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The purpose of this study is to deals with the effect of premixed dual metal sulfides (tin disulfide + iron disulfide) as a replacement for antimony trisulfide on the tribological performance of brake friction materials.

In this study, brake friction materials were developed by using premixed dual metal sulfides as a replacement for antimony trisulfide in the formulation. The brake friction materials were developed in the form of standard brake pads as per the industrial practice. Thermal stability was measured for varying ingredients and developed brake pads using thermogravimetric analysis. The physical, mechanical and thermal properties of the developed brake pads were tested as per the industrial standards. The tribological properties were analyzed using the Chase test as per SAE J661. Worn surface analysis was done using a scanning electron microscope.

The experimental results indicate that the brake pads filled with premixed dual metal sulfides had good thermal stability, physical, chemical and mechanical properties with stable friction and less wear rate due to better lubrication preventing friction undulations.

This paper explains the influence of premixed dual metal sulfides as a replacement for antimony trisulfide in brake pads formulation to enhance the tribological performance by preventing friction undulations.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0144/

The purpose of this paper is performance enhancement of ferrite-assisted synchronous reluctance (FASR) motor using multi-objective differential evolution (MODE) algorithm, considering the significant geometric design parameters.

This work illustrates the optimization of FASR motor using MODE algorithm to enhance the performance of the motor considering barrier angular positions, magnet height, magnet axial length, flux barrier angles of the rotor and air gap length. In the optimization routine to determine the performance parameters, generalized regression neural network-based interpolation is used. The results of MODE are validated with multi-objective particle swarm optimization algorithm and multi-objective genetic algorithm.

The design optimization procedure developed in this work for FASR motor aims at achieving multiple objectives, namely, average torque, torque ripple and efficiency. With multiple objectives, it is essential to give the designer the tradeoff between different objectives so as to arrive at the best design suitable for the application. The results obtained in this work justify the application of the MODE approach for FASR motor to determine the various feasible solutions within the bounds of the design.

Analysis, design and optimization of synchronous reluctance motor has been explored in detail to establish its potential for variable speed applications. In recent years, the focus is toward the electromagnetic design of hybrid configurations such as FASR motor. It is in this preview this work aims to achieve optimal design of FASR motor using multi-objective optimization approach.

The results of this work will supplement and encourage the application of FASR motor as a viable alternate for variable speed drive applications. In addition, the application of MODE to arrive at better design solutions is demonstrated.

The approach presented in this work focuses on obtaining enhanced design of FASR motor considering average torque, torque ripple and efficiency as performance measures. The posteriori analysis of optimization provides an insight into the choice of parameters involved and their effects on the design of FASR motor. The efficacy of the optimization routine is justified in comparison with other multi-objective algorithms.

Industrial drives require appropriate control systems for reliable and efficient performance. With synchronous reluctance machines (SynRMs) slowly replacing the most commonly used induction, switched reluctance and permanent magnet machines, it is essential that the drive and its control be properly selected for enhanced performance. But the major drawback of synchronous reluctance motor is the presence of high torque ripple as its design is characterized by large number of variables. The solutions to reduce torque ripple include design modifications, choice of proper power electronic inverter and PWM strategy. But little has been explored about the power electronic inverters suited for synchronous reluctance motor drive to minimize torque ripple inherently by obtaining a more sinusoidal voltage. The purpose of this paper is to elaborate on the potential multilevel inverter topologies applicable to SynRM drives used in solar pumping applications.

The most significant field-oriented control using maximum torque per ampere algorithm for maximizing the torque production is used for the control of SynRM. Simulation results carried out using Matlab/Simulink are presented to justify the choice of inverter and its control technique for SynRM.

The five-level inverter drive gives lesser core or iron losses in the SynRMin comparison to the three- and two-level inverters due to lower Id current ripple. The five-level inverter reduces the torque ripple of the SynRM significantly in comparison to the three- and two-level inverter fed SynRM drives. The phase disposition-PWM control method used for the inverter shows the least total harmonic distortion (THD) levels in output voltage compared with the other level shifted PWM techniques.

Among the available topologies, a fitting topology is proposed for use for the SynRM drive to have minimal THD, minimal current and torque ripple. Additionally, this paper presents various modulation techniques available for the selected drive system and reports on a suitable technique based on minimal THD of output voltage and hence minimal torque ripple.

The purpose of this research is to automatically separate and extract meta‐data and instance information from various link pages in the web, by utilizing presentation and linkage regularities on the web.

Research objectives have been achieved through an information extraction system called semantic partitioner that automatically organizes the content in each web page into a hierarchical structure, and an algorithm that interprets and translates these hierarchical structures into logical statements by distinguishing and representing the meta‐data and their individual data instances.

Experimental results for the university domain with 12 computer science department web sites, comprising 361 individual faculty and course home pages indicate that the performance of the meta‐data and instance extraction averages 85, 88 percent F‐measure, respectively. Our METEOR system achieves this performance without any domain specific engineering requirement.

Important contributions of the METEOR system presented in this paper are: it performs extraction without the assumption that the object instance pages are template‐driven; it is domain independent and does not require any previously engineered domain ontology; and by interpreting the link pages, it can extract both meta‐data, such as concept and attribute names and their relationships, as well as their instances with high accuracy.

The purpose of this paper is to evaluate the perceptions of research priorities as expressed by people with spinal cord injury (SCI).

A descriptive study based on feedback from patients, rehabilitated following SCI was conducted in order to explore their felt needs for further research. A questionnaire was sent to 225 people who were rehabilitated following SCI. They were asked to indicate three priorities for further research on disability related issues. The questionnaire had a list of issues on different facets of disability following SCI. In total, 62 patients responded to the questionnaire.

Research on urinary incontinence was stated to have the highest priority among these different groups according to their age, marital status, duration of disability, and employment status. Rehabilitated patients of all age groups, irrespective of marital or employment status or duration of disability, indicated that further research is to be done on urinary incontinence.

A similar study among groups in a larger population would add further information.

Practitioners should address these expressed needs of the persons with SCI in the community.

These expressed needs will increase awareness among the team involved in the management of SCI in the community thus fill the gap between research and practice.

Research focussing on various problems associated with spinal cord injury have been carried out globally. On most of the occasions, the perceptions of the affected people regarding research areas are seldom obtained. This research would guide future directions of rehabilitation research in the field of spinal cord injury.

Work-based placements are central to the university education of allied health and social work (AHSW) students. As a result of COVID-19, the clinical learning environment of students' work-based placements was dramatically altered resulting in numerous documented challenges. This inter-disciplinary study aimed to evaluate AHSW students' perceptions and experiences of completing a diverse range of work-based placements during COVID-19.

This study was a mixed-method inter-disciplinary study using an anonymous online survey consisting of multiple choice, Likert scale and free text questions. Mixed-methods design supported amalgamation of insights from positivism and interpretivism perspectives and enabled research questions to be answered with both breadth and depth. 436 students were invited to participate who were enrolled in five AHSW educational university programmes: speech and language therapy, occupational therapy, physiotherapy, radiation therapy and social work. Data collected was analysed using both quantitative (descriptive and analytical statistics) and qualitative (thematic analysis) methods.

118 students participated (response rate: 27%) representing a range of AHSW disciplines who attended diverse placement settings. While there was extensive disruption in the learning environment leading to increased levels of stress and concern, a triad of individual and systemic supports helped to ensure positive work-based placement experiences and student success for the majority of AHSW students during COVID-19: (1) university preparation and communication; (2) placement site and supervisor support; and (3) students' resilience and capacity to adapt to a changed work-place environment.

This inter-disciplinary study reports the work-based placement experiences from the professional education programmes of healthcare students during the COVID-19 pandemic, giving a unique view of their perspectives and learning during this unprecedented crisis.

This paper aims to overcome some of the practical difficulties in assistive control of exoskeletons by developing a new assistive algorithm, called output feedback assistive control (OFAC) method. This method does not require feedbacks from force, electromyography (EMG) or acceleration signals or even their estimated values.

The presented controller uses feedbacks from position and velocity of the output link of series elastic actuators (SEAs) to increase the apparent integral admittance of the assisted systems. Optimal controller coefficients are obtained by maximizing the assistance ratio subjected to constraints of stability, coupled stability and a newly defined comfort measure.

The results confirm the effectiveness of using the inherent properties of SEAs for removing the need for extra controversial sensors in assistive control of 1 degree of freedom (1-DOF) SEA powered exoskeletons. The results also clearly indicate the successful performance of the OFAC method in reducing the external forces required for moving the assisted systems.

As the provided experiments indicate, the proposed method can be easily applied to single DOF compliantly actuated exoskeletons to provide a more reliable assistance with lower costs. This is achieved by removing the need for extra controversial sensors.

This paper proposes a novel assistive controller for SEA-powered exoskeletons with a simple model-free structure and independent of any information about interaction forces and future paths of the system. It also removes the requirement for the extra sensors and transforms the assistive control of the compliantly actuated systems into a simpler problem of position control of the SEA motor.

The purpose of this paper is to deal with the tribological study on the brake pads developed using various purity-based graphitized graphite.

This paper deals with developing copper-free brake pads by using graphite as a key lubricant produced using a graphitization process with purity percentages (85, 90 and 95%). The brake pads were developed using traditional manufacturing processes and evaluated for their physical, chemical, thermal and mechanical properties as per industrial standards. Fade and recovery characteristics were analyzed using a full-scale inertia brake dynamometer as per JASO-C-406. The scanning electron microscope was used to analyze the worn surfaces of the brake pads.

The testing findings reveal that the brake pads with 95% graphitized graphite showed better shear strength with good adhesion levels and lesser density, hardness, acetone extract value, loss on ignition and higher porosity. Effectiveness studies of brake pads with graphite (95% graphitized) showed better results at higher pressure speed conditions than others because of better plateau formation and adequate lubrication.

This paper discusses graphitized graphite of different purity influences brake pad's tribological performance by modifying tribo-films and reducing friction undulations.

This chapter situates the South Pacific region’s engagement in progressing gender equality and women’s empowerment within broader gender and development (GAD) debates. It explores the international ‘gender agenda’ and how its associated frameworks, platforms, policies and metrics have diffused throughout the South Pacific. Limited progress in achieving gender equality and empowerment goals has been made, globally and regionally, with considerable challenges yet to be overcome. Complementing the book’s focus on the integration of gender into agricultural research and development projects, the chapter reviews rural women’s access to income and land in the South Pacific, and their contributions to agricultural production and marketing.

The purpose of this paper is to review different microfinance products and services that can be offered to reduce the financial vulnerabilities of communities at risk. Following a detail literature review, the effectiveness of different forms of microfinance services in creating resilience in the affected communities was analysed and whether they can be applied to mitigate the risk of future disasters was assessed. In addition, the study was conducted to assess whether microcredit can help reduce direct risk exposure of the poor through income smoothing.

This study is based on a review of existing theories.

The notion that most vulnerable communities are financially weak is evident from studies. This study finds that microcredit can help reduce direct risk exposure of poor through income smoothing, while saving can help them recover from the losses of disasters. Our review also suggests that there is no specific model of microfinance services which can have a holistic impact on the financial capacity-building, particularly during the rehabilitation process.

There are different categories of microfinance products with distinct characteristics and associated benefits to the communities. Some of the major microfinance products as identified in this study are, saving products, credit products and insurance products. These products have multidimensional benefits, as there are many approaches adopted by microfinance institutions (MFIs) and clients regarding the use of these products. However this study focuses on the use of these products towards resilience development in the community. Other applications of these products still need to be explored.

There is a need for a comprehensive financial tool that can be effectively applied to expedite the process of rehabilitation and reduce the financial impact of disasters on the community, particularly the poor. Major issues in the context of disasters faced by MFIs to design their products in the affected areas are also highlighted in the study.

The study throws lights on different microfinancial tools such as microloans, microcredits and cash for work, etc. offered by banks and other organizations and highlights their role in the rehabilitation and reconstruction of those affected by disasters in different parts of the world.

This paper contributes to the discourse of microfinance and its social applications in developing countries. It provides original role of microfinance as a tool for creating community resilience to the impacts of disasters.