Reference Signal Compression in Intrusive Methods for Assessing the Quality of Speech Transmission Using the Unitary Numbering System

2021 ◽  
Author(s):  
A. N. Terekhov ◽  
A. S. Korchagina
Keyword(s):  
Reference Signal ◽  
Signal Compression ◽  
Numbering System ◽  
Speech Transmission

scholarly journals Environmental Acoustic Comfort in the Built Environment

2021 ◽  
Vol 9 (71) ◽  
Author(s):  
Margret Sibylle Engel ◽  
Júlio Otávio Herrmann ◽  
Paulo Henrique Trombetta Zannin
Keyword(s):  
Teaching And Learning ◽  
Physical Structure ◽  
Sharp Drop ◽  
Speech Transmission ◽  
Acoustic Quality ◽  
Teachers And Students ◽  
Acoustic Comfort ◽  
The 1960S ◽  
Acoustic Conditions

  The acoustic quality of classrooms has a strong influence on the teaching and learning process. This interference assessed using the impulsive technique to measure the rate of speech transmission (STI), reverberation time (RT) and sound definition (D50). These are the most relevant acoustic descriptors in the assessment of classrooms, where verbal exposure is the means of communication between teachers and students. The evaluation took place in two buildings of the Federal University of Paraná (UFPR), built in the 1960s and another in 2016. The measured values ​​of STI, provided in the classrooms' actual acoustic conditions, were used as an adjustment parameter for simulations made with the software ODEON. After carrying out the measurements and simulations, the dimensioning of improvements was possible. The acoustic simulations presented suggestions to qualify the quality of the classrooms' acoustic comfort, ensuring that teaching and learning to do not suffer losses due to the physical structure of the classrooms. The measured values ​​of STI, RT and D50 show that, in the old building, except for a single classroom that preserves the original ceiling that had a high sound absorption coefficient, it has reasonable values, below the ideal for classrooms, according to the IEC 60268-16 (2011) standard. The investigation showed that the rooms with a roof replaced by a PVC covering had a sharp drop in acoustic quality. The newest building has classrooms with proper acoustic comfort conditions.

scholarly journals A prediction scheme of mobility of cognitive femtocells LTE-A / LTE-UE under different speed scenarios

2018 ◽  
Vol 7 (2.32) ◽  
pp. 64
Author(s):  
Venkata Vara Prasad Padyala ◽  
Dr K.V.D.Kiran
Keyword(s):  
Reference Signal ◽  
Base Station ◽  
Survey Analysis ◽  
Coverage Area ◽  
Soft Handover ◽  
Prediction Scheme ◽  
The Future ◽  
Hand Off ◽  
Future Demands

Cognitive Femtocells have been standardized suitably to the technical framing of the Fourth cohort compact project to place them inside and outside the cell. Cognitive femtocells expand the coverage area and meet the future demands of higher data rates. However, as a result of the massive deployment of cognitive femtocells, users experience additional delay and unnecessary deliveries. The different hand off mechanisms are 1. Hard handover (break before make) 2. Smooth or soft handover (make-before-break). This can seriously affect the quality of service (QoS) of jam sensitive applications, such as Voice over long-term evolution (VoLTE). The 4GPP LTE-A / LTE-UE wireless networks aim to provide uninterrupted movement and rapid transfer pillar for (Real Time) RT and non-RT application services under the giant vigour. The prediction of mobility is an effective technique to identify a domestic NodeB (eNB / HeNB) evolved in the future and improve the overall service quality of the network and satisfy the end user experience. The different hand over mechanisms are, the first sense of a difficult delivery or transfer is one in which an breathe link should be penetrate ahead a unused one is created. The second new 3G technologies use CDMA where it is possible to have adjoining cells at the same frequency and this opens the odds of boast a transfer or transfer from where it is not required to repair the connection. This is called soft transfer, and is defined as a handover in which a not used tie-in is established before the used one is released. The third type of delivery is called smoother delivery or transfer. In this case, a pristine signal is added or deleted from the spry signal group. It can also happen when a signal is replaced by a burly signal from another sector under the base station. This type of transfer is available within UMTS and CDMA2000. “The cognitive femtocell will do in the delivery mechanism is that it will detect the new channel to transmit the data. With this we can avoid the delivery handover mechanism”. This study investigates the role of mobility prediction in reducing the end-to-end delay of VoLTE and the delay of handover under different user equipment (UE) speeds in mixed femtocell and macrocell environments. We propose a mobility based forecasting scheme based on the user path and measurements of the received signal reference signal and the quality reference signal (RSRP / RSRQ) with mixed RT traffic and not RT and then estimated using a network model new. The survey analysis shows that the proposed scheme will reduce the delivery delay by 35% to keep VoLTE at the end of the delay.  

Improved methods for measurement of gaseous microbubbles during extracorporeal circulation

Perfusion ◽  
2002 ◽  
Vol 17 (6) ◽  
pp. 429-434 ◽  
Author(s):  
Simon Urbanek ◽  
Hans-Jürgen Tiedtke
Keyword(s):  
Artery Bypass ◽  
Reference Signal ◽  
Arterial Line ◽  
Clinical Environment ◽  
External Disturbances ◽  
Bubble Detection ◽  
On Line ◽  
Electromagnetic Disturbances ◽  
Improved Methods

The detection and quantification of gaseous microbubbles in the arterial line of the extracorporeal circuit (ECC) are very important aims for quality assurance of perfusion. A system that allows a continuous measurement of microbubble distribution in the range of 10 and 120 mm was tested. The two-channel ultrasonic bubble counter (UBC) was based on a 2-MHz ultrasound Doppler system with propriety ultrasound probes. The bubble size was determined using the backscattered Doppler signal and was corrected by means of a reference signal based on measurement conditions. Our studies have shown that the quality of this signal can be negatively affected in the clinical environment. Different influences are involved, such as electrocoagulation or electromagnetic disturbances. Various algorithms were tested and new ones were developed in order to minimize the effect of such interferenceson the accuracy of the bubble detection. The on-line data were recorded during the entire surgical time to allow an off-line evaluation with different algorithms. This allowed us to obtain more exact results. Two clinical studies with 91 patients were performed with microbubbles measured in the arterial line during coronary artery bypass grafting (CABG) and valve replacement. The results confirmed the expected occurrence of microbubbles during various phases of surgery. The measurement itself proved to be resistant to different external disturbances.

scholarly journals Improving the eNodeB Coverage of a Bad Spot Area by Using A Relay Node

2018 ◽  
Vol 2 (02) ◽  
pp. 83
Author(s):  
Fivie Ni'mah ◽  
Hasanah Putri Putri
Keyword(s):  
Field Measurement ◽  
Reference Signal ◽  
Relay Node ◽  
Decode And Forward ◽  
Spot Area ◽  
Term Evolution ◽  
Standard Values ◽  
Long Term Evolution Network

The quality of LTE (Long Term Evolution) network in WR Supratman Street, Bandung is categorized as quite bad as shown by the average RSRP (Reference Signal Receive) and SINR (Signal to Interference Noise Ratio) values of -101.30 dBm and 2.43 dB, respectively. Both parameters are below the standard operator with the average RSRP and SINR standard values of -101.30 dBm and 2.43 dB, respectively. The previous field measurement indicated that the area belonged to a bad spot area caused by shadowing buildings. This study used the node scheme of decode and forward and physical mode of inband relay node with the aim of extending the eNodeB coverage. By applying this technique, the average RSRP value increased by 18% and the average SINR value increased by 53%. Based on the RF (Radio Frequency) parameters, the average RSRP value with samples below the -85 dBm standard improved by 81%, while the average SINR value with samples below 5 dB improved by 45%.

Human Factor Problems in Satellite Telephoning

1966 ◽  
Vol 8 (6) ◽  
pp. 475-480 ◽  
Author(s):  
Edmund T. Klemmer
Keyword(s):  
Human Factor ◽  
Transmission Time ◽  
Speed Of Light ◽  
Speech Transmission ◽  
Telephone Calls

Telephone calls routed via satellite involve long transmission paths which in turn require significant transmission times even at the speed of light. This transmission time produces a delay in speech transmission of about 0.3 seconds in each direction for a synchronous satellite. Although the delay itself is not usually noticed by the talkers, it significantly increases the disturbing effects of echo and mutilation of speech by the echo suppressors so that the overall quality of the circuit, as judged by the users, suffers.

scholarly journals A Study of the Acoustics and Speech Intelligibility Quality of Mosques in Malaysia

2014 ◽  
Vol 564 ◽  
pp. 129-134
Author(s):  
Abdul Hakim Abdullah ◽  
Zamir A. Zulkefli
Keyword(s):  
Background Noise ◽  
Speech Intelligibility ◽  
Prediction Models ◽  
Signal To Noise Ratio ◽  
Distribution Patterns ◽  
Speech Quality ◽  
Transmission Index ◽  
Speech Transmission ◽  
Rapid Transmission

This study presents the assessment of the quality of speech intelligibility of two Malaysian mosques and the results are used to develop a set of general acoustical guidelines to be used in the design of a mosque. Two mosques were selected for the research: Masjid UPM and the Masjid Jamek. The objective of the research is to enable the comparison of the acoustics and speech intelligibility between the mosques as function of the size, volume, occupancy and other parameters of the main prayer hall on the acoustic and speech intelligibility of the respective mosques. The reverberation time (RT60), speech level (SL), background noise (BN), signal-to-noise ratio (S/N ratio) were determined and are used to develop the speech transmission index (STI) and rapid transmission index (RASTI) prediction models for both mosques. It was observed from the results that the RT60, STI and RASTI values shows better performance over number of occupancy for both mosques. Furthermore, the BN and SL results were visualized using the spatial distribution patterns (SDP) of the main hall. The results of the analysis show that the overall acoustic and speech quality of Masjid Jamek is better when compared to the overall acoustic and speech quality of Masjid UPM. These results are then used to develop a set of design recommendations to ensure adequate speech intelligibility quality a mosque.

scholarly journals Active power filter with hysteresis current control loop using rectifier boost technique

2020 ◽  
Vol 11 (3) ◽  
pp. 1117
Author(s):  
Rahimi Baharom ◽  
Ihsan Mohd Yassin ◽  
Nabil Hidayat
Keyword(s):  
Reference Signal ◽  
Active Power Filter ◽  
Input Voltage ◽  
Active Power ◽  
Current Control ◽  
Current Waveform ◽  
Hysteresis Current Control ◽  
Power Filter ◽  
Switching Losses

<span lang="EN-US">This paper presents the Hysteresis Current Control (HCC) to improve the power quality of power electronic converters. The development of HCC was implemented using Active Power Filter (APF) function based on rectifier boost technique to control the range of upper and lower bands. Through this technique, the supply current waveform followed the shape of the sinusoidal reference signal, thus, the distorted input current waveform becomes sinusoidal and in the same phase with the input voltage. As a result, the THD level and switching losses can be reduced, thus improving the power factor of the power supply system. In order to verify the proposed operation, validation of the proposed HCC was done through MATLAB. Selected simulation results are presented.</span>

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