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A device with a frequency-modulated output signal has been developed to increase the sensitivity and accuracy of measuring moisture content in crude oil and petroleum products in the range of 0~20%. The main element of the device is a self-oscillator transducer based on a transistor structure with negative differential resistance. A capacitive sensor in the form of a capacitive cylindrical structure...
The paper outlines the latest technologies used by the world's leading manufacturers in the development of mobile low-observable robotic systems and promising measures to improve the quality of components and design of such objects. Methods of detecting objects using stealth technologies are considered, and it is shown that only due to a system approach it is possible to compensate for the reduction...
The paper presents results of theoretical and practical researching the radiofrequency Chua's oscillator based on a tunnel diode. A mathematical model of Chua's oscillator based on a tunnel diode has been proposed, it differs from Chua's mathematical model by the changed system's third differential equation and by an approximation function of a nonlinear element. Lyapunov exponents have been calculated...
The paper proposes using a neuro-fuzzy controller in telecommunication networks for improving the routing process. An architecture of the neuro-fuzzy controller was developed. Linguistic variables, terms and membership functions for input and output values were defined. A rules base was developed. The operation of the neuro-fuzzy controller was simulated and trained.
The application of the proposed mathematical tools, that can be used for signal processing self-generating transducers of physical quantities, are considered. Its operating mechanism is based on frequency modulation, when the frequency deviation depends on the intensity of exposure measurement parameter. It is shown that the action for leveling additive errors in the channel the signal generator is...
The paper considers a new electric diagram of the microelectronic self-excited oscillator based on the bipolar transistor structure with negative resistance. The oscillator operates in oscillatory and relaxation modes. Chaotic mode of the self-excited oscillator was provided by installing additional components into a basic circuit. Results of the deterministic chaos microelectronic oscillator simulation...
The paper proposes using a neuro-fuzzy controller in mobile networks for improving the handover process. An architecture of the neuro-fuzzy controller was developed. Linguistic variables, terms and membership functions for input and output values were defined. A rules base was developed. The operation of the neuro-fuzzy controller was simulated and trained.
The deterministic chaos mode in a basic circuit of a radiofrequency oscillator based on a bipolar transistor structure with negative resistance have been studied in this paper. Experimental research results for parameters and characteristics of the bipolar transistor structure with negative resistance have been obtained. Chaotic dynamics of the generated oscillation has been explored. Feasibility...
The paper considers an electric circuit of a microelectronic oscillator based on a BJT-MOSFET structure with negative differential resistance. A mathematical model of this oscillator has been developed. Theoretical and practical researches of oscillations dynamics have been carried out. Lyapunov exponents have been calculated. Limits of periodic and chaotic oscillations modes have been determined...
In the paper a deterministic chaos oscillator based on a bipolar and field-effect transistor structure with negative resistance is proposed and examined. A modified mathematical model of Anishchenko-Astakhov is proposed for describing the chaotic oscillation dynamics. The results of mathematical modelling and experimental research are obtained.
The additive white noise impact on dynamics of the Kiyashko-Pikovsky-Rabinovich oscillator based on a field-effect transistor structure with negative resistance has been considered. The results of the mathematical modelling the deterministic chaos oscillator in presence and in absence of white noise have been obtained. The white noise impact on dynamics and parameters of the generated chaotic oscillation...
In the paper, the wide-spread mathematical models of the deterministic chaos transistor oscillators are considered. These models describe dynamic processes to take place in transistor Colpitts oscillators. Variations of the deterministic chaos transistor oscillator's schemes are presented. Phase portraits, time and spectral diagrams of chaotic oscillation were obtained.
In this paper a classical circuit of the Kiyashko-Pikovsky-Rabinovich deterministic chaos oscillator based on a field-effect transistor structure with negative resistance got the further development. The chaotic oscillation dynamic processes in this oscillator have been researched using the improved model. Phase portraits of the oscillator in different operating modes have been obtained.
The results of the mathematical modelling for the voltage-controlled oscillator based on a transistor structure with negative resistance are presented in this article. The generated oscillations with and without noise were described with the Van der Pol's model. The research was carried out for relaxation and oscillator modes of the generator.
In this paper three radiomeasuring frequency converters of the magnetic field are developed. Also their sensitivity characteristics are researched and compared. Besides, the advantages and disadvantages of each of the radiomeasuring frequency converters of the magnetic field are indicated.
The article considers a possibility of constructing microwave oscillators on a transistor structure with negative conductivity based on two HEMT. Obtained non-linear equations can be used to model microwave oscillator parameters and characteristics with an error not more than 10%.
WiMAX is a broadband wireless last mile technology providing high speeds for long distances and offering great flexibility. Scheduling in WiMAX became one of the most important tasks, because it is responsible for distributing available resources among users. A high level of quality of service and scheduling support is one of the most interesting features of the WiMAX standard. In modern telecommunication...
When combining fuzzy logic and neural networks it is possible to get a hybrid system that can process uncertain values and can be trained. Fuzzy logic elements can be regarded as fuzzy-neural networks. In order to present a set of fuzzy values the ternary encoding is used.
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