Saravanan Sivasamy, M. Marsaline Beno Maria and Prabhu Sundaramoorthy
The automotive industry extensively uses switched reluctance motors (SRM) because of their excellent performance. The main purpose of this article is to investigate the design of…
Abstract
Purpose
The automotive industry extensively uses switched reluctance motors (SRM) because of their excellent performance. The main purpose of this article is to investigate the design of a particular type of SRM called doubly salient outer rotor switched reluctance motor (DSORSRM) for electric vehicle application in this paper.
Design/methodology/approach
Different configurations of DSORSRM motor such as long flux path SRM, reduced flux path mutually coupled SRM and short flux path SRM (SF-SRM) are considered for investigation. The best configuration based on average torque is selected for further investigation by conducting an electromagnetic analysis. Also, in the proposed design, laminating material with low iron loss and superior performance characteristics is selected by doing electromagnetic analysis for SRM with M19, M660-50D, M-19 and M800-100A non-oriented laminating core material. Because vibrations are produced in DSORSRM devices as a result of changing induction, a mechanical analysis was performed to estimate the natural frequencies of vibration and the amplitudes that may lead to acoustic noises.
Findings
SF-SRM configuration with three-phase, 12/10, 250 W, 48 V, 1,000 rpm is selected with the impact in the elimination of flux reversals and also has various salient features such as singly excited, no rotor windings, no permanent magnet, pure in construction and high starting torque. Still, this SRM suffers from vibration owing to changing induction. In lamination material selection, M19 is chosen as optimized material to obtain vibration reduction. Vibration analysis was performed for the optimized 12/10 SF-SRM with M19 lamination material, and the corresponding modes for the machine to operate with reduced vibration are analyzed. The current and speed characteristics of the prototype model for the DSORSRM motor are obtained and validated with finite element analysis (FEA) results.
Originality/value
The performed FEA result shows that the proposed DSORSRM with short flux path configuration produces a high average torque of 1.915 N m. The M19 lamination material gives a minimum iron loss of 9.056 W. The modal frequencies are estimated and validated with numerical equations.
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Prabhu Sundaramoorthy, Balaji M., Suresh K., Ezhilventhan Natesan and Mohan K.
The main purpose of this research is to investigate finite-element analysis (FEA) on flux reversal-free stator switched reluctance motor (FRFSSRM) for industrial applications. The…
Abstract
Purpose
The main purpose of this research is to investigate finite-element analysis (FEA) on flux reversal-free stator switched reluctance motor (FRFSSRM) for industrial applications. The vibration analysis for an electrical machine is essential because of the acoustic noises. The acoustic noises originate by coincidence of natural frequencies of motor with the vibration frequencies.
Design/methodology/approach
The identification with the performance for FRFSRM by torque ripple, vibration. The vibration of the machine is because of unbalanced electromagnetic forces. The mutual coupled winding and a common pole between two adjacent exciting poles reduce these unbalanced forces.
Findings
The accelerometer is used to monitor the vibration amplitude in transient mode. A comparison study shows that the vibration is less in the E-core SRM than in the conventional flux reversal SRM.
Originality/value
The shorter flux path reduces the torque ripple and vibration content in SRM. This research article mainly focuses on the parameters such as vibration and torque ripple. The vibration of FRFSRM is identified by accelerometer; ANSYS Package predicts the simulation of the vibration measurement. The dynamic behaviors of this E-core SRM model with rated conditions the vibration had predicted.
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G. Prabhu, Vijyendra Pandey, Sundaramoorthy Jeyavel and Rajgopal Greeshma
Unfortunately, workplace incivility (WI) within the information technology (IT) sector has hardly been covered in extant literature. Therefore, through narratives, this study…
Abstract
Purpose
Unfortunately, workplace incivility (WI) within the information technology (IT) sector has hardly been covered in extant literature. Therefore, through narratives, this study explored various situational and cultural attributes of WI in the Indian IT sector.
Design/methodology/approach
Semi-structured interviews were conducted among the IT professionals (N = 24; Males = 13, Females = 11) aged between 21 and 45 years (Mean = 31.20, SD = 6.56) working in the South Indian state of Karnataka (Bengaluru).
Findings
The narrative thematic analysis yielded the following themes: Experiences of managers' ill-treatment at the workplace, co-workers incivility: dominance in the IT sector and prevalence of gender-based interpersonal discrimination. Furthermore, many sub-themes emerged under each major theme.
Research limitations/implications
Contexts and cultural attributes of WI experiences warrant reconsidering and redefining the concept's theoretical underpinnings, especially from multi-cultural contexts, i.e. India, unlike leading studies in the Western culture. Current study narratives would guide further explorations of how IT professionals wish to curtail these behaviours and suggest strategies to minimize these behaviours in the respective sector.
Originality/value
The findings pose an interesting question for further investigation such as: Do individuals who seek favours from co-workers, under certain conditions, invite the experiences of WI for themselves from potential favour-doer? In a first of its kind, the study also offered relevant insights into exploring whether intentional acts as uncivil behaviours are peculiar to multi-cultural contexts, such as in India.
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Daniela Fishbein, Siddhartha Nambiar, Kendall McKenzie, Maria Mayorga, Kristen Miller, Kevin Tran, Laura Schubel, Joseph Agor, Tracy Kim and Muge Capan
Workload is a critical concept in the evaluation of performance and quality in healthcare systems, but its definition relies on the perspective (e.g. individual clinician-level vs…
Abstract
Purpose
Workload is a critical concept in the evaluation of performance and quality in healthcare systems, but its definition relies on the perspective (e.g. individual clinician-level vs unit-level workload) and type of available metrics (e.g. objective vs subjective measures). The purpose of this paper is to provide an overview of objective measures of workload associated with direct care delivery in tertiary healthcare settings, with a focus on measures that can be obtained from electronic records to inform operationalization of workload measurement.
Design/methodology/approach
Relevant papers published between January 2008 and July 2018 were identified through a search in Pubmed and Compendex databases using the Sample, Phenomenon of Interest, Design, Evaluation, Research Type framework. Identified measures were classified into four levels of workload: task, patient, clinician and unit.
Findings
Of 30 papers reviewed, 9 used task-level metrics, 14 used patient-level metrics, 7 used clinician-level metrics and 20 used unit-level metrics. Key objective measures of workload include: patient turnover (n=9), volume of patients (n=6), acuity (n=6), nurse-to-patient ratios (n=5) and direct care time (n=5). Several methods for operationalization of these metrics into measurement tools were identified.
Originality/value
This review highlights the key objective workload measures available in electronic records that can be utilized to develop an operational approach for quantifying workload. Insights gained from this review can inform the design of processes to track workload and mitigate the effects of increased workload on patient outcomes and clinician performance.