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A Support Vector Machine (SVM) based approach for microgrid islanding decision and control is investigated. The IEEE 13-feeder system is modified and serves as the microgrid model connected to Kundur four-machine two-area system that models the main transmission grid. A representative data set is obtained through simulations in MATLAB/Simulink considering multiple typical scenarios with or without...
The DC power flow model is in widespread utilization in electricity-market applications and contingency analysis. The presented versions of this model can be classified into two categories: state-dependent, or Hot-Start, models and state-independent, or Cold-Start, models. A reasonable accuracy is reported in the literature regarding Hot-Start models as they take into account branch losses and bus...
Low power factors are considered one of the pressing issues in the distribution system planning and operation particularly at countries where a monetary cost's scheme of the reactive power usage is not applied. Regulations, financial penalties and incentives, and technical solutions have all been used to improve low power factor levels. In this paper, a study and comparisons between several low power...
This paper presents an improved stochastic simulation method for calculating current dependent energy losses in distribution networks. The method is based on power load curves and integrates the stochastic nature of the load curves with power and voltage covariance matrices. The method reduces calculation effort using the factor analysis of covariance matrices and provides a few quantities needed...
This paper presents a novel method based on sparse representation classification (SRC) and random dimensionality reduction projection (RDRP) to classify electric power system fault types in real time. Each testing fault sample is firstly represented as an overcomplete sparse linear combination of training fault samples. Then RDRP is applied to extract fault features with reduced dimensionality and...
This paper presents model for Modular Multilevel Converter (MMC) in phasor format, which is convenient for power flow and parameter studies. The model is derived in rotating dq coordinate frame, and the coordinate frame at double the fundamental frequency, in steady-state. A substantial analytical basis is presented in order to facilitate direct mathematical manipulations of non-linear terms in the...
In recent years, the damage caused by botnets has increased and become a big problem. To solve this problem, we proposed a method to detect unjust C&C servers by using Hayashi's quantification theory class II. This method is able to detect unjust C&C servers, even if they are not included in a blacklist. However, it was predicted that the detection rate for this method decreases with...
The revolution of online learning brings great opportunities to millions of learners. However, the size of the learner population and the heterogeneity of the learners' backgrounds make conventional one-size-fits-all pedagogies inappropriate. We propose a conceptual model -- educational resource linking with the goal of satisfying various learning needs by building a rich platform integrating abundant...
This study proposes an Intelligent Tutor System for assessing slide presentations from novice undergraduate students. To develop such system, two learner models (rule based model and clustering model) were built using 80 presentations graded by three human experts. An experiment to determine the best learner model and students' perception was carried out using 51 presentations uploaded by students...
Nonlinearity of power flow equations is one of the major underlying factors in a power systems operation complexity. The need for a robust and less complex models rises in a volatile, dynamic and real time scenario. This paper introduces new empirical models using multivariate linear regression (MLR) methods with least squares for both real and reactive branch flows. The models do not make prior assumptions...
Floating-point arithmetic may introduce failures of the numerical reproducibility between a priori similar sequential and parallel executions of HPC simulation. We present how to apply some existing techniques to part of hydrodynamic finite element simulations. We analyze how easy these techniques allow us to recover its numerical reproducibility.
The Phase-domain (or Universal) line and cable model (ULM) is one of the most advanced in its class. This model is synthesized from frequency-domain transmission line relations in three stages involving rational fitting, state-space analysis and numeric integration. Each one of these stages implies an approximation and this paper presents an evaluation their impact on the accuracy of the final model...
The future power grid will need to incorporate systems and processes with a higher degree of variability and randomness due to the penetration of renewable energy resources and the increase of energy demand. Forecasting variables in a more uncertain environment poses new challenges and revisions of the existing forecasting methodologies will have to be made to maintain forecasting accuracy. This paper...
This paper presents novel means for estimating the polynomial static nonlinearity coefficients of a Wiener system in absence of a priori information about the linear block. To capture the system structure, the identification is performed with respect to a Volterra series model, whose kernels are parameterized in terms of Laguerre functions. A property of the resulting Volterra-Laguerre model is exploited...
Metabolic equivalent of task (MET) indicates the intensity of physical activities. This measurement is used in providing physical activity intervention in many chronic illnesses such as coronary heart disease, type-2 diabetes, and cancer. Due to the small size, portability, low power consumption, and low cost, wearable motion sensors are widely used to estimate MET values. However, one major obstacle...
Active triangulation has been successfully applied in numerous applications such as distance measurement, profile inspections and pose estimation in robotics. Its accuracy depends on many factors with locating laser centroid being one of them. The error generated in locating the laser centroid within the image is propagated to the system output with consequences in decreasing performance. In this...
This paper shows part of the work carried out to develop parallel versions of the SLICOT routines for model reduction of stable systems. In particular, the routines that have been parallelised are those based on the solution of Lyapunov equations. The goal is to be able to work with larger unreduced models and also to obtain better performance in the reduction process. New routines have been developed...
Four models are used to estimate the hourly solar radiation on 15 pieces of different tilted photovoltaic (PV) modules in Wuhan, China based on power and solar radiation data during a whole year. The optimum tilt angle (OTA) in Wuhan for yearly and semi-yearly adjustment was determined. Then it was determined that the best mode is the tilt angle of PV module adjusted every half a year. In semi-yearly...
The accurate value of the electric machine parameters is required to design an efficient current controller and torque controller in the permanent magnet synchronous machine (PMSM) drive system. The values of these parameters are not constant but vary with the operation condition. The stator winding resistance and rotor flux linkage are affected by the temperature. Inductances are changed according...
Two of the three most important causes of Information Technology projects failure have been related to a poor resource estimation. In average, software developers expend from 30% to 40% more effort than is estimated. Because that no single technique to estimate software development effort is best for all situations, it is important to propose new models to compare their results and then generate more...
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