Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 10 of 10

Full-Text Articles in Engineering

Milling Of Inconel 718: An Experimental And Integrated Modeling Approach For Surface Roughness, Sadaf Zahoor, Adeel Shehzad, Muhammad Salman Habib Dec 2021

Milling Of Inconel 718: An Experimental And Integrated Modeling Approach For Surface Roughness, Sadaf Zahoor, Adeel Shehzad, Muhammad Salman Habib

Mechanical, Automotive & Materials Engineering Publications

Inconel 718, a hard-to-cut superalloy is reputed for having poor machining performance due to its low thermal conductivity. Consequently, the surface quality of the machined parts suffers. The surface roughness value must fall within the stringent limits to ensure the functional performance of the components used in aerospace and bioimplant applications. One doable way to enhance its machinability is the adequate dissipation of heat from the machining zone through efficient and ecofriendly cooling environment. With this perspective, an experimental and integrated green-response surface machiningbased- evolutionary optimization (G-RSM-EO) approach is presented during this investigation. The results are compared with two base-line …


A Hybrid Framework For Detecting And Eliminating Cyber-Attacks In Power Grids, Arshia Aflaki, Mohsen Gitizadeh, Roozbeh Razavi-Far, Vasile Palade, Ali Akbar Ghasemi Sep 2021

A Hybrid Framework For Detecting And Eliminating Cyber-Attacks In Power Grids, Arshia Aflaki, Mohsen Gitizadeh, Roozbeh Razavi-Far, Vasile Palade, Ali Akbar Ghasemi

Electrical and Computer Engineering Publications

The work described in this paper aims to detect and eliminate cyber-attacks in smart grids that disrupt the process of dynamic state estimation. This work makes use of an unsupervised learning method, called hierarchical clustering, in an attempt to create an artificial sensor to detect two different cyber-sabotage cases, known as false data injection and denial-of-service, during the dynamic behavior of the power system. The detection process is conducted by using an unsupervised learning-enhanced approach, and a decision tree regressor is then employed for removing the threat. The dynamic state estimation of the power system is done by Kalman filters, …


Generative Adversarial Network-Based Scheme For Diagnosing Faults In Cyber-Physical Power Systems, Hossein Hassani, Roozbeh Razavi-Far, Mehrdad Saif, Vasile Palade Aug 2021

Generative Adversarial Network-Based Scheme For Diagnosing Faults In Cyber-Physical Power Systems, Hossein Hassani, Roozbeh Razavi-Far, Mehrdad Saif, Vasile Palade

Electrical and Computer Engineering Publications

This paper presents a novel diagnostic framework for distributed power systems that is based on using generative adversarial networks for generating artificial knockoffs in the power grid. The proposed framework makes use of the raw data measurements including voltage, frequency, and phase-angle that are collected from each bus in the cyber-physical power systems. The collected measurements are firstly fed into a feature selection module, where multiple state-of-the-art techniques have been used to extract the most informative features from the initial set of available features. The selected features are inputs to a knockoff generation module, where the generative adversarial networks are …


The Effect Of Blade Count On Body Force Model Performance For Axial Fans, Palek Saini, Jeffrey J. Defoe Apr 2021

The Effect Of Blade Count On Body Force Model Performance For Axial Fans, Palek Saini, Jeffrey J. Defoe

Mechanical, Automotive & Materials Engineering Publications

Body force models enable inexpensive numerical simulations of turbomachinery. The approach replaces the blades with sources of momentum/energy. Such models capture a “smeared out” version of the blades’ effect on the flow, reducing computational cost. The body force model used in this paper has been widely used in aircraft engine applications. Its implementation for low speed, low solidity (few blades) turbomachines, such as automotive cooling fans, enables predictions of cooling flows and component temperatures without calibrated fan curves. Automotive cooling fans tend to have less than 10 blades, which is approximately 50% of blade counts for modern jet engine fans. …


Hvdc Circuit Breakers: A Comprehensive Review, Fazel Mohammadi, Kumars Roubehi, Masood Hajian, Kaveh Niayesh, Gevork B. Gharehpetian, Hani Saas, Hasan Ali Mohd, Vijay K. Sood Apr 2021

Hvdc Circuit Breakers: A Comprehensive Review, Fazel Mohammadi, Kumars Roubehi, Masood Hajian, Kaveh Niayesh, Gevork B. Gharehpetian, Hani Saas, Hasan Ali Mohd, Vijay K. Sood

Electrical and Computer Engineering Publications

High Voltage Direct Current (HVDC) systems are now well-integrated into AC systems in many jurisdictions. The integration of Renewable Energy Sources (RESs) is a major focus and the role of HVDC systems is expanding. However, the protection of HVDC systems against DC faults is a challenging issue that can have negative impacts on the reliable and safe operation of power systems. Practical solutions to protect HVDC grids against DC faults without a widespread power outage include (1) using DC Circuit Breakers (CBs) to isolate the faulty DC-link, (2) using a proper converter topology to interrupt the DC fault current, and/or …


Cleaning Of Floating Photovoltaic Systems: A Critical Review On Approaches From Technical And Economic Perspectives, Rafi Zahedi, Parisa Ranjbaran, Gevork B. Gharehpetian, Fazel Mohammadi, Roya Ahmadiahangar Apr 2021

Cleaning Of Floating Photovoltaic Systems: A Critical Review On Approaches From Technical And Economic Perspectives, Rafi Zahedi, Parisa Ranjbaran, Gevork B. Gharehpetian, Fazel Mohammadi, Roya Ahmadiahangar

Electrical and Computer Engineering Publications

There are some environmental factors, such as ambient temperature, dust, etc., which cause a reduction in the efficiency of Photovoltaic (PV) systems. Installation of PV panels on the water surface, commonly known as Floating Photovoltaic (FPV) systems, is one solution to employ PV panels in a cooler environment, achieve higher efficiency, and reduce water evaporation. FPV systems open up new opportunities for scaling up solar generating capacity, especially in countries with high population density and valuable lands, as well as countries with high evaporation rates and water resources deficiency. Since the FPV system is an almost new concept, its cleaning …


A Novel Stochastic Predictive Stabilizer For Dc Microgrids Feeding Cpls, Elham Kowsari, Jafar Zarei, Roozbeh Razavi-Far, Mehrdad Saif, Tomislav Dragicevic, Mohammad Hassan Khooban Apr 2021

A Novel Stochastic Predictive Stabilizer For Dc Microgrids Feeding Cpls, Elham Kowsari, Jafar Zarei, Roozbeh Razavi-Far, Mehrdad Saif, Tomislav Dragicevic, Mohammad Hassan Khooban

Electrical and Computer Engineering Publications

In this work, a novel nonlinear approach is proposed for the stabilization of microgrids (MGs) with constant power loads (CPLs). The proposed method is constructed based on the incorporation of a pseudo-extended Kalman filter (EKF) into stochastic nonlinear model predictive control (MPC). In order to achieve high-performance and optimal control in dc MGs, estimating the instantaneous power flow of the uncertain CPLs and the available power units is essential. Thus, by utilizing the advantages of the stochastic MPC and the pseudo-EKF, an effective control solution for the stabilization of dc islanded MGs with CPLs is established. This technique develops a …


Emerging Challenges In Smart Grid Cybersecurity Enhancement: A Review, Fazel Mohammadi Mar 2021

Emerging Challenges In Smart Grid Cybersecurity Enhancement: A Review, Fazel Mohammadi

Electrical and Computer Engineering Publications

In this paper, a brief survey of measurable factors affecting the adoption of cybersecurity enhancement methods in the smart grid is provided. From a practical point of view, it is a key point to determine to what degree the cyber resilience of power systems can be improved using cost-effective resilience enhancement methods. Numerous attempts have been made to the vital resilience of the smart grid against cyber-attacks. The recently proposed cybersecurity methods are considered in this paper, and their accuracies, computational time, and robustness against external factors in detecting and identifying False Data Injection (FDI) attacks are evaluated. There is …


A Comprehensive Review On Brushless Doubly-Fed Reluctance Machine, Omid Sadeghian, Sajjad Tohidi, Behnam Mohammadi-Ivatloo, Fazel Mohammadi Jan 2021

A Comprehensive Review On Brushless Doubly-Fed Reluctance Machine, Omid Sadeghian, Sajjad Tohidi, Behnam Mohammadi-Ivatloo, Fazel Mohammadi

Electrical and Computer Engineering Publications

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. The Brushless Doubly-Fed Reluctance Machine (BDFRM) has been widely investigated in numerous research studies since it is brushless and cageless and there is no winding on the rotor of this emerging machine. This feature leads to several advantages for this machine in comparison with its induction counterpart, i.e., Brushless Doubly-Fed Induction Machine (BDFIM). Less maintenance, less power losses, and also more reliability are the major advantages of BDFRM compared to BDFIM. The design complexity of its reluctance rotor, as well as flux patterns for indirect connection between the two windings mounted …


Adversarial Learning On Incomplete And Imbalanced Medical Data For Robust Survival Prediction Of Liver Transplant Patients, Ehsan Hallaji, Roozbeh Razavi-Far, Vasile Palade, Mehrdad Saif Jan 2021

Adversarial Learning On Incomplete And Imbalanced Medical Data For Robust Survival Prediction Of Liver Transplant Patients, Ehsan Hallaji, Roozbeh Razavi-Far, Vasile Palade, Mehrdad Saif

Electrical and Computer Engineering Publications

The scarcity of liver transplants necessitates prioritizing patients based on their health condition to minimize deaths on the waiting list. Recently, machine learning methods have gained popularity for automatizing liver transplant allocation systems, which enables prompt and suitable selection of recipients. Nevertheless, raw medical data often contain complexities such as missing values and class imbalance that reduce the reliability of the constructed model. This paper aims at eliminating the respective challenges to ensure the reliability of the decision-making process. To this aim, we first propose a novel deep learning method to simultaneously eliminate these challenges and predict the patients' survival …