- TITLE:
RESEARCH OF HODOGRAPHS OF REPRESENTATIVE VECTORS OF A SINGLE-THREE PHASE CYCLOCONVERTER ELECTRICAL DRIVE
- AUTHOR(S):
C. Petkov
- ABSTRACT:
The paper deals with the results for representative vectors researches of induction motor stator and rotor currents. The motor is driven by single-three phase cycloconverter. The researches are based on simulation model created by means of block modeling package Simulink of MATLAB computer mathematical system. The operating principle and model simulated are discussed. The hodographs shapes of stator and rotor representative vectors for different values of frequency are shown. Important conclusions are done also.
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RESEARCH OF HODOGRAPHS OF REPRESENTATIVE VECTORS OF A SINGLE-THREE PHASE CYCLOCONVERTER ELECTRICAL DRIVE
- TITLE:
RESEARCH THE INFLUENCE OF THE INTENSITY OF RECEIVING CALLS »I AND THE SIZE OF THE QUEUE q ON AVERAGE A RESIDENCE TIME FOR IN THE SYSTEM W AND THE PROBABILITY OF LOSSES B ON TELETRAFFIC MODEL OF VOICE SOURCES
- AUTHOR(S):
I. S. Balabanova, G. I. Georgiev
- ABSTRACT:
The regression analysis is a method allows to study the relationship between a dependent variable y, and multiple independent variables x1, x2 .... xn, which in statistical terms affect climate y. Independent variables are called factors, dependent parameters (responses) research facility. The essence of the analysis consists in the search for natural functional context of the type y = f (x1, x2, ... .x n), expressing the action
of the effects of each of the independent dependent on (target) variable. In this work are presented results of research of the influence of the intensity of receiving calls λI and size of the queue q on average downtime W and the probability of losses B on teletraffic model of voice sources with the use of regression analysis. The research is conducted with software Statistica.
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RESEARCH THE INFLUENCE OF THE INTENSITY OF RECEIVING CALLS »I AND THE SIZE OF THE QUEUE q ON AVERAGE A RESIDENCE TIME FOR IN THE SYSTEM W AND THE PROBABILITY OF LOSSES B ON TELETRAFFIC MODEL OF VOICE SOURCES
- TITLE:
RESEARCH THE INFLUENCE OF THE INTENSITY OF RECEIVING CALLS »I AND THE SIZE OF THE QUEUE q ON AVERAGE A RESIDENCE TIME FOR IN THE SYSTEM W AND THE PROBABILITY OF LOSSES B ON TELETRAFFIC MODEL OF VOICE SOURCES
- AUTHOR(S):
I. S. Balabanova, G. I. Georgiev
- ABSTRACT:
The regression analysis is a method allows to study the relationship between a dependent variable y, and multiple independent variables x1, x2 .... xn, which in statistical terms affect climate y. Independent variables are called factors, dependent parameters (responses) research facility. The essence of the analysis consists in the search for natural functional context of the type y = f (x1, x2, ... .x n), expressing the action
of the effects of each of the independent dependent on (target) variable. In this work are presented results of research of the influence of the intensity of receiving calls λI and size of the queue q on average downtime W and the probability of losses B on teletraffic model of voice sources with the use of regression analysis. The research is conducted with software Statistica.
- DOWNLOAD:
RESEARCH THE INFLUENCE OF THE INTENSITY OF RECEIVING CALLS »I AND THE SIZE OF THE QUEUE q ON AVERAGE A RESIDENCE TIME FOR IN THE SYSTEM W AND THE PROBABILITY OF LOSSES B ON TELETRAFFIC MODEL OF VOICE SOURCES
- TITLE:
BOTTLENECK FOR EXTERNAL INDEX DATA STRUCTURES
- AUTHOR(S):
I. Tronkov
- ABSTRACT:
One of the most important characteristics of the data base management system (DBMS) is the index maintenance. Thanks to them it is possible to acquire certain knowledge from the information stored in the data base, without the necessity to go round all the data. Therefore the complete performance of the DMBS depends, on a great extent, on the indexing technology, which is used. As a result of the physical limitation of the external storage devices, one of the most important tests for each index data structure is the indexing of the incoming records with random keys. This article shows such comparison test of the speed among the different classes indexing technologies.
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BOTTLENECK FOR EXTERNAL INDEX DATA STRUCTURES
- TITLE:
SIMULATION RESEARCH OF DVB-T WITH MODULATION CONSTELLATIONS QPSK, 16QAM AND 64QAM
- AUTHOR(S):
T. Manev, N. Tashkov
- ABSTRACT:
In this paper comparative analysis is made for the required signal to noise ratios for the different modulation constellations QPSK, 16QAM and 64QAM for DVB-T, where BER=1*10 -7 is achieved. This guarantees quality transmission of the modulated data. Using the standard model for digital modulation 64QAM for DVB-T in MATLAB/Simulink, new models are created for QPSK и 16QAM. This allows for comparative analysis and evaluation of transfer speeds in different signal to noise ratios.
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SIMULATION RESEARCH OF DVB-T WITH MODULATION CONSTELLATIONS QPSK, 16QAM AND 64QAM
