Search results for: induction educators
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1442

Search results for: induction educators

1382 [Keynote Talk]: A Blueprint for an Educational Trajectory: The Power of Discourse in Constructing “Naughty” and “Adorable” Kindergarten Students

Authors: Fernanda T. Orsati, Julie Causton

Abstract:

Discursive practices enacted by educators in kindergarten create a blueprint for how the educational trajectories of students with disabilities are constructed. This two-year ethnographic case study critically examine educators’ relationships with students considered to present challenging behaviors in one kindergarten classroom located in a predominantly White middle-class school district in the Northeast of the United States. Focusing on the language and practices used by one special education teacher and three teaching assistants, this paper analyzes how teacher responses to students’ behaviors constructs and positions students over one year of kindergarten education. Using a critical discourse analysis, it shows that educators understand students’ behaviors as a deficit and needing consequences. This study highlights how educators’ responses reflect students' individual characteristics including family background, socioeconomics and ability status. This paper offers in-depth analysis of two students’ stories, which evidenced that the language used by educators amplifies the social positioning of students within the classroom and creates a foundation for who they are constructed to be. Through exploring routine language and practices, this paper demonstrates that educators outlined a blueprint of kindergartners, which positioned students as learners in ways that became the ground for either a limited or a promising educational pathway for them.

Keywords: behavior, early education, special education, critical discourse analysis

Procedia PDF Downloads 308
1381 Risk Factors for Post-Induction Hypotension Among Elderly Patients Undergoing Elective Non-Cardiac Surgery Under General Anesthesia

Authors: Karuna Sutthibenjakul, Sunisa Chatmongkolchart

Abstract:

Background: Postinduction hypotension is common and occurs more often in elderly patients. We aimed to determine risk factors for hypotension after induction among elderly patients (aged 65 years and older) who underwent elective non-cardiac surgery under general anesthesia. Methods: This cohort study analyzed from 580 data between December 2017 and July 2018 at a tertiary university hospital in south of Thailand. Hypotension is defined as more than 30% decrease mean arterial pressure from baseline after induction within 20 minutes or the use of vasopressive agent to treat low blood pressure. Intraoperative parameters were blood pressure and heart rate at T0, TEI, T5, T10, T15 and T20 (immediately after arrival at operating room, time after intubation, 5, 10, 15 and 20 minutes after intubation) respectively. Results: The median age was 72.5 (68, 78) years. A prevalence of post-induction hypotension was 64.8%. The highest prevalence (39.7%) was at 15 minutes after intubation. The association of post-induction hypotension is rising with diuretic drug as preoperative medication (P-value=0.016), hematocrit level (P-value=0.031) and the degree of hypertension immediately after arrival at operating room (P-value<0.001). Increasing fentanyl dosage during induction was associated with hypotension at intubation time (P-value<0.01) and 5 minutes after intubation (P-value<0.001). There was no statistically significant difference in the increasing propofol dosage. Conclusion: The degree of hypertension immediately after arrival at operating room and increasing fentanyl dosage were a significant risk factors for postinduction hypotension in elderly patients.

Keywords: risk factors, post-induction, hypotension, elderly

Procedia PDF Downloads 131
1380 Comparison of the Thermal Characteristics of Induction Motor, Switched Reluctance Motor and Inset Permanent Magnet Motor for Electric Vehicle Application

Authors: Sadeep Sasidharan, T. B. Isha

Abstract:

Modern day electric vehicles require compact high torque/power density motors for electric propulsion. This necessitates proper thermal management of the electric motors. The main focus of this paper is to compare the steady state thermal analysis of a conventional 20 kW 8/6 Switched Reluctance Motor (SRM) with that of an Induction Motor and Inset Permanent Magnet (IPM) motor of the same rating. The goal is to develop a proper thermal model of the three types of models for Finite Element Thermal Analysis. JMAG software is used for the development and simulation of the thermal models. The results show that the induction motor is subjected to more heating when used for electric vehicle application constantly, compared to the SRM and IPM.

Keywords: electric vehicles, induction motor, inset permanent magnet motor, loss models, switched reluctance motor, thermal analysis

Procedia PDF Downloads 224
1379 Cepstrum Analysis of Human Walking Signal

Authors: Koichi Kurita

Abstract:

In this study, we propose a real-time data collection technique for the detection of human walking motion from the charge generated on the human body. This technique is based on the detection of a sub-picoampere electrostatic induction current, generated by the motion, flowing through the electrode of a wireless portable sensor attached to the subject. An FFT analysis of the wave-forms of the electrostatic induction currents generated by the walking motions showed that the currents generated under normal and restricted walking conditions were different. Moreover, we carried out a cepstrum analysis to detect any differences in the walking style. Results suggest that a slight difference in motion, either due to the individual’s gait or a splinted leg, is directly reflected in the electrostatic induction current generated by the walking motion. The proposed wireless portable sensor enables the detection of even subtle differences in walking motion.

Keywords: human walking motion, motion measurement, current measurement, electrostatic induction

Procedia PDF Downloads 344
1378 Fault Diagnosis in Induction Motors Using Discrete Wavelet Transform

Authors: K. Yahia, A. Titaouine, A. Ghoggal, S. E. Zouzou, F. Benchabane

Abstract:

This paper deals with the problem of stator faults diagnosis in induction motors. Using the discrete wavelet transform (DWT) for the current Park’s vector modulus (CPVM) analysis, the inter-turn short-circuit faults diagnosis can be achieved. This method is based on the decomposition of the CPVM signal, where wavelet approximation and detail coefficients of this signal have been extracted. The energy evaluation of a known bandwidth detail permits to define a fault severity factor (FSF). This method has been tested through the simulation of an induction motor using a mathematical model based on the winding-function approach. Simulation, as well as experimental, results show the effectiveness of the used method.

Keywords: Induction Motors (IMs), inter-turn short-circuits diagnosis, Discrete Wavelet Transform (DWT), Current Park’s Vector Modulus (CPVM)

Procedia PDF Downloads 553
1377 Stator Short-Circuits Fault Diagnosis in Induction Motors

Authors: K. Yahia, M. Sahraoui, A. Guettaf

Abstract:

This paper deals with the problem of stator faults diagnosis in induction motors. Using the discrete wavelet transform (DWT) for the current Park’s vector modulus (CPVM) analysis, the inter-turn short-circuit faults diagnosis can be achieved. This method is based on the decomposition of the CPVM signal, where wavelet approximation and detail coefficients of this signal have been extracted. The energy evaluation of a known bandwidth detail permits to define a fault severity factor (FSF). This method has been tested through the simulation of an induction motor using a mathematical model based on the winding-function approach. Simulation, as well as experimental results, show the effectiveness of the used method.

Keywords: induction motors (IMs), inter-turn short-circuits diagnosis, discrete wavelet transform (DWT), Current Park’s Vector Modulus (CPVM)

Procedia PDF Downloads 457
1376 Evaluation of Progesterone and Estradiol17-ß Levels in Ewes Induced with Different Methods

Authors: E. Sinem Ozdemir Salci, Nazmiye Gunes, Guven Ozkaya, Gulsen Goncagul, Kamil Seyrek Intas

Abstract:

The aim of this study was to show the effects of progesterone and estrogen concentrations in ewes induced with different induction of parturition methods. Twenty-four healthy ewes (n=24) on 138th gestation day were randomly separated according to induction methods (group I (n=6), (0.09% NaCl), group II (n=6) (dexamethasone, 16 mg im.), group III (n=6) (aglepristone 5mg/kg sc.) and group IV (n=6) (aglepristone, 2,5 mg/kg sc.+dexamethasone 8 mg im.). The blood samples of the ewes were collected at 12 hours intervals from induction time to the postpartum 2nd day in order to determine progesterone and estradiol 17-ß levels. These hormone concentrations were determined by ELISA, and obtained results were statistically analyzed with Kruskal Wallis and Dunn tests between the groups, and Friedman and Wilcoxon test within the groups. The results pointed out that there was no significant difference within the groups in terms of estradiol 17-ß (group 1, p=0.508; group 2, p=0.054; group 3, p=0.672; group 4, p=0,170). And there was only a significant difference at 138th day (p=0,019) between groups II and IV (p=0,010). There was a significant difference in terms of progesterone concentration within group 1, 2 and 4 (p=0.000). And there was a significant difference at all times except 138th day between the groups (p<0.05). As a conclusion, the induction of parturition methods could be performed successfully. These methods have no effect on estradiol 17-ß concentration but also make changings on progesterone concentrations as in groups 3 and 4.

Keywords: ewe, estradiol 17-ß, induction of parturition, progesterone

Procedia PDF Downloads 216
1375 The Manufacturing of Metallurgical Grade Silicon from Diatomaceous Silica by an Induction Furnace

Authors: Shahrazed Medeghri, Saad Hamzaoui, Mokhtar Zerdali

Abstract:

The metallurgical grade silicon (MG-Si) is obtained from the reduction of silica (SiO2) in an induction furnace or an electric arc furnace. Impurities inherent in reduction process also depend on the quality of the raw material used. Among the applications of the silicon, it is used as a substrate for the photovoltaic conversion of solar energy and this conversion is wider as the purity of the substrate is important. Research is being done where the purpose is looking for new methods of manufacturing and purification of silicon, as well as new materials that can be used as substrates for the photovoltaic conversion of light energy. In this research, the technique of production of silicon in an induction furnace, using a high vacuum for fusion. Diatomaceous Silica (SiO2) used is 99 mass% initial purities, the carbon used is 6N of purity and the particle size of 63μm as starting materials. The final achieved purity of the material was above 50% by mass. These results demonstrate that this method is a technically reliable, and allows obtaining a better return on the amount 50% of silicon.

Keywords: induction furnaces, amorphous silica, carbon microstructure, silicon

Procedia PDF Downloads 404
1374 Simulation Study of a Fault at the Switch on the Operation of the Doubly Fed Induction Generator Based on the Wind Turbine

Authors: N. Zerzouri, N. Benalia, N. Bensiali

Abstract:

This work is devoted to an analysis of the operation of a doubly fed induction generator (DFIG) integrated with a wind system. The power transfer between the stator and the network is carried out by acting on the rotor via a bidirectional signal converter. The analysis is devoted to the study of a fault in the converter due to an interruption of the control of a semiconductor. Simulation results obtained by the MATLAB / Simulink software illustrate the quality of the power generated at the default.

Keywords: doubly fed induction generator (DFIG), wind power generation, back to back PWM converter, default switching

Procedia PDF Downloads 465
1373 Speed Power Control of Double Field Induction Generator

Authors: Ali Mausmi, Ahmed Abbou, Rachid El Akhrif

Abstract:

This research paper aims to reduce the chattering phenomenon due to control by sliding mode control applied on a wind energy conversion system based on the doubly fed induction generator (DFIG). Our goal is to offset the effect of parametric uncertainties and come as close as possible to the dynamic response solicited by the control law in the ideal case and therefore force the active and reactive power generated by the DFIG to accurately follow the reference values which are provided to it. The simulation results using Matlab / Simulink demonstrate the efficiency and performance of the proposed technique while maintaining the simplicity of control by first order sliding mode.

Keywords: control of speed, correction of the equivalent command, induction generator, sliding mode

Procedia PDF Downloads 377
1372 The Effect of Dynamic Eccentricity on the Stator Current Spectrum of 550 kW Induction Motor

Authors: Saleh Elawgali

Abstract:

In order to present the effect of the dynamic eccentricity on the stator currents of squirrel cage induction machines, the current spectrums of a 550 kW induction motor was calculated for the cases of full symmetry and dynamic eccentricity. The calculations presented in this paper are based on the Poly-Harmonic Model accounting for static and dynamic eccentricity, stator and rotor slotting, parallel branches as well as cage asymmetry. The calculations were followed by Fourier analysis of the stator currents in steady state operation. The paper presents the stator current spectrums for full symmetry and dynamic eccentricity cases, and demonstrates the harmonics present in each case. The effect of dynamic eccentricity is demonstrating via comparing the current spectrums related to dynamic eccentricity cases with the full symmetry one.

Keywords: current spectrum, dynamic eccentricity, harmonics, Induction machine, slot harmonic zone.

Procedia PDF Downloads 399
1371 Diagnosis of Static Eccentricity in 400 kW Induction Machine Based on the Analysis of Stator Currents

Authors: Saleh Elawgali

Abstract:

Current spectrums of a four pole-pair, 400 kW induction machine were calculated for the cases of full symmetry and static eccentricity. The calculations involve integration of 93 electrical plus four mechanical ordinary differential equations. Electrical equations account for variable inductances affected by slotting and eccentricities. The calculations were followed by Fourier analysis of the stator currents in steady state operation. Zooms of the current spectrums, around the 50 Hz fundamental harmonic as well as of the main slot harmonic zone, were included. The spectrums included refer to both calculated and measured currents.

Keywords: diagnostic, harmonic, induction machine, spectrum

Procedia PDF Downloads 523
1370 Astragaioside IV Inhibits Type2 Allergic Contact Dermatitis in Mice and the Mechanism Through TLRs-NF-kB Pathway

Authors: Xiao Wei, Dandan Sheng, Xiaoyan Jiang, Lili Gui, Huizhu Wang, Xi Yu, Hailiang Liu, Min Hong

Abstract:

Objective: Mice Type2 allergic contact dermatitis was utilized in this study to explore the effect of AS-IV on Type 2 allergic inflammatory. Methods: The mice were topically sensitized on the shaved abdomens with 1.5% FITC solution on abdominal skin in the day 1 and day 2 and elicited on the right ear with 0.5% FITC solution at day 6. Mice were treated with either AS-IV or normal saline from day 1 to day 5 (induction phase). Auricle swelling was measured 24 h after the elicitation. Ear pathohistological examination was carried out by HE staining. IL-4\IL-13, and IL-9 levels of ear tissue were detected by ELISA. Mice were treated with AS-IV at the initial stage of induction phase, ear tissue was taked at day 3.TSLP level of ear tissue was detected by ELISA and TSLPmRNA\NF-kBmRNA\TLRs(TLR2\TLR3\TLR8\TLR9)mRNA were detected by PCR. Results: AS-IV induction phase evidently inhibited the auricle inflam-mation of the models; pathohistological results indicated that AS-IV induction phase alleviated local edema and angiectasis of mice models and reduced lymphocytic infiltration. AS-IV induction phase markedly decreased IL-4\IL-13, and IL-9 levels in ear tissue. Moreover, at the initial stage of induction pha-se, AS-IV significantly reduced TSLP\TSLPmRNA\NF-kBmRNA\TLR2mRNA\TLR8 mRNA levels in ear tissue. Conclusion: Administration with AS-IV in induction phase could inhibit Type 2 allergic contact dermatitis in mice significantly, and the mechanism may be related with regulating TSLP through TLRs-NF-kB pathway.

Keywords: Astragaioside IV, allergic contact dermatitis, TSLP, interleukin-4, interleukin-13, interleukin-9

Procedia PDF Downloads 431
1369 Study of the Protection of Induction Motors

Authors: Bencheikh Abdellah

Abstract:

In this paper, we present a mathematical model dedicated to the simulation breaks bars in a three-phase cage induction motor. This model is based on a mesh circuit representing the rotor cage. The tested simulation allowed us to demonstrate the effectiveness of this model to describe the behavior of the machine in a healthy state, failure.

Keywords: AC motors, squirrel cage, diagnostics, MATLAB, SIMULINK

Procedia PDF Downloads 438
1368 High-Frequency Half Bridge Inverter Applied to Induction Heating

Authors: Amira Zouaoui, Hamed Belloumi, Ferid Kourda

Abstract:

This paper presents the analysis and design of a DC–AC resonant converter applied to induction heating. The proposed topology based on the series-parallel half-bridge resonant inverter is described. It can operate with Zero-Voltage Switching (ZVS). At the resonant frequency, the secondary current is amplified over the heating coil with small switching angle, which keeps the reactive power low and permits heating with small current through the resonant inductor and the transformer. The operation and control principle of the proposed high frequency inverter is described and verified through simulated and experimental results.

Keywords: induction heating, inverter, high frequency, resonant

Procedia PDF Downloads 464
1367 Emulation of a Wind Turbine Using Induction Motor Driven by Field Oriented Control

Authors: L. Benaaouinate, M. Khafallah, A. Martinez, A. Mesbahi, T. Bouragba

Abstract:

This paper concerns with the modeling, simulation, and emulation of a wind turbine emulator for standalone wind energy conversion systems. By using emulation system, we aim to reproduce the dynamic behavior of the wind turbine torque on the generator shaft: it provides the testing facilities to optimize generator control strategies in a controlled environment, without reliance on natural resources. The aerodynamic, mechanical, electrical models have been detailed as well as the control of pitch angle using Fuzzy Logic for horizontal axis wind turbines. The wind turbine emulator consists mainly of an induction motor with AC power drive with torque control. The control of the induction motor and the mathematical models of the wind turbine are designed with MATLAB/Simulink environment. The simulation results confirm the effectiveness of the induction motor control system and the functionality of the wind turbine emulator for providing all necessary parameters of the wind turbine system such as wind speed, output torque, power coefficient and tip speed ratio. The findings are of direct practical relevance.

Keywords: electrical generator, induction motor drive, modeling, pitch angle control, real time control, renewable energy, wind turbine, wind turbine emulator

Procedia PDF Downloads 234
1366 Application of Granular Computing Paradigm in Knowledge Induction

Authors: Iftikhar U. Sikder

Abstract:

This paper illustrates an application of granular computing approach, namely rough set theory in data mining. The paper outlines the formalism of granular computing and elucidates the mathematical underpinning of rough set theory, which has been widely used by the data mining and the machine learning community. A real-world application is illustrated, and the classification performance is compared with other contending machine learning algorithms. The predictive performance of the rough set rule induction model shows comparative success with respect to other contending algorithms.

Keywords: concept approximation, granular computing, reducts, rough set theory, rule induction

Procedia PDF Downloads 531
1365 Electro Magnetic Tractor (E. M. Tractor)

Authors: Sijo Varghese

Abstract:

A space craft (E. M. Tractor) which is intended to deflect or tug the asteroids which possesses threat towards the planets is the whole idea behind this paper. In this case "Electro Magnetic Induction" is used where it is known that when two separate circuits are connected to the electro magnet and on application of electric current through the one circuit in to the coil induces magnetic fields which repels the other circuit.( Faraday's law of Electromagnetic Induction). Basically a Spacecraft is used to attach a large sheet of aluminum on to the surface of the asteroid, the Spacecraft acts as an electro magnet and the induced magnetic field would eventually repel the aluminum intern repelling the asteroid. This method would take less time as compared to use of gravity( which requires a larger spacecraft and process will take a long time).

Keywords: asteroids, electro magnetic induction, gravity, electro magnetic tractor

Procedia PDF Downloads 492
1364 Towards the Use of Innovative Teaching Methodologies in Nursing Education : A South African Study

Authors: R. Bhagwan, M. Subbhan

Abstract:

Nursing is a very challenging field in South Africa and due to the burden of disease it is critical that nursing students are prepared with the adequate knowledge and skills to deliver effective patient care. Despite this very little research has been done on the teaching strategies used by nurse educators to teach nursing students. It is in this context that a survey of all nurse educators at Nursing Colleges and Universities in Kwa-Zulu Natal was undertaken (n=300) to explore what current pedagogical strategies were being used and which more creative methodologies should be implemented in relation to specific nursing content. Findings revealed that most nurse educators still utlize the lecture approach, but although believe other methodologies such as e-learning are important have not done so because of inadequate training. The recommendations made are that more creative pedagogical strategies such as simultation, portfoloios and case studies be adopted.

Keywords: creative, teaching methodologies, dydactic, nursing

Procedia PDF Downloads 603
1363 Educators’ Adherence to Learning Theories and Their Perceptions on the Advantages and Disadvantages of E-Learning

Authors: Samson T. Obafemi, Seraphin D. Eyono-Obono

Abstract:

Information and Communication Technologies (ICTs) are pervasive nowadays, including in education where they are expected to improve the performance of learners. However, the hope placed in ICTs to find viable solutions to the problem of poor academic performance in schools in the developing world has not yet yielded the expected benefits. This problem serves as a motivation to this study whose aim is to examine the perceptions of educators on the advantages and disadvantages of e-learning. This aim will be subdivided into two types of research objectives. Objectives on the identification and design of theories and models will be achieved using content analysis and literature review. However, the objective on the empirical testing of such theories and models will be achieved through the survey of educators from different schools in the Pinetown District of the South African Kwazulu-Natal province. SPSS is used to quantitatively analyse the data collected by the questionnaire of this survey using descriptive statistics and Pearson correlations after assessing the validity and the reliability of the data. The main hypothesis driving this study is that there is a relationship between the demographics of educators’ and their adherence to learning theories on one side, and their perceptions on the advantages and disadvantages of e-learning on the other side, as argued by existing research; but this research views these learning theories under three perspectives: educators’ adherence to self-regulated learning, to constructivism, and to progressivism. This hypothesis was fully confirmed by the empirical study except for the demographic factor where teachers’ level of education was found to be the only demographic factor affecting the perceptions of educators on the advantages and disadvantages of e-learning.

Keywords: academic performance, e-learning, learning theories, teaching and learning

Procedia PDF Downloads 273
1362 Investigation of Grid Supply Harmonic Effects in Wound Rotor Induction Machines

Authors: Nur Sarma, Paul M. Tuohy, Siniša Djurović

Abstract:

This paper presents an in-depth investigation of the effects of several grid supply harmonic voltages on the stator currents of an example wound rotor induction machine. The observed effects of higher order grid supply harmonics are identified using a finite element time stepping transient model, as well as a time-stepping electromagnetic model. In addition, a number of analytical equations to calculate the spectral content of the stator currents are presented in the paper. The presented equations are validated through comparison with the obtained spectra predicted using the finite element and electromagnetic models. The presented study provides a better understanding of the origin of supply harmonic effects identified in the stator currents of the example wound rotor induction machine. Furthermore, the study helps to understand the effects of higher order supply harmonics on the harmonic emissions of the wound rotor induction machine.  

Keywords: wound rotor induction machine, supply harmonics, current spectrum, power spectrum, power quality, harmonic emmisions, finite element analysis

Procedia PDF Downloads 178
1361 CDM-Based Controller Design for High-Frequency Induction Heating System with LLC Tank

Authors: M. Helaimi, R. Taleb, D. Benyoucef, B. Belmadani

Abstract:

This paper presents the design of a polynomial controller with coefficient diagram method (CDM). This controller is used to control the output power of high frequency resonant inverter with LLC tank. One of the most important problems associated with the proposed inverter is achieving ZVS operating during the induction heating process. To overcome this problem, asymmetrical voltage cancellation (AVC) control technique is proposed. The phased look loop (PLL) is used to track the natural frequency of the system. The small signal model of the system with the proposed control is obtained using extending describing function method (EDM). The validity of the proposed control is verified by simulation results.

Keywords: induction heating, AVC control, CDM, PLL, resonant inverter

Procedia PDF Downloads 664
1360 Backstepping Sliding Mode Control

Authors: Othmane Boughazi, Abdelmadjid Boumedienne, Hachemi Glaoui

Abstract:

This work treats the modeling and simulation of non-linear system behavior of an induction motor using backstepping sliding mode control. First, the direct field oriented control IM is derived. Then, a sliding for direct field oriented control is proposed to compensate the uncertainties, which occur in the control.Finally, the study of Backstepping sliding controls strategy of the induction motor drive. Our non linear system is simulated in MATLAB SIMULINK environment, the results obtained illustrate the efficiency of the proposed control with no overshoot, and the rising time is improved with good disturbances rejections comparing with the classical control law.

Keywords: induction motor, proportional-integral, sliding mode control, backstepping sliding mode control

Procedia PDF Downloads 487
1359 Deciding on Customary International Law: The ICJ's Approach Using Induction, Deduction, and Assertion

Authors: Maryam Nimehforush, Hamid Vahidkia

Abstract:

The International Court of Justice, as well as international law in general, may not excel in methodology. In contrast to how it interprets treaties, the Court rarely explains how it determines the existence, content, and scope of customary international law rules it uses. The Court's jurisprudence only mentions the inductive and deductive methods of law determination sporadically. Both the Court and legal literature have not extensively discussed their approach to determining customary international law. Surprisingly, the question of the Court's methodology has not garnered much attention despite the fact that interpreting and shaping the law have always been intertwined. This article seeks to redirect focus to the method used by the Court in deciding the customs of international law it enforces, emphasizing the importance of methodology in the evolution of customary international law. The text begins by giving explanations for the concepts of ‘induction’ and ‘deduction’ and explores how the Court utilizes them. It later examines when the Court employs inductive and deductive reasoning, the varied types and purposes of deduction, and the connection between the two approaches. The text questions the different concepts of inductive and deductive tradition and proves that the primary approach utilized by the Court is not induction or deduction but instead, assertion.

Keywords: ICJ, law, international, induction, deduction, assertion

Procedia PDF Downloads 9
1358 Modelling of Induction Motor Including Skew Effect Using MWFA for Performance Improvement

Authors: M. Harir, A. Bendiabdellah, A. Chaouch, N. Benouzza

Abstract:

This paper deals with the modelling and simulation of the squirrel cage induction motor by taking into account all space harmonic components, as well as the introduction of the bars skew, in the calculation of the linear evolution of the magnetomotive force (MMF) between the slots extremities. The model used is based on multiple coupled circuits and the modified winding function approach (MWFA). The effect of skewing is included in the calculation of motors inductances with an axial asymmetry in the rotor. The simulation results in both time and spectral domains show the effectiveness and merits of the model and the error that may be caused if the skew of the bars is neglected.

Keywords: modeling, MWFA, skew effect, squirrel cage induction motor, spectral domain

Procedia PDF Downloads 439
1357 Simulation Analysis and Control of the Temperature Field in an Induction Furnace Based on Various Parameters

Authors: Sohaibullah Zarghoon, Syed Yousaf, Cyril Belavy, Stanislav Duris, Samuel Emebu, Radek Matusu

Abstract:

Induction heating is extensively employed in industrial furnaces due to its swift response and high energy efficiency. Designing and optimising these furnaces necessitates the use of computer-aided simulations. This study aims to develop an accurate temperature field model for a rectangular steel billet in an induction furnace by leveraging various parameters in COMSOL Multiphysics software. The simulation analysis incorporated temperature dynamics, considering skin depth, temperature-dependent, and constant parameters of the steel billet. The resulting data-driven model was transformed into a state-space model using MATLAB's System Identification Toolbox for the purpose of designing a linear quadratic regulator (LQR). This controller was successfully implemented to regulate the core temperature of the billet from 1000°C to 1200°C, utilizing the distributed parameter system circuit.

Keywords: induction heating, LQR controller, skin depth, temperature field

Procedia PDF Downloads 41
1356 Exploring 'Attachment Theory' in the Context of Early Childhood Education

Authors: Wendy Lee

Abstract:

From the mid-twentieth century onward, the notion of ‘attachment’ has been used to define the optimum relationship between young children and their carers; first applied to parents and young children and more recently with early childhood educators and children in their care. However, it is seldom, if ever, asked whether the notion of ‘attachment’ and more especially so-called Attachment Theory, as propounded by John Bowlby and others, provides a sound basis for conceptualising child-adult relationships in early years. Even if appropriate in the context of family, the use of the term raises a number of questions when used in early childhood education. Research has shown that our youngest children (infants) in early childhood centre based care settings, are given the utmost priority to build 'attachments' with their educators. But exactly when, how and why does this priority diminish - and should it (for preschoolers)? This presentation will elaborate on such issues and will argue that there is a need to reconceptualise and redefine how 'quality relationships' should be measured and implemented in the daily practices and pedagogical methods adopted by early childhood educators. Moreover, this presentation will include data collected from the empirical study conducted, that observed various early childhood educators and children in Australian early childhood centres. Lastly, the thoughts, feelings and desires of parents of children in early childhood centre-based care, regarding the term 'attachment' and 'quality relationships' will be shared in the hope that we can take one step closer in bridging the needs of families, children, early childhood centres, educators, and the wider community.

Keywords: attachment, early childhood education, pedagogy, relationships

Procedia PDF Downloads 193
1355 Stator Short-Circuits Fault Diagnosis in Induction Motors Using Extended Park’s Vector Approach through the Discrete Wavelet Transform

Authors: K. Yahia, A. Ghoggal, A. Titaouine, S. E. Zouzou, F. Benchabane

Abstract:

This paper deals with the problem of stator faults diagnosis in induction motors. Using the discrete wavelet transform (DWT) for the current Park’s vector modulus (CPVM) analysis, the inter-turn short-circuit faults diagnosis can be achieved. This method is based on the decomposition of the CPVM signal, where wavelet approximation and detail coefficients of this signal have been extracted. The energy evaluation of a known bandwidth detail permits to define a fault severity factor (FSF). This method has been tested through the simulation of an induction motor using a mathematical model based on the winding-function approach. Simulation, as well as experimental, results show the effectiveness of the used method.

Keywords: Induction Motors (IMs), Inter-turn Short-Circuits Diagnosis, Discrete Wavelet Transform (DWT), Current Park’s Vector Modulus (CPVM)

Procedia PDF Downloads 563
1354 Integration of Technology for Enhanced Learning among Generation Y and Z Nursing Students

Authors: Tarandeep Kaur

Abstract:

Generation Y and Z nursing students have a much higher need for technology-based stimulation than previous generations, as they may find traditional methods of education boring and disinterested. These generations prefer experiential learning and the use of advanced technology for enhanced learning. Therefore, nursing educators must acquire knowledge to make better use of technology and technological tools for instruction. Millennials and generation are digital natives, optimistic, assertive, want engagement, instant feedback, and collaborative approach. The integration of technology and the efficacy of its use can be challenging for nursing educators. The SAMR (substitution, augmentation, modification, and redefinition) model designed and developed by Dr. Ruben Puentedura can help nursing educators to engage their students in different levels of technology integration for effective learning. Nursing educators should understand that technology use in the classroom must be purposeful. The influx of technology in nursing education is ever-changing; therefore, nursing educators have to constantly enhance and develop technical skills to keep up with the emerging technology in the schools as well as hospitals. In the Saskatchewan Collaborative Bachelor of Nursing (SCBSCN) program at Saskatchewan polytechnic, we use technology at various levels using the SAMR model in our program, including low and high-fidelity simulation labs. We are also exploring futuristic options of using virtual reality and gaming in our classrooms as an innovative way to motivate, increase critical thinking, create active learning, provide immediate feedback, improve student retention and create collaboration.

Keywords: generations, nursing, SAMR, technology

Procedia PDF Downloads 110
1353 Fourier Transform and Machine Learning Techniques for Fault Detection and Diagnosis of Induction Motors

Authors: Duc V. Nguyen

Abstract:

Induction motors are widely used in different industry areas and can experience various kinds of faults in stators and rotors. In general, fault detection and diagnosis techniques for induction motors can be supervised by measuring quantities such as noise, vibration, and temperature. The installation of mechanical sensors in order to assess the health conditions of a machine is typically only done for expensive or load-critical machines, where the high cost of a continuous monitoring system can be Justified. Nevertheless, induced current monitoring can be implemented inexpensively on machines with arbitrary sizes by using current transformers. In this regard, effective and low-cost fault detection techniques can be implemented, hence reducing the maintenance and downtime costs of motors. This work proposes a method for fault detection and diagnosis of induction motors, which combines classical fast Fourier transform and modern/advanced machine learning techniques. The proposed method is validated on real-world data and achieves a precision of 99.7% for fault detection and 100% for fault classification with minimal expert knowledge requirement. In addition, this approach allows users to be able to optimize/balance risks and maintenance costs to achieve the highest bene t based on their requirements. These are the key requirements of a robust prognostics and health management system.

Keywords: fault detection, FFT, induction motor, predictive maintenance

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