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The following work introduces the use of the available Redundant switching states introduced by the double star four level converter topology, for its application in a medium voltage variable speed drive under a wide range of operation loads. Redundant switching states are obtained using multi-carrier phase-shifted pulse width modulation (PWM) strategy. The converter performance is…

Moderate exercise has been implemented in spaceflight programs to prevent muscle and joint damage under extreme circumstances such as microgravity. Although the physical effects of exercise have been investigated experimentally, advanced modeling and simulation techniques are powerful tools that could provide insight into the physical limitations, optimal conditions, and mechanisms that might lead to muscle…

Multitenancy isolation is a way of ensuring that the performance, stored data volume and access privileges required by one tenant and/or component does not affect other tenants and/or components. One of the conditions that can influence the varying degrees of isolation is when locking is enabled for a process or component that is being shared.…

This paper presents a novel direct torque control (DTC) strategy aimed to four-switch three-phase (FSTP) inverter-fed an interior permanent magnet synchronous machine (IPMSM), using a fuzzy logic toolbox in speed control loop. In fact, the introduced DTC approach is based on the emulation of the operation of the standard six-switch three-phase (SSTP) inverter. This fact…

In this paper, we introduce and describe a novel approach to adaptive image steganography which is combined with One-Time Pad encryption and demonstrate the software which implements this methodology. Testing using the state-of-the-art steganalysis software tool StegExpose concludes the image hiding is reliably secure and undetectable using reasonably-sized message payloads (≤25% message bits per image…

The aim of this paper is to derive and study a full-bridge three-port converter. Based on the standard design of full-bridge converter, we have modeled and derived a three port converter. The three port converter can be used in renewable energy scenarios, such as solar cells or wind turbines connected to the input port. The…

A 500 KVA Uninterruptible power supply (UPS) using Fuel Cells (FC) and super-capacitors (SCs) was studied with the worst case of 10 minutes and eight hours of interruption per day. A power management system was established to control the FC and the SCs in order to extract the hybridization benefits with a comparison between a…

Tenants associated with a cloud-hosted application seek to reduce running costs and minimize resource consumption by sharing components and resources. However, despite the benefits, sharing resources can affect tenant’s access and overall performance if one tenant abruptly experiences a significant workload, particularly if the application fails to accommodate this sudden increase in workload. In cases…

Convolutional Neural Networks (CNNs) have gained attention in recent years for their ability to perform complex machine learning tasks with high accuracy and resilient to noise of inputs. The time-consuming convolution operations of CNNs pose great challenges to both software as well as hardware designers. To achieve superior performance, a design involves careful concerns between…

This paper describes the design and analysis of a regenerative braking system for a permanent magnet synchronous motor (PMSM) drive for electric vehicle (EV) applications. First studied is the principle for electric braking control of a PMSM motor under field-oriented control (FOC). Next, the maximum braking torque in the regeneration mode as well as the…

This paper investigates the efficiency benefits of replacing the Silicon diodes of a commercial IGBT module for the main inverter application of an electric vehicle with Silicon Carbide diodes, leaving the package, operating conditions and the system unchanged. This ensures that the comparison is directly between the chip technologies without any scope for discrepancies arising…

Log-periodic antennas have high electrical characteristics over a wide frequency range. The large length of the antennas is their significant disadvantage caused by the fact that each active region consisting of several radiators operates in a narrow frequency range. To extend this range, it is proposed to use radiators with concentrated capacitive loads, providing in-phase…

Reliable operation of a power transformer with a certain load depends on the technical condition of individual construction parts and the ability to prevent defects that can cause a failure. During the lifecycle of a transformer, valuable data is constantly accumulated, which forms the basis for technical or risk assessment of the equipment. Therefore it…

This paper proposed the identification of the proper placement of UPFC (Unified Power Flow Controller) using a series of methodological numeric simulations to improve voltage stability. For this purpose, the critical zone of the system is determined, then, comparative analyses depending on different emplacements of UPFC are performed. The dynamic model of UPFC and the…

In remote measurements on large-sized objects main focus is on measuring deformations of bridge surfaces and determination of the dynamic amplification factor in particular. The proposed method estimates deflections of entire lower surface of a bridge due to placement of secondary radiators on this surface. Antenna array directivity pattern (ADP) is distorted during deflection of…

This paper presents an analysis of a parallel connection of one synchronous generator and one self-excited induction generator that feeds a resistive load and an Induction Motor. The system voltage and frequency are controlled by a voltage control loop and a speed control loop connected to synchronous generator. The induction generator speed is controlled by…

Environmental sound recognition (ESR) has become a hot topic in recent years. ESR is mainly based on machine learning (ML) and ML algorithms require first a training database. This database must comprise the sounds to be recognized and other related sounds. An ESR system needs the database during training, testing and in the production stage.…

This paper proposes the modeling and control of a Solid-State Transformer using a three-stage conversion topology. First, a rectification stage is used, where a three-phase high-voltage AC signal is converted to a DC level; this stage is then followed by a DC-DC converter, and finally an inverter is used to convert the DC into a…

A switched capacitor low-pass filter employing folded-cascode CMOS OP Amps with a dynamic switching bias circuit capable of processing video signals, which enables low power consumption, and operation in wide bandwidths and low power supply voltages, is proposed. In this filter, charge transfer operations through two-phase clock pulses during the on-state period of the OP…

This paper presents the modelling and analysis of permanent magnet synchronous generator (PMSG) which are used in direct driven small scale wind turbines. The 3 kW PM generator which is driven directly without gear system is analyzed by Ansoft Maxwell 2D RMxprt. The performance analysis of generator includes the cogging torque in two teeth, induced…

This paper proposes extended-range high-speed control for an IPMSM drive system. A simple real-time tuning flux-weakening control algorithm is proposed and implemented to control an IPMSM drive system in a wide variable speed range, from 3 r/min up to 2700 r/min. This flux-weakening control algorithm does not require any motor parameters and only needs simple…

Over the years, wind loading codes has been a crucial tool in determining design wind loads on buildings. Due to the limitations of these codes especially in height, wind tunnel testing is recommended as the best approach in predicting wind flow around buildings but carrying out wind tunnel testing in the preliminary as well as…

New multimedia applications such as mobile video, high-quality Internet video or digital television requires high-performance encoding of video signals to meet technical constraints such as runtime, bandwidth or latency. Video coding standard h.265 HEVC (High Efficiency Video Coding) was developed by JCT-VC to replace the MPEG-2, MPEG-4 and h.264 codecs and to respond to these…

This paper analyzed wind loading responses of Aluminum Wall cladding panels in Tall Building using Ikeja Lagos State Nigeria. The wind loads were calculated according to Standard and Specification From BS6399-2:1997 Using the wind speed data of Lagos state Nigeria and finite element analysis, we predicted the responses of these Aluminum wall Cladding panels to…

Energy efficiency is a salient design consideration for stabilization mechanisms when assembled on a battery-powered vehicle. In this paper we study the implementation of a two-axis gimbal with passive revolute joints for motion isolation of an inertially stabilized platform (ISP) mounted on a host vehicle. The objective is for the ISP to maintain a steady…