Search results for "induction"
showing 10 items of 769 documents
Residents'corner April 2014. Editorial: what's new this month?
2014
In this issue of the European Journal of Dermatology, Bircher et al.[1] revisit tolerance induction in drug hypersensitivity reactions, which is a controversial issue, particularly in delayed hypersensitivity reactions. Drug hypersensitivity may present as a mild, moderate or severe life-threatening reaction, becoming a problem for many patients when the offending drug is essential (and even irreplaceable).Determining which drug is responsible for the reaction may be challenging, especially in multiple [...]
Therapeutic drug monitoring for antidepressant drug treatment.
2012
The aim of antidepressant drug treatment is to produce remission without causing adverse effects during the acute phase of the illness and to prevent relapses or recurrences during continuation or maintenance therapy. To achieve these goals, drug choice and dosage must be optimized for each patient individually. Therapeutic drug monitoring (TDM), which is based on the assumption that clinical effects correlate better with blood levels than doses, can be helpful. When using tricyclic antidepressant drugs TDM enhances safety and efficacy. For newer antidepressant drugs, however, it is a matter of debate to which extend TDM can have beneficial effects. For many antidepressants there exist care…
Dose adjustments and discontinuation in TNF inhibitors treated patients: when and how. A systematic review of literature.
2018
Objectives To review the available evidence concerning the possibility of discontinuing and/or tapering the dosage of TNF inhibitors (TNFi) in RA patients experiencing clinical remission or low disease activity. Methods A systematic review of the literature concerning the low dosage and discontinuation of TNFi in disease-controlled RA patients was performed by evaluation of reports published in indexed international journals (Medline via PubMed, EMBASE), in the time frame from 8 April 2013 to 15 January 2016. Results We analysed the literature evaluating the efficacy and the safety of two different strategies using TNFi, decreasing dosage or discontinuation, in patients experiencing clinica…
Input-Output Feedback Linearization Control of a Linear Induction Motor Taking Into Consideration Its Dynamic End-Effects and Iron Losses
2020
This article proposes a new input-output feedback linearization control (FLC) technique of linear induction motors (LIMs), taking into consideration both the dynamic end-effects and the iron losses. Starting from a previously conceived dynamic model, including the dynamic end-effects and the iron losses, all the theoretical framework of the FLC has been developed. The proposed FLC improves a previous version of FLC in accounting also the iron losses, which in LIMs with fixed-secondary sheet play a pivotal role more than in rotating induction motors (RIMs). The proposed FLC has been experimentally tested on a suitably developed test setup, and experimental comparisons between the proposed FL…
Peer-group mentoring as a tool for teacher development
2014
Abstract: Peer-group mentoring (PGM) is a new model designed to support the professional development of teachers in Finland. This study examines the experiences of mentees participating in PGM and potential differences in the experiences of teachers in general education and vocational education. It also addresses the mentees perceptions of the results of PGM with regard to the professional, personal and social dimensions of professional development. Quantitative research methods were used. An online survey was completed by 69 teachers in general education and 47 teachers in vocational education (n = 116). The results showed that the participants saw PGM as an important tool for professional…
EKF-based estimation and control of electric drivetrain in offshore pipe racking machine
2016
A typical challenge for electric drivetrains is to reduce the number of sensors required for control action or system monitoring. This is particularly important for electric motors operating in offshore conditions, since they work in hostile environment which often damages data acquisition systems. Therefore, this paper deals with verification and validation of the extended Kalman filter (EKF) for sensorless indirect field-oriented control (IFOC) of an induction motor operating in offshore conditions. The EKF is employed to identify the speed of the induction motor based on the measured stator currents and voltages. The estimated speed is used in the motor speed control mode instead of a ph…
Fault Diagnostics for Electrically Operated Pitch Systems in Offshore Wind Turbines
2016
This paper investigates the electrically operated pitch systems of offshore wind turbines for online condition monitoring and health assessment. The current signature based fault diagnostics is developed for electrically operated pitch systems using model-based approach. The electrical motor faults are firstly modelled based on modified winding function theory and then, current signature analysis is performed to detect the faults. Further, in order to verify the fault diagnostics capabilities in realistic conditions, the operating profiles are obtained from FAST simulation of offshore wind turbines in various wind conditions. In this way, the applicability of current signature analysis for …
Bearing fault diagnosis for inverter-fed motors via resonant filters
2014
Current-based technique is an economic solution to detect bearing faults in drive-trains. Localized faults produce characteristic vibration frequencies. When an electric motor is supplied by a frequency-converter, the current response includes not only the fundamental and fault related frequencies but also higher harmonics from the inverter. This paper introduces a resonant filter to pick up frequency components caused by the localized faults. The bearing fault frequencies are calculated by bearing geometry and motor speeds. The filter frequencies are selected as a function of motor speeds. The filter is independent of the load condition, so it can work at different motor operating points t…
Experimental comparison between direct and indirect measurement techniques for the characterization of Linear Induction Motors
1997
Abstract An experimental comparison between direct and indirect measurement techniques for the on-line characterization of Linear Induction Motors (LIMs) is presented. Indirect measurements are based on a mathematical model of the motors. Direct measurements are carried out by means of traditional instruments and a smart sensor, located on the LIM and linked to the controller by the power supply line. Both a synthetic description of the LIM model and the sensor architecture are reported. The experimental results, achieved by applying different feeding strategy, are discussed.
A Contribution to Tests Standardization for Inverter-Fed Asynchronous Machines
1986
Losses of inverter-fed asynchronous motors and their experimental evaluation are considered. The formal expressions of iron and copper losses are first recalled, and it is shown as they are influenced by the harmonic content of inverter output voltages. Theoretical and experimental values of these losses are then given together with the presentation of the experimental tests used for their determination. A suitable set of tests is then suggested for the determination of the conventional efficiency of inverter-fed asynchronous motors. The content cannot be considered exhaustive on the matter. It represents only a first contributive approach to the standardization of inverter-fed asynchronous…