoluminescence

A linear heating system has been developed using field programmable gate array (FPGA) for the measurement of thermoluminescence (TL) in alkali halides and other related compounds. Thermoluminescence plays an essential part in radiation dosimetry. This system measures the temperature and the amount of light emitted by the sample for TL studies. This work proposed an architectural framework, verilog HDL code for protocols for reading temperature from Thermocouple through ADC, processing of data (amount of light energy) in FPGA, sending control signal to the heater and displaying the temperature in LCD. This work shows performance improvement 3 times in comparison with conventional embedded system. The power consumption is also comparatively lower.

Keywords

  • Thermocouple
  • field programmable gate array
  • linear system
  • thermoluminescence
  • temperature measurement
7 Articles
access type Open Access

A Smart Measurement and Stimulation System to Analyze and Promote Non-Nutritive Sucking of Premature Babies

Published Online: 21 Dec 2011
Page range: 173 - 180

Abstract

A Smart Measurement and Stimulation System to Analyze and Promote Non-Nutritive Sucking of Premature Babies

This paper presents a complete system that can be used to measure and to stimulate sucking abilities of premature babies. The system integrates measurement and stimulation capabilities that can be used separately or together. The sensing unit includes mainly a pressure sensor, a conditioning circuit and a microcontroller device. The stimulation unit includes a miniature and low-cost pneumatic pump, an electro-valve, and a conditioning circuit. The microcontroller is shared by both units. The system's software includes a routine that is used to define the waveform parameters of the synthesized pressure signals, a wavelet based routine that is used to process measurement data and a software component to perform fault detection and diagnosis. The system capabilities include self-calibration and self-testing. Throughout the paper several implementation details and experimental results will be presented and discussed.

Keywords

  • Sucking pressure measurement
  • sucking stimulation
  • premature babies
access type Open Access

Application of Wavelet Based Denoising for T-Wave Alternans Analysis in High Resolution ECG Maps

Published Online: 21 Dec 2011
Page range: 181 - 184

Abstract

Application of Wavelet Based Denoising for T-Wave Alternans Analysis in High Resolution ECG Maps

T-wave alternans (TWA) allows for identification of patients at an increased risk of ventricular arrhythmia. Stress test, which increases heart rate in controlled manner, is used for TWA measurement. However, the TWA detection and analysis are often disturbed by muscular interference. The evaluation of wavelet based denoising methods was performed to find optimal algorithm for TWA analysis. ECG signals recorded in twelve patients with cardiac disease were analyzed. In seven of them significant T-wave alternans magnitude was detected. The application of wavelet based denoising method in the pre-processing stage increases the T-wave alternans magnitude as well as the number of BSPM signals where TWA was detected.

Keywords

  • T-wave alternans
  • wavelet denoising
  • stress test
  • arrhythmia
  • sudden cardiac death
access type Open Access

Ball's Motion Estimation Using a Line-Scan Camera

Published Online: 21 Dec 2011
Page range: 185 - 191

Abstract

Ball's Motion Estimation Using a Line-Scan Camera

An original method is proposed for estimating the position and velocity of a moving ball using a single line-scan camera. The method consists of two steps: firstly, the ball's initial position and velocity are determined by several key points in the image, and secondly, these parameters are further refined by a model-based optimization algorithm. The algorithm achieves accurate parameter estimation by matching the projection contour of the real ball and that of the same size sphere model. Finally, the relevance and accuracy of the method are experimentally confirmed on synthetic and real images.

Keywords

  • Position
  • velocity
  • ball motion estimation
  • line-scan camera
access type Open Access

Model for Cuboid Shape Samples and its Analysis Used for Measurements of Thermophysical Properties of Sandstone

Published Online: 21 Dec 2011
Page range: 192 - 197

Abstract

Model for Cuboid Shape Samples and its Analysis Used for Measurements of Thermophysical Properties of Sandstone

A new model for the sample of square cross section with cuboid geometry including the effect of heat loss from the surface of the sample was tested using the theory of sensitivity coefficients. Theoretical calculation of model uncertainty and derived analytical formulas are presented. Results of the uncertainty analysis set out the range of experimental conditions under which the model is valid and the uncertainty of estimated parameters is low. Propagation of error for non-stochastic dynamic measurements based on the sensitivity coefficients shows limitations related to a range of model validity. The analysis improves the accuracy of measurements. The model was used for data evaluation of thermophysical parameters measured on the sandstone from the locality Pravčická brána. Evaluation procedure was tested on experimental data measured under different experimental conditions. In conclusion, the discussion of the experiment optimization is presented.

Keywords

  • Pulse transient method
  • sensitivity coefficient analysis
  • thermophysical properties
access type Open Access

A Computer Controlled Precision High Pressure Measuring System

Published Online: 21 Dec 2011
Page range: 198 - 202

Abstract

A Computer Controlled Precision High Pressure Measuring System

A microcontroller (AT89C51) based electronics has been designed and developed for high precision calibrator based on Digiquartz pressure transducer (DQPT) for the measurement of high hydrostatic pressure up to 275 MPa. The input signal from DQPT is converted into a square wave form and multiplied through frequency multiplier circuit over 10 times to input frequency. This input frequency is multiplied by a factor of ten using phased lock loop. Octal buffer is used to store the calculated frequency, which in turn is fed to microcontroller AT89C51 interfaced with a liquid crystal display for the display of frequency as well as corresponding pressure in user friendly units. The electronics developed is interfaced with a computer using RS232 for automatic data acquisition, computation and storage. The data is acquired by programming in Visual Basic 6.0. This system is interfaced with the PC to make it a computer controlled system. The system is capable of measuring the frequency up to 4 MHz with a resolution of 0.01 Hz and the pressure up to 275 MPa with a resolution of 0.001 MPa within measurement uncertainty of 0.025%. The details on the hardware of the pressure measuring system, associated electronics, software and calibration are discussed in this paper.

Keywords

  • Digital pressure calibrator
  • computer controlled pressure measurements
  • precision high pressure measuring system
  • pressure sensor
  • pressure transducer
access type Open Access

Determination of Moisture Content in Mortar at Near Relaxation Frequency 17 GHz

Published Online: 21 Dec 2011
Page range: 203 - 206

Abstract

Determination of Moisture Content in Mortar at Near Relaxation Frequency 17 GHz

The knowledge of moisture content in cement based material is important especially for the safety in field work. In this paper, a non-destructive and contactless free space method is used for measurement of moisture content in cement based materials (mortar) at microwave frequencies. The measurement system consists of a 17 GHz dielectric resonator oscillator (DRO) as a microwave source, a Power Meter as the detector, and a pair of lens horn antennas to transmit and receive the microwave signal. An empirical formula of moisture content was obtained by using a relationship between attenuation and moisture content. This model is best for prediction of moisture content greater than 2% with percentage mean error of 3%.

Keywords

  • Mortar
  • attenuation
  • moisture content
  • nondestructive technique (NDT)
  • free space
  • transmission
access type Open Access

FPGA Based Linear Heating System for Measurement of Thermoluminescence

Published Online: 21 Dec 2011
Page range: 207 - 209

Abstract

FPGA Based Linear Heating System for Measurement of Thermoluminescence

A linear heating system has been developed using field programmable gate array (FPGA) for the measurement of thermoluminescence (TL) in alkali halides and other related compounds. Thermoluminescence plays an essential part in radiation dosimetry. This system measures the temperature and the amount of light emitted by the sample for TL studies. This work proposed an architectural framework, verilog HDL code for protocols for reading temperature from Thermocouple through ADC, processing of data (amount of light energy) in FPGA, sending control signal to the heater and displaying the temperature in LCD. This work shows performance improvement 3 times in comparison with conventional embedded system. The power consumption is also comparatively lower.

Keywords

  • Thermocouple
  • field programmable gate array
  • linear system
  • thermoluminescence
  • temperature measurement

Plan your remote conference with Sciendo