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Article
Publication date: 7 November 2016

Hannah Young

Intellectual disabilities (ID) may complicate the experience of bereavement and loss, in those with communicative impairments compounded by complex healthcare needs and…

Abstract

Purpose

Intellectual disabilities (ID) may complicate the experience of bereavement and loss, in those with communicative impairments compounded by complex healthcare needs and sensori-motor limitations. Whilst theorists have argued that the cognitive difficulties of people with profound ID impede mourning reactions, none have attempted to make sense of the responses they do exhibit. The current paper discusses this.

Design/methodology/approach

A select review considers the neurobiology underlying attachment bonds, complications in attachment formation and affect regulation in people with ID, and separation responses of people with profound ID.

Findings

The current paper demonstrates that by recognising the affective nature of separation distress, an understanding beyond a cognitive conceptualisation is possible.

Research limitations/implications

It is worth questioning whether people with profound ID are incapable of any meaningful form of person permanence. A critical review could deal with this comparatively by drawing on research of person and object permanence in typically developing children.

Practical implications

Of specific interest, the bio-behavioural regulators of relationships may help us to appreciate the importance of routine physical health and social care for emotional wellbeing in this group.

Originality/value

It is argued that by appreciating the basic emotional and regulatory functions of relationships, we can achieve a greater insight into the loss experiences of people with profound ID that will offer therapeutic direction.

Details

Advances in Mental Health and Intellectual Disabilities, vol. 10 no. 6
Type: Research Article
ISSN: 2044-1282

Keywords

Article
Publication date: 6 November 2017

Jingsong Li, Lixiang Wang, Qingxin Yang, Shanming Wang, Yongjian Li, Changgeng Zhang and Baojun Qu

Due to existence of skin effect under rotational excitation, especially to high-frequency motors and power transformers run at the frequency of hundreds or even thousands of…

Abstract

Purpose

Due to existence of skin effect under rotational excitation, especially to high-frequency motors and power transformers run at the frequency of hundreds or even thousands of hertz, core losses will increase significantly, which may cause local overheating damage, and the efficiency and longevity will be decreased. The purpose of this paper is to accurately calculate the rotational anomalous loss in electrical steel sheets.

Design/methodology/approach

The influence of skin effect to rotational anomalous loss coefficient is described in detail. Based on the rotational core losses calculation approach, the transformed coefficient and parameters of rotational anomalous loss are determined in accordance with experimental data obtained by using 3D magnetic properties testing system. Then, a variable loss coefficient calculation model of rotational anomalous loss is built. Meanwhile, a separation of the total 2D elliptical rotation experimental core losses is worked out.

Findings

The two methods are analysed and compared qualitatively. It should be noted that the novel calculation model can be more effectively presented anomalous loss features. Moreover, quantitative comparisons between 2D elliptical rotation and alternating core losses have achieved beneficial conclusions.

Originality/value

Transformed rotational anomalous loss coefficient and parameters of electrical steel sheets considering skin effect are determined. Based on that, a novel calculation model evaluating 2D elliptical rotation anomalous loss is presented and verified based on the experimental measurement and the separation of the total 2D elliptical rotation core losses. The 2D elliptical rotation core losses separation method and quantitative comparison with alternating excitation are helpful to engineering application.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 13 June 2019

Hanan Lu, Qiushi Li, Tianyu Pan and Ramesh Agarwal

For an axial-flow compressor rotor, the upstream inflow conditions will vary as the aircraft faces harsh flight conditions (such as taking off, landing or maneuvering) or the…

Abstract

Purpose

For an axial-flow compressor rotor, the upstream inflow conditions will vary as the aircraft faces harsh flight conditions (such as taking off, landing or maneuvering) or the whole compressor operates at off-design conditions. With the increase of upstream boundary layer thickness, the rotor blade tip will be loaded and the increased blade load will deteriorate the shock/boundary layer interaction and tip leakage flows, resulting in high aerodynamic losses in the tip region. The purpose of this paper is to achieve a better flow control for tip secondary flows and provide a probable design strategy for high-load compressors to tolerate complex upstream inflow conditions.

Design/methodology/approach

This paper presents an analysis and application of shroud wall optimization to a typical transonic axial-flow compressor rotor by considering the inlet boundary layer (IBL). The design variables are selected to shape the shroud wall profile at the tip region with the purpose of controlling the tip leakage loss and the shock/boundary layer interaction loss. The objectives are to improve the compressor efficiency at the inlet-boundary-layer condition while keeping its aerodynamic performance at the uniform condition.

Findings

After the optimization of shroud wall contour, aerodynamic benefits are achieved mainly on two aspects. On the one hand, the shroud wall optimization has reduced the intensity of the tip leakage flow and the interaction between the leakage and main flows, thereby decreasing the leakage loss. On the other hand, the optimized shroud design changes the shock structure and redistributes the shock intensity in the spanwise direction, especially weakening the shock near the tip. In this situation, the shock/boundary layer interaction and the associated flow separations and wakes are also eliminated. On the whole, at the inlet-boundary-layer condition, the compressor with optimized shroud design has achieved a 0.8 per cent improvement of peak efficiency over that with baseline shroud design without sacrificing the total pressure ratio. Moreover, the re-designed compressor also maintains the aerodynamic performance at the uniform condition. The results indicate that the shroud wall profile has significant influences on the rotor tip losses and could be properly designed to enhance the compressor aerodynamic performance against the negative impacts of the IBL.

Originality/value

The originality of this paper lies in developing a shroud wall contour optimization design strategy to control the tip leakage loss and the shock/boundary layer interaction loss in a transonic compressor rotor. The obtained results could be beneficial for transonic compressors to tolerate the complex upstream inflow conditions.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 11
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 December 2003

L. Dupré, M. De Wulf, D. Makaveev, V. Permiakov, A. Pulnikov and J. Melkebeek

This paper deals with the numerical modelling of electromagnetic losses in electrical machines, using electromagnetic field computations, combined with advanced material…

Abstract

This paper deals with the numerical modelling of electromagnetic losses in electrical machines, using electromagnetic field computations, combined with advanced material characterisations. The paper gradually proceeds to the actual reasons why the building factor, defined as the ratio of the measured iron losses in the machine and the losses obtained under standard conditions, exceeds the value of 1.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 22 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 May 2020

Reza Aghaei Togh and Mohammad Mahdi Karimi

This paper aims to present the designing and investigating various types of impulse blade profiles to find the optimal profile that has better performance than the first or…

Abstract

Purpose

This paper aims to present the designing and investigating various types of impulse blade profiles to find the optimal profile that has better performance than the first or original blade. The studied model is a turbine with an output power below 1 MW and a large pressure ratio up to 20, which is used to gain relatively high specific work output. As a result of its low mass flow rate, the turbine is used under partial-admission conditions. The turbine’s stator is a group of convergence–divergence nozzles that provide supersonic flow.

Design/methodology/approach

More than 10 types of two-dimensional blade profiles were designed using the developed preliminary design calculations and numerical analysis. The numerical results are validated using the existing experimental results. Finally, the case with improved performance is introduced as the final optimum case.

Findings

It was found that the performance parameters such as efficiency, power and torque are increased by more than 8% in the selected best model, in comparison with the original model. Moreover, the total pressure loss is 12% decreased for the selected model. Finally, the selected profile with superior performance is proposed.

Originality/value

Simultaneous numerical tests are conducted to examine the interaction of different supersonic blade profiles with the partially injected flow to the rotor.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 12 April 2022

Vittorio Di Vito, Giulia Torrano, Giovanni Cerasuolo and Michele Ferrucci

This paper aims to describe the advancements of the activities that have been carried out, in the Cost-Optimized Avionics SysTem (COAST) project, to complete the design and…

Abstract

Purpose

This paper aims to describe the advancements of the activities that have been carried out, in the Cost-Optimized Avionics SysTem (COAST) project, to complete the design and in-flight demonstration of the Tactical Separation System (TSS), which is an automatic support system to the pilot’s decision-making, onboard on small air transport (SAT) vehicles under single pilot operations, in the separation management.

Design/methodology/approach

In the framework of the Clean Sky 2 funded project COAST, some enabling technologies for single pilot operations in the EASA CS-23 category vehicles are designed and demonstrated in flight. Among the relevant flight management technologies addressed in the project, the specific one devoted to the real-time support to pilot’s decision-making in maintaining the vehicle self-separation is the TSS, designed by the Italian Aerospace Research Centre.

Findings

The TSS design started in the year 2016 and has been completed in the year 2021 after successful in-flight demonstration in the dedicated flight test campaign. The system has been validated by means of several simulation campaigns and finally demonstrated its effectiveness in providing its intended functionalities (situational awareness, conflict detection, conflict resolution) to the pilot in real flight trials, involving the presence of real conflicting aircraft.

Originality/value

The TSS contributes enabling the implementation of single pilot operations in CS-23 category vehicles, thanks to the possibility to support the pilot with provision of consolidated traffic picture, detection of conflicting surrounding traffic and suggestion of suitable conflict resolution manoeuvre real-time during the flight, through dedicated human–machine interface designed on purpose. The TSS supports the new separation modes that are envisaged in the future SESAR ATM target concept, with particular reference to the possible delegation of the separation responsibility to the pilot.

Book part
Publication date: 4 September 2017

Sara E. Green and Brianna Vice

The Social Model of Disability, which views social and economic barriers rather than individual bodily differences as the main sources of disadvantage faced by people living with…

Abstract

Purpose

The Social Model of Disability, which views social and economic barriers rather than individual bodily differences as the main sources of disadvantage faced by people living with impairments, has gained considerable traction in the literatures of both disability studies and the sociology of disability over the past several decades. Despite this success, however, concern has been expressed that there is a dearth of empirical evidence to back Social Model claims that people with disabilities are not emotionally distressed by their bodily differences or functional limitations, but rather by the layers of social and economic disadvantage imposed on top of their impairments.

Design/Methodology/Approach

Using results of a community survey in a small town in Florida, we examine the degree to which workforce participation and other social and economic disadvantages mediate the relationship between subjective well-being and the presence of functional impairments or self-described disability identity.

Findings

We find that study participants who report functional impairments or identify as disabled report lower levels of subjective well-being than participants who do not. Findings also suggest, however, that these differences in subjective well-being can be explained by lack of workforce participation and other aspects of social inclusion and economic disadvantages that are associated with functional impairment and disability identity. Results indicate that work is one, but not the only, important aspect of community participation that mediates between disability experience and well-being. Results also problematize the conflation of functional impairment and disability identity.

Implications

Findings point to a need for future qualitative and quantitative research to address differences between functional impairment status and disability identity and to evaluate the relative importance of work and other forms of social inclusion and access to economic recourses to the well-being of people living with impairments and disability.

Originality/value

Findings of this study provide empirical support for, but also add complexity to, the Social Model perspective. They can be used to provide guidance to community leaders in terms of ways in which the lives of residents with disabilities might be improved.

Details

Factors in Studying Employment for Persons with Disability
Type: Book
ISBN: 978-1-78714-606-8

Keywords

Article
Publication date: 13 July 2010

S. Jelassi, R. Romary and J.F. Brudny

The aim of this paper is to estimate the iron losses for an induction machine in the healthy case taking the slotting effect into account and to study the effect of an inter‐turn…

Abstract

Purpose

The aim of this paper is to estimate the iron losses for an induction machine in the healthy case taking the slotting effect into account and to study the effect of an inter‐turn short‐circuit on these losses. Theoretical results are then compared with experimental ones.

Design/methodology/approach

A simple analytical model of iron losses allows one to calculate and to appreciate the contribution of the slotting effect on induction machine iron losses without and with an inter‐turn stator short‐circuit. This semi‐analytical approach is based on the iron stator and rotor flux density repartition which is deduced from the air‐gap flux density.

Findings

The iron losses are not only due to the fundamental air‐gap flux density, but also to the slotting harmonics. In fact, the slotting effect generates harmonic flux density waves with very low magnitudes but with high‐angular velocities, leading to non‐negligible harmonic iron dynamic losses which have similar values on both the stator and the rotor. The inter‐turn short‐circuit generates an iron losses and a slotting harmonic contribution increase.

Research limitations/implications

Experimental measurements give the total iron losses. They do not allow separating the fundamental and the slotting harmonics contribution.

Practical implications

The knowledge of the iron losses behaviour in the healthy machine taking into account the slotting effect is important to optimize the design. The fault contribution on these losses allows one to estimate the damage which can be engendered by the fault.

Originality/value

Generally, iron losses studies and calculations are performed numerically using finite element software. The analytical approach can be interesting because it allows one to make faster calculations and to analyze the influence of the machine geometric parameters.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 20 April 2022

Qunfeng Zeng, Hao Jiang, Qi Liu, Gaokai Li and Zekun Ning

This paper aims to introduce a high-temperature grease design method assisted by back propagation neural network (BPNN) and verify its application value.

Abstract

Purpose

This paper aims to introduce a high-temperature grease design method assisted by back propagation neural network (BPNN) and verify its application value.

Design/methodology/approach

First, the grease data sets were built by sorting out the base data of greases in a large number of literatures and textbooks. Second, the BPNN model was built, trained and tested. Then, the optimized BPNN model was used to search the unknown data space and find the composition of greases with excellent high-temperature performance. Finally, a grease was prepared according to the selected composition predicted by the model and the high-temperature physicochemical performance, high-temperature stability and tribological properties under different friction conditions were investigated.

Findings

Through high temperature tribology experiments, thermal gravimetric analysis and differential scanning calorimetry experiments, it is proved that the high temperature grease prepared based on BPNN has good high-temperature performance.

Originality/value

To the best of the authors’ knowledge, a new method of designing and exploring high-temperature greases is successfully proposed, which is useful and important for the industrial applications.

Details

Industrial Lubrication and Tribology, vol. 74 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 27 January 2022

Martin Marco Nell, Marius Franck and Kay Hameyer

For the electromagnetic simulation of electrical machines, models with different ranges of values, levels of detail and accuracies are used. In this paper, numerical and two…

Abstract

Purpose

For the electromagnetic simulation of electrical machines, models with different ranges of values, levels of detail and accuracies are used. In this paper, numerical and two analytical models of an induction machine (IM) are analysed with respect to these aspects. The purpose of the paper is to use these analyses to discuss the suitability of the models for the simulation of various physical quantities of an IM.

Design/methodology/approach

An exemplary IM is simulated using the two-dimensional numerical finite element method, an analytical harmonic wave model (HWM) and an extended HWM. The simulation results are analyzed among themselves in terms of their level of detail and accuracy. Furthermore, the results of operating map simulations are compared with measured operating maps of the exemplary machine, and the accuracy of the simulation approaches is discussed in the context of measurement deviations and uncertainties.

Findings

The difference in the accuracy of the machine models depends on the physical quantity of interest. Therefore, the choice of the simulation method depends on the nature of the problem and the expected range of results. For modeling global machine quantities, such as mean torque or losses, analytical methods such as the HWM s are sufficient in many applications because the simulation results are within the range of measurement accuracy of current measurement systems. Analytical methods are also suitable for local flux density curves under certain conditions. However, for the simulation of the influence of local physical effects on the machine behavior and of temporally highly resolved quantities in saturated operating points, the accuracy of the analytical models decreases and the use of the finite element method becomes necessary.

Originality/value

In this paper, an extension of the HWM is used to calculate the IM, which, in contrast to the HWM, models the saturation. Furthermore, the simulation results of the different electromagnetic IM models are put into the context of the uncertainty of a measurement of several identical IMs.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

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