Математика, механика, информатика. Рубрика в журнале - Сибирский аэрокосмический журнал
Robust and reliable techniques for speech-based emotion recognition
Статья научная
One of the crucial challenges related to the spacecraft control is the monitoring of the mental state of crew members as well as operators of the flight control centre. In most cases, visual information is not sufficient, because spacemen are trained to cope with feelings and not to express emotions explicitly. In order to identify the genuine mental state of a crew member, it is reasonable to engage the acoustic characteristics obtained from speech signals presenting voice commands during the spacecraft control and interpersonal communication. Human emotion recognition implies flexible algorithmic techniques satisfying the requirements of reliability and fast operation in real time. In this paper we consider the heuristic feature selection procedure based on the self-adaptive multi-objective genetic algorithm that allows the number of acoustic characteristics involved in the recognition process to be reduced. The effectiveness of this approach and its robustness property are revealed in experiments with various classification models. The usage of this procedure leads to a reduction of the feature space dimension by a factor of two (from 384 to approximately 180 attributes), which means decreasing the time resources spent by the recognition algorithm. Moreover, it is proposed to implement some algorithmic schemes based on collective decision making by the set of classifiers (Multilayer Perceptron, Support Vector Machine, Linear Logistic Regression) that permits the improvement of the recognition quality (by up to 10% relative improvement). The developed algorithmic schemes provide a guaranteed level of effectiveness and might be used as a reliable alternative to the random choice of a classification model. Due to the robustness property the heuristic feature selection procedure is successfully applied on the data pre-processing stage, and then the approaches realizing the collective decision making schemes are used.
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SVM-based classifier ensembles design with co-operative biology inspired algorithm
Статья научная
The meta-heuristic called Co-Operation of Biology Related Algorithms (COBRA) is used for the automated design of a support vector machine (SVM) based classifiers ensemble. Two non-standard schemes, based on the use of the locally most effective ensemble member’s output, are used to infer the ensemble decision. The usefulness of the approach is demonstrated on four benchmark classification problems solved: two bank scoring problems (Australian and German) and two medical diagnostic problems (Breast Cancer Wisconsin and Pima Indians Diabetes). Numerical experiments showed that classifier ensembles designed by COBRA exhibit high performance and reliability for separating instances from different categories. Ensembles of SVM-based classifiers implemented in this way outperform many alternative methods on the mentioned benchmark classification problems.
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Scene image construction by way of sequenced images superposition
Статья научная
A concept of scene image construction by way of video sequence frames or photo shot series superposition is presented in the paper. Scene construction is performed on the basis of displacement map which reflects vectors of blocks shifts.
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Self-configuring multi-strategy genetic algorithm for non-stationary environments
Статья научная
Many real-world problems of design and control in a field of the aerospace lead to optimization problems. Such optimization problems are complicated and become a great challenge to many optimization techniques. Moreover, many real-world optimization problems are dynamic and changing over time. Changes occur in the parameters, objectives and/or problem constraints. In this case, search algorithms should have the capability to track moving optima and adapt to a new environment. In past years many approaches for non-stationary optimization were proposed. The best results are achieved using a stochastic population-based search such as evolutionary and genetic algorithms. Unfortunately, real-world non-stationary optimization problems include various types of changes and are poorly predictable, thus there is a problem of choosing a proper optimization technique and tuning its parameters. This study presents a novel approach for designing a multi-strategy genetic algorithm based on a hybrid of the island model, cooperative and competitive coevolution schemes. The approach controls interactions of different genetic algorithms and leads to the self-configuring solving of problems with a priori unknown structure. A short survey on non-stationary optimization problem and methods is presented. The results of numerical experiments for benchmark problems from the CEC competition are discussed. The proposed approach has demonstrated efficiency comparable with other well-studied techniques for non-stationary optimization. And it has significant advantage - it does not require the participation of the human-expert, because it operates in an automated, self-configuring way.
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Signals transmission by invariant method with further non-linear processing under weak correlation
Статья научная
The invariant system of information processing based on square-law characterized non-linear processing has been synthesized. In calculating of the parameters of such system it is assumed that the readings of the sub-carrier are interfered with additive noise and weakly correlated with each other. The quantitative estimation of the operation of such system is compared with the quantitative indications of the classical system with amplitude modulation and with the characteristics of the invariant system on the basis of extended synchronous detection.
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Статья научная
The exchange mechanism influence on the electrons ordering on eg orbitals in a chain and in a two-dimensional Heisenberg model with exchange anisotropy for a S = 1/2 spin is determined by a quantum Monte Carlo method. The existence regions of a long-range quasi-one- and two-dimensional antiferromagnetic order with the special exchange topology are determined. The plateau existence region in the field dependence of magnetization, as well as the wave vector of the magnetic structure modulation with Q = p/2 in the (magnetic field - exchange alternating) plane, is determined.
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Статья научная
An information processing invariant system based on a linear detector in conditions of inaccurate determination of thresholds is considered. Quantitative estimation of noise immunity of such a system with its further comparison with noise immunity of an ordinary binary system with non-coherent reception is carried out.
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Stochastic network equilibrium search with applications in the gas transportation model of Russia
Статья научная
We suggest an equilibrium search methodology under uncertainty conditions using the example of gas transportation model of Russia. This model includes gas producers and consumers that are joined by the network. Two-stage approach to finding the network equilibrium is described in details. For the first stage we investigate the method of demand and supply functions forming for gas consumers and producers that let us to find the equilibrium price as well as production and consumption volumes of gas. On the second stage we formulate a problem of finding the optimal plan of gas transportation with the network constraints. Then we add to our model the case of demand uncertainty and state a problem of finding the stochastic equilibrium in the gas transportation model. Gas production volume and price which provide demand satisfaction with specified probability is determined in our model. Described method of finding the stochastic equilibrium is applied to the gas transportation model of Russia. Results of numerical calculations are also given in this paper.
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Study of hydrodynamics features in the apparatuses with movable nozzle
Статья научная
Apparatuses for the heat and mass transfer processes must be designed so that they have a maximum contact sur- face. Classification of heat-mass exchange apparatuses provides geometric features of the apparatus and the hydrodynamic condition they create. However, the main trend which remains dominant in the design of such apparatus is to create a thin film of liquid on the surface of the nozzle. The work was aimed at choosing the solution in which the MN of the heat-mass exchange apparatuses can be used to implement the contact handling process of gases and liquids with density values clarification of the nozzle elements (ρnе) and the column dynamic height (Нст) and obtain the specified calculated dependences which describe the hydrody- namics and mass transfer in the apparatuses with a movable nozzle, that is to create bases for engineering calculations. Research methods were theoretical study and experimental studies on heat and mass transfer devices with movable nozzle. The best ranger for mass transfer processes implementation is that of ρneІІ (ρ = 200-700 kg/m3), which is distin- guished by a wide working area according to wg, acceptable values of fluid withdrawal and a relatively small dynamic layer height. Within the described mode, we can distinguish the area wg @ 4.7-6.0 m/s, where there is no dependence of Hp on wg. Specified calculated dependence obtained which describes the hydrodynamics and heat and mass transfer in the apparatuses with a movable nozzle.
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System for processing highly specialized information in distributed networks
Статья научная
A new structure of a system for arranging and control of highly specialized information in corporate systems is proposed. The principle difference of the given structure is that it is capable to process multilinguistic information within one user's inquiry.
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Technology of producing fibrous structure wire from chips of aluminum–magnesium–silicon alloys
Статья научная
A technological scheme for processing the scrap of aluminum–magnesium–silicon alloy in the form of friable chips into rods and wire is introduced. This scheme is based on the powder metallurgy methods. The characteristic structure and the level of mechanical properties of the produced wire are denoted.
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Testing the algorithm of the “Caterpillar”-SSA method for time series recovery
Статья научная
The basic algorithm of the “Caterpillar”-SSA method is considered and tested.
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Статья научная
The influence of selective circuits of digital-analogue converters at primary pulsed-code conversion on distortion of input signal of coders with audio data compression is considered.
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The application of image enhancement method for face recognition systems
Статья научная
Three-step face recognition algorithm which includes non-linear enhancement (dynamic range compression) and faces localization on the basis of skin color segmentation with subsequent extraction of anthropometric face points is proposed. The process of face recognition on the basis of principal component analysis is also considered.
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Статья научная
The paper considers the issue of restoring the level of the telemetry signal carrier frequency at digital processing in the automatic carrier control tract and the calculation of the threshold for taking the decision about the validity of received information symbol from the spacecraft and carrier rocket. We have described the applied method and algorithm for calculating the level of the carrier frequency and the level of threshold for making a solution based on histogram processing of the signal from the output of the frequency detector.
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The asymptotic probabilistic genetic algorithm
Статья научная
This paper proposes the modification of probabilistic genetic algorithm, which uses genetic operators, not affecting the particular solutions, but the probabilities distribution of solution vector's components. This paper also compares the reliability and efficiency of the base algorithm and proposed modification using the set of test optimization problems and bank loan portfolio problem.
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The automation process procedures of the subsystems block verification for space vehicles management
Статья научная
Described are the automation procedures for the software of logic verification in subsystem of the management perspective space vehicle block functioning. The achieved results by the implementation of these procedures are presented.
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The fast algorithm of intermediate perspectives reconstruction on a stereopair
Статья научная
Here we have considered the effective A. A. Lukianitsa algorithm of stereo-reconstruction. We have offered a modification of the particular algorithm, which allows increase in the speed of the algorithm functioning. We have also presented the results of the conducted experiments.
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Статья научная
The correlation between the size of a positive mobile charge and electronic conductivity of oxide on polycrystalline silicon is established with the help of experimental method of thermally stimulated polarization and depolarization of MIS-structures. The boundary conditions of a problem for the working model of behavior of a mobile charge in isolating layers generated on a rough semiconductor film are formulated.
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The methods of modelling and the efficiency factors in investment projects
Статья научная
In this research we have classified the methods of investment project modeling, made a comparative analysis of the given methods, and studied their advantages, disadvantages, and the directions of application. The efficiency factors of the investment project are displayed, based on the developed of enterprise net profit algorithm calculation.
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