A comprehensive review on brushless doubly-fed reluctance machine

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 on the stator including power winding and control winding, have restricted the development of this machine technology. In the literature, there is not a comprehensive review of the research studies related to BDFRM. In this paper, the previous research studies are reviewed from different points of view, such as operation, design, control, transient model, dynamic model, power factor, Maximum Power Point Tracking (MPPT), and losses. It is revealed that the BDFRM is still evolving since the theoretical results have shown that this machine operates efficiently if it is well-designed

A comprehensive review on brushless doubly-fed reluctance machine

© 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 on the stator including power winding and control winding, have restricted the development of this machine technology. In the literature, there is not a comprehensive review of the research studies related to BDFRM. In this paper, the previous research studies are reviewed from different points of view, such as operation, design, control, transient model, dynamic model, power factor, Maximum Power Point Tracking (MPPT), and losses. It is revealed that the BDFRM is still evolving since the theoretical results have shown that this machine operates efficiently if it is well-designed

Improving Residential Load Disaggregation for Sustainable Development of Energy via Principal Component Analysis

The useful planning and operation of the energy system requires a sustainability assessment of the system, in which the load model adopted is the most important factor in sustainability assessment. Having information about energy consumption patterns of the appliances allows consumers to manage their energy consumption efficiently. Non-intrusive load monitoring (NILM) is an effective tool to recognize power consumption patterns from the measured data in meters. In this paper, an unsupervised approach based on dimensionality reduction is applied to identify power consumption patterns of home electrical appliances. This approach can be utilized to classify household activities of daily life using data measured from home electrical smart meters. In the proposed method, the power consumption curves of the electrical appliances, as high-dimensional data, are mapped to a low-dimensional space by preserving the highest data variance via principal component analysis (PCA). In this paper, the reference energy disaggregation dataset (REDD) has been used to verify the proposed method. REDD is related to real-world measurements recorded at low-frequency. The presented results reveal the accuracy and efficiency of the proposed method in comparison to conventional procedures of NILM

Direct probabilistic load flow in radial distribution systems including wind farms: An approach based on data clustering

© 2018 by the authors. The ongoing study aims to establish a direct probabilistic load flow (PLF) for the analysis of wind integrated radial distribution systems. Because of the stochastic output power of wind farms, it is very important to find a method which can reduce the calculation burden significantly, without having compromising the accuracy of results. In the proposed approach, a K-means based data clustering algorithm is employed, in which all data points are bunched into desired clusters. In this regard, probable agents are selected to run the PLF algorithm. The clustered data are used to employ the Monte Carlo simulation (MCS) method. In this paper, the analysis is performed in terms of simulation run-time. Also, this research follows a two-fold aim. In the first stage, the superiority of data clustering-based MCS over the unsorted data MCS is demonstrated properly. Moreover, the impact of data clustering-based MCS and unsorted data-based MCS is investigated using an indirect probabilistic forward/backward sweep (PFBS) method. Thus, in the second stage, the simulation run-time comparison is carried out rigorously between the proposed direct PLF and the indirect PFBS method to examine the computational burden effects. Simulation results are exhibited on the IEEE 33-bus and 69-bus radial distribution systems

Alteration in CD8+ T cell subsets in enterovirus-infected patients: An alarming factor for type 1 diabetes mellitus

Type 1 diabetes is a multi-factorial disease that can develop due to the combination of genetic and environmental factors. Viruses, particularly enteroviruses, are major environmental candidates in the pathogenesis of type 1 diabetes, even though the mechanisms of pathogenicity of these viruses and their effects on the immune system have not been understood very well yet. Previous studies show that any imbalance in the population of different lymphocyte subsets could develop autoimmune diseases. Our theory is that enteroviral infection causes an impairment in the distribution of lymphocyte subtypes and consequently results in the diabetes onset in some individuals. Therefore, in this project, we evaluated the distribution of T CD8+ lymphocytes and their subsets in type 1 diabetes patients. This study was conducted to investigate the relationship between enteroviral infection and type 1 diabetes mellitus in an Iranian population, and suggestion a predicting approach for susceptible subjects

Alteration in CD8+T cell subsets in enterovirus-infected patients: An alarming factor for type 1 diabetes mellitus

Type 1 diabetes is a multi-factorial disease that can develop due to the combination of genetic and environmental factors. Viruses, particularly enteroviruses, are major environmental candidates in the pathogenesis of type 1 diabetes, even though the mechanisms of pathogenicity of these viruses and their effects on the immune system have not been understood very well yet. Previous studies show that any imbalance in the population of different lymphocyte subsets could develop autoimmune diseases. Our theory is that enteroviral infection causes an impairment in the distribution of lymphocyte subtypes and consequently results in the diabetes onset in some individuals. Therefore, in this project, we evaluated the distribution of T CD8+ lymphocytes and their subsets in type 1 diabetes patients. This study was conducted to investigate the relationship between enteroviral infection and type 1 diabetes mellitus in an Iranian population, and suggestion a predicting approach for susceptible subjects. © 201

Generation Units Maintenance in Combined Heat and Power Integrated Systems Using the Mixed Integer Quadratic Programming Approach

Yearly generation maintenance scheduling (GMS) of generation units is important in each system such as combined heat and power (CHP)-based systems to decrease sudden failures and premature degradation of units. Imposing repair costs and reliability deterioration of system are the consequences of ignoring the GMS program. In this regard, this research accomplishes GMS inside CHP-based systems in order to determine the optimal intervals for predetermined maintenance required duration of CHPs and other units. In this paper, cost minimization is targeted, and violation of units’ technical constraints like feasible operation region of CHPs and power/heat demand balances are avoided by considering related constraints. Demand-response-based short-term generation scheduling is accomplished in this paper considering the maintenance intervals obtained in the long-term plan. Numerical simulation is performed and discussed in detail to evaluate the application of the suggested mixed-integer quadratic programming model that implemented in the General Algebraic Modeling System software package for optimization. Numerical simulation is performed to justify the model effectiveness. The results reveal that long-term maintenance scheduling considerably impacts short-term generation scheduling and total operation cost. Additionally, it is found that the demand response is effective from the cost perspective and changes the generation schedul

Normal Computed Tomography and Radiographic Study of the Nasal Cavity and Paranasal Sinuses in Shal Sheep (Ovis arries)

Understanding anatomical structures from the past to the present has been one of the guidelines for advancing medical and veterinary science worldwide. The lack of comprehensive information on the anatomy of the paranasal sinuses and the Shal sheep nasal cavity (Ovis aries) encouraged us to write this article. Computed tomography (CT) scan is a method that shows different parts of the body without superimposition of adjacent structures. Radiographic imaging also gives very high-resolution images of bones to examine bone structures. Paranasal sinuses of Shal sheep were composed of frontal, maxillary, lacrimal, and palatine sinuses, and the nasal sinuses were composed of dorsal, and middle nasal sinuses, which were identified and labeled in keeping with cheek teeth as landmarks. The width of the frontal bone and length of the nasal cavity at the level of the 6th cheek tooth were 7 ± 0.3 and 13 ± 0.8 cm, respectively. The volumes of both the right and left sinuses were measured automatically, and the accurate location of sinuses, canals, nasal folds, conchae, and meatuses, and connections between different parts of the nasal cavity and paranasal sinuses were described. The volume of the frontal, maxillary, and palatine sinuses were 279.3 ± 16.4, 80.6 ± 2.6, and 13.5 ± 0.2 cm3, respectively. Frontal, maxillary, and lacrimal sinuses were observed like other ruminants. But the palatine sinus in this breed was not present in the Egyptian sheep, Saanen, and Markhz goats. Also, unlike Sanan and Markhz goats and like Egyptian sheep, ventral nasal sinus was not observed in this breed