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The paper presents a modelling tool applied to bio-products in order to quantify the pollutants formation evolution within physical-chemical conversion processes based on bond graph methodology. The study results revealed the importance of an accurate modelling tool that integrates advanced chemical dynamics information for the prediction of reaction products formation, especially for the fast reacting...
Electronical power and control systems can decisively influence the performance of the piezoelectric engines and actuators. This paper presents the modeling of some ultrasonic motor and the role of some equipments that amplifies signals of variable frequency with the lower limit of 20 kHz and various wave forms, in order to obtain new performance in using the types of engines achieved in the Research...
The paper presents the importance of the steam generator in the operation of power plants, stressing the importance of their management and automation to increase energy efficiency of each link in the chain. It presents mathematical model in absolute units from the air preheater. Modelling is based on physical model of the air preheater steam generator, simplifying assumptions adopted and the conservation...
This paper presents a study on parallel coupling operation of multiple pumps. It is known that it is always better to couple pumps with identical characteristics, although practical situations are never ideal, therefore we have taken into consideration the situation where we have available just pumps with different characteristics. A mathematical model has been realized and a Matlab simulation scheme...
This paper analyzes a spectrum reuse scheme based on region division for secondary users in cognitive radio networks with outage constraint of the primary user. The secondary users can reuse the spectrum by sharing the primary user's uplink (UL) frequency resources in the system. With the help of the stochastic geometry, the secondary user reusing the frequency spectrum can be modeled as the probability...
Fire accidents are one of the major problems facing ship, ship fire specific gravity of shipwreck increases year by year. Toxicity and high-temperature of smoke produced in fire is responsible for most of the fatalities. In order to improve the technical level of emergency during ship fire, grope for methods to describe the spreading rule of ship fire and smoke, in this research a novelty simulation...
Wireless Sensor Network as an important technology of Internet of things' development, is more and more widely used in various research fields. This paper mainly researches the part of localization application based on wireless sensor network, focuses on DV-Hop localization algorithm, and gives its algorithm simulation and analysis of the simulation results. Also this paper improves the algorithm...
The paper firstly establishes a port-controlled Hamiltonian dissipation (PCHD) based model of a direct-drive permanent magnet synchronous generator (D-PMSG). A new double loop control of the D-PMSG is proposed with the outer speed loop controlled by a non-singular higher-order terminal sliding mode (NHTSM) controller to undertake maximum wind power point tracking (MPPT). In the inner current control...
In this paper a novel adaptive Maximum Torque per Ampere (MTPA) control scheme of an interior permanent magnet synchronous machine (IPMSM) is introduced. To avoid an on- or off-line numerical calculation of the reference current for the MTPA curve, a reference model of the torque which is equivalent to the IPMSM with zero d-axis current is utilized to enforce the torque of the IPMSM towards its reference...
Cognitive diagnosis models (CDMs) are of growing interest in test development and in the measurement of human performance. The DINA (deterministic input, noisy, and gate) model has been widely used in cognitive diagnosis tests and in the process of test development. Central to many such models, the well-known Q-matrix [1], which specifies the item-attribute relationships and two noise parameters in...
Multi-terminal High Voltage dc Transmission (MTDC) is used to reduce the power losses over two distant regions. It is difficult for typical three level inverters to reach the desired dc bus voltage levels, e.g. > 500 kV, due to the large voltage stress on each switch and switching transients. For this reason, Modular Multilevel Converters (MMC) have gained popularity in High Voltage dc Transmission...
Time-domain intentional electromagnetic interference (IEMI) signals can be very fast, making it difficult and costly for any detection, location or identification system to digitize them with full time and amplitude resolutions. This paper presents a novel technique for the identification of the type of waveform associated with an IEMI attack and for the estimation of the waveform parameters based...
In this paper, Time Difference Of Arrival (TDOA) association problem in 2 dimensional localization is discussed. In 2 dimensional localization, at least three sensors are necessary to locate an emitter. When 2 or more emitters exist, there are multiple number of TDOAs obtained at each cross correlation process. In this case, it is necessary to associate TDOA to the right emitter. The problem here...
This paper deals with the analytical description of an interior permanent magnet synchronous motor running in six-step conduction mode. It assumes a non-sinusoidal back emf, but inductances vary sinusoidally with the rotor position. The proposed model renounces Park's transformation and delivers a set of equations which allow the numerical simulation of phase currents and torque in the abc reference...
The simple adaptive-robust control algorithm for time-invariant uncertain linear plants is proposed. Only scalar input and output of the plant are available for measurement. Algorithm provides tracking of a plant output to a reference signal with required accuracy. Simulations results illustrating an efficiency of proposed scheme are presented.
This paper presents a method to model the drain current of LDMOS working in the 3rd quadrant (Vds<0), which is important for power management IC design. The DIBL effect in 3rd quadrant is shown to be much more significant than that in 1st quadrant (Vds>0), and is not captured by the existing LDMOS models. Also, the threshold voltage model is not accurate in 3rd quadrant, where the drain-body...
The routing policy Size Interval Task Assignment (SITA) isolates small arrivals from large arrivals, while choosing intervals to balance the workload of each server. It works well for highly variable arrivals, but the isolation can cause server idle-ness. To improve this, we suggest a scheme to add pooling to these SITA-like systems, which can result in better performance. We propose a routing policy,...
The most industrial applications use the variation of the torque, speed and/or position in process, for which extremely severe specifications are needed. In the field of the drive of the electric machines, the elimination of the mechanical speed sensor can present an economic interest and improve safety of operation. One thus tries to make fulfill the speed measurement by implementing in a Digital...
This paper presents a modified s-to-z transformation of VVGS and VVG- Al-SKG rule, that is expanded for fractional powers based on the principle of continued fraction expansion (CFE). The magnitude response is observed to be improved at low frequencies as compared to the VVGS and VVG-AL-SKG operator. The paper also introduces a generalized design of a half differentiator based on the Al-Alaoui principle,...
In this paper a dynamic model is proposed for a wheeled mobile robot (WMR) that incorporates a novel slip characterization and is used to study navigation under hard control constraints. Many available dynamic models of WMR assume that either the wheels roll without slipping or has longitudinal slip only. As a result they do not necessarily capture the true dynamics of WMRs. The model proposed in...
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