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This paper proposes a new approach to implement Frequency Selective Surfaces (FSSs) with sharp transition edges and almost flat bandpass responses. The design is suitable for submillimetre wave and terahertz applications. The proposed structure exhibits a low insertion loss in the desired band. The structure is realized by combining bandstop and bandpass FSS structures on the same plane. By cascading...
This paper presents a new type of cross coupled low loss and high selectivity bandpass filter operating at millimeter wave band. The filter is designed based on groove gap waveguide technology. A Ka-band 4th-order bandpass filter is proposed, designed and fabricated. Cross coupling between a one pair of non-adjacent resonators has been introduced to produce two transmission zeros at the frequencies...
The prediction of EMI sources in electrical and digital devices is not a simple task. In practice it is difficult to predict all the possible sources of EMI, from even relatively simple devices. This paper reviews and summarizes the possible EMI sources and the numerical electromagnetic modeling techniques that can be used to analyze these sources of electromagnetic interference. Although there are...
The finite-difference time-domain technique (FDTD) is used to model electromagnetic systems with lumped elements. The FDTD equations are modified to account for the presence of lumped elements such as R, L, and C and current or voltage sources inside the grid. FDTD equations that include nonlinear elements, i.e., diodes and transistors arc derived.
In this paper the finite difference time domain (FDTD) method is employed to model and predict the radiation patterns of a bent-slot half-wavelength dipole on a rectangular conducting box. Radiation patterns obtained using the FDTD are compared well with published results.
A novel approach to design a miniaturized frequency selective surface (FSS) is proposed. The miniaturization is achieved by enhancing the inductance of the proposed stepped-impedance array element. This enhancement is done by using a micro-wire and controlling the path of the current which passes through the metallic surface of the element. As a result, the dimensions of the miniaturized element are...
This paper proposes the design of a dual polarization frequency selective surface (FSS). The FSS displays a high transmission, wide operational band, excellent band edge transition and dual polarization. The bandwidth of the bandpass FSS is up to 2.1 GHz at 5.26 GHz resonant frequency. The FSS has a similar transmission coefficient for different polarisations, although the structure is not rotationally...
Electromagnetic Transients Program is used to model the lightning current distribution within the CN Tower and the attached channel. The tower is modeled by either three or five transmission line sections connected in series. On the assumption of the absence of an upward-connecting leader, the lightning channel is represented by a transmission line with a continuously expanding length. The presented...
This work advocates the use of neuro-fuzzy based approach for the task of modeling nonlinear dynamic objects using Adaptive (Hybrid) learning mechanism in unknown environment. It aims to give to new researchers description on ANFIS capability to model nonlinear plants; i.e., combining (NN) and (FL) in what is referred in literature as "neuro-fuzzy". This combination seems natural because...
Traction control system (TCS) helps regulating wheel slip when vehicle starts from rest or accelerates excessively. It limits the slip either by applying braking torque or suppressing the engine torque or by using both techniques. The brakes has faster response than the engine; however, overusing brakes decrease its lifetime and increase the fuel consumed. In this paper, a TCS is proposed that utilizes...
For any space mission operations, safety and reliability are the most important issues. Sophisticated and accurate fault detection and diagnosis of monitoring processes can minimize downtime, increase safety of space and ground operations, and reduce costs. To tackle this problem, system operations telemetry data was studied and analyzed to automatically characterize normal system behavior and anomaly...
This article presents a content-based image classification system to monitor the ripeness process of bell pepper (sweet pepper) via investigating and classifying the different maturity/ripeness stages. The proposed approach consists of three phases; namely pre-processing, feature extraction, and classification phases. Since the color of bell pepper surface is the most important characteristic to observe...
Although initial observations of lightning strikes to the CN Tower commenced in 1978, the comprehensive phase of CN Tower lightning investigations emerged in 1989. By the summer of 1990, measurement stations started to operate to simultaneously record all important parameters of CN Tower lightning flashes, including flash-optical characteristics, return-stroke currents and the associated lightning...
This paper presents a simple control strategy for the operation of a variable speed stand-alone wind turbine with a permanent magnet synchronous generator (PMSG). The PMSG is connected to a three phase resistive load through a switch mode rectifier and a voltage source inverter. Control of the generator side switch mode rectifier is used to achieve maximum power extraction from wind power. Control...
This paper presents a load power management control strategy for the operation of a stand-alone variable speed wind turbine with a permanent magnet synchronous generator (PMSG) based on the state of charge (SOC) of the battery. The PMSG is connected to a three phase load through a switch mode rectifier and a voltage source inverter. Battery storage system is connected to the DC-link voltage through...
This paper presents a simple control strategy for a variable speed wind energy conversion system with a permanent magnet synchronous generator (PMSG). PMSG is connected to the grid through a switch mode rectifier and a voltage source inverter. The grid should be supplied by certain levels of powers for certain times from wind energy system according to a certain schedule. Batteries bank is connected...
This paper presents a method based on particle swarm optimization and the lightning return-stroke current derivative, measured at the Toronto CN Tower, to estimate tall-structure return-stroke current parameters. The approach evaluates the primary lightning return-stroke current parameters as well as reflection coefficients at major structural discontinuities.
This paper presents an application of the Electromagnetic Transient Program (ATP-EMTP) for determining the lightning current distribution within the CN Tower and the attached return-stroke channel. This ATP model takes into account current reflections within the lightning channel and the Tower. The simulation results are in good agreement with the lightning current measured at the CN Tower.
A new and simple maximum power extraction control strategy is proposed for the permanent magnet synchronous generator (PMSG) based variable speed wind energy conversion system (VSWECS). The PMSG is connected to the grid through a switch mode rectifier and a three phase voltage source (VSI) inverter. The generator side switch mode rectifier is controlled to achieve maximum power from wind. Simple estimating...
This paper provides the investigation of the performance One-Degree-of-Freedom system to be implemented in tremors patient writing device to reduce human hand tremor. The One-Degree-of-Freedom of two springs and a mass is proposed to absorb the hand vibration for patients that suffered tremors disease while writing. The performance of development device is based on drawing Archimedes spiral that done...
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