Transient voltage distribution in stator winding of electrical machine fed from a frequency converter

Standard induction motors are exposed to steep-fronted, non-sinusoidal voltages when fed from frequency converters. These wave patterns can be destructive to the insulation. The aim of the present work is to develop methods of predicting the magnitude and distribution of fast voltage within the stator winding of an electric machine fed from a frequency converter. Three methods of predicting the magnitude and distribution of fast voltages within form windings commonly used in medium and high voltage machines are described. These methods utilise some aspects of previously published works on the surge propagation studies to achieve simplification of the solution without loss of accuracy. Two of these methods are applied to the voltage calculation in random winding commonly used in low voltage machines. Multi-conductor transmission line theory forms the basis of the methods described in this work. Computation of the voltage distribution using either of these methods requires the calculation of the parameters for the slot and the end (over-hang) part of the winding. The parallel plate capacitor method, the indirect boundary integral equation method and the finite element method are the three possible methods of calculating the capacitance also described in this work. Duality existing between the magnetic and the electric field has been used for the inductance calculation. Application of these methods to the voltage calculation in the first coil from the line-end of a 6 kV induction motor is shown to be successful. From the computed and measured voltage results it is evident that the improved accuracy for the capacitance values is sufficient to give good agreement between the measured and calculated inter-turn voltages without the need to infer the presence of a surface impedance effect due to the laminated core. Application of two of these methods for the transient voltage calculation on the first coil from the terminal-end of low voltage induction motors with random windings is also shown to be successful. Comparison between the computed and the measured results shows that the turn-to-ground capacitance matrix obtained in over-hang part of the coil can be assumed the for the slot part of the coil. With this assumption modelling the first five turns in the line-end coil produce turn and coil voltage that match well with the corresponding measuring result. The methods of voltage computation described in this work should be of great help to engineers and researchers concerned with the turn strength and over-voltage protection in high and low voltage motors.reviewe

Causes of Delays during Housing Adaptation for Healthy Aging in the UK

Housing adaptation is a rehabilitation intervention that removes environmental barriers to help older people accommodate changing needs and age in place. In the UK, funding application for home adaptations to local authorities is subject to several procedural steps, including referral, allocation, assessment, funding and installation. The five stages need to complete in a sequential manner, often cause long delays

Evaluation of the Efficacy of African Basil (Ocimum gratissimum) Leaf for Disinfecting Well - water obtained from Ekiti State, Nigeria

The demand for potable and affordable water led to comparative research of the efficacy of Ocimum gratissimum Leaf (OGL) extract by collecting well water and treated with OGL extract. Both treated and untreated samples were subjected to physiochemical and bacteriological examinations. Data obtained showed that the pH and feacal coliform counts ranged from 6.17 to 6.74 and 0 to 192 CFU/100 mL for well water sample A; 6.56 to 7.24 and 0 to 118 CFU/100 mL for well water samples B; 6.81 to 7.79 and 0 to 75 CFU/100 mL for well water samples C respectively. The OGL extract includes various bioactive components (i.e. steroids, tannins, etc) according to the phytochemical tests. The first feacal coliform count was above the allowed range (i.e. >50 CFU/100 mL) and the pH value tended to be acidic (6.5), with a colour of >15 H.U. and an unclear (brownish) appearance. The Coliform count was lowered with each dosage of OGL extract until it reached zero count after 24 hours’ contact time at an optimum dosage of 5 mL and the total bacteria counts were gone. The beneficial influence (s) from this study confirms the disinfectant potential of OGL extract for well water treatment

Smart housing adaptations register with user matching functionalities for different mobility categories for the social housing sector

Purpose The lack of a proper register to store, match and display information on the adapted property has led to a waste of resources and prolonged delays in matching the disabled and elderly people with appropriate properties. This paper presents the development of a Housing Adaptations Register with user-matching functionalities for different mobility categories. The developed system accurately captures and documents adapted home information to facilitate the automated matching of disabled/aged applicants needing an adapted home with suitable property using banding, mobility and suitability index. Design/methodology/approach A theoretical review was conducted to identify parameters and develop adaptations register construct. A survey questionnaire approach to rate the 111 parameters in the register as either moderate, desirable or essential before system development and application. The system development relied on DSS modelling to support data-driven decision-making based on the decision table method to represent property information for implementing the decision process. The system is validated through a workshop, four brainstorming sessions and three focus group exercises. Findings Development of a choice-based system that enables the housing officers or the Housing Adaptations Register coordinators to know the level of adaptation to properties and match properties quickly with the applicants based on their mobility status. The merits of the automated system include the development of a register to capture in real-time adapted home information to facilitate the automated matching of disabled/aged applicants. A “choice-based” system that can map and suggest a property that can easily be adapted and upgraded from one mobility band to the other. Practical implications The development of a housing adaptation register helps social housing landlords to have a real-time register to match, map and upgrade properties for the most vulnerable people in our society. It saves time and money for the housing associations and the local authorities through stable tenancy for adapted homes. Potentially, it will promote the independence of aged and disabled people and can reduce their dependence on social and healthcare services. Originality/value This system provides the local authorities with objective and practical tools that may be used to assess, score, prioritise and select qualified people for appropriate accommodation based on their needs and mobility status. It will provide a record of properties adapted with their features and ensure that matching and eligibility decisions are consistent and uniform

Development of a smart home suitability indicator and indicative self-assessment platform for the disabled facilities grants (DFGs)

Purpose: Delay in housing adaptation is a major problem, especially in assessing if homes are suitable for the occupants and in determining if the occupants are qualified for the Disabled Facilities Grant (DFG). This paper describes the development of two self-administered intelligent integrated assessment tools from the DFG Adapt-ABLE system: (1) The Home Suitability Assessment Platform, which is a preventive mechanism that allows assessment of the suitability of homes based on occupants’ mobility status and (2) an indicative assessment platform that determines if the applicants are qualified for the DFG to prevent lengthy delays. Design/methodology/approach: The adopted method aligned with a development study approach: a grounded literature review, a severity measurement approach, two stakeholder engagement workshops, four brainstorming sessions and four focus group exercises. The system development relied on Entity–Relationship Diagram (ERD) technique for data structures and database systems design. It uses DFG context sensitivity with alignment with DFG guidance, interlinkages and interoperability between the assessment tools and other platforms of the integrated Adapt-ABLE system. Findings: The assessment tools are client-level outcomes related to accessibility, usability and activity based on the assessment process. The home suitability platform shows the percentage of the suitability of a home with assessment results that suggest appropriate action plans based on individual mobility status. The indicative assessment combines the function of referral, allocation, assessment and test of resources into an integrated platform. This enables timely assessment, decision-making and case-escalation by Occupational Therapists based on needs criteria and the eligibility threshold. Originality/value: These assessment tools are useful for understanding occupants’ perception of their physical housing environment in terms of accessibility, suitability and usability based on basic activities of daily living and their mobility status. The indicative self-assessment tool will substantially cut down the application journey. The developed tools have been recommended for use in the CSJ Disability Commission report and the UK government Guidance on DFGs for local authorities in England

Development of Adapt-ABLE smart system – an end-to-end system for speeding up disabled housing adaptation process

Purpose The problem of long delay and waiting time in Disabled Facilities Grants (DFG) housing adaptation has been ongoing for years. This study aimed at constructing an innovative smart solution to streamline the housing adaptation process to prevent lengthy delays for disabled and elderly people. Design/methodology/approach The Adapt-ABLE approach is suggested based on a constructive research approach, where extensive theoretical development of the Adapt-ABLE concept is developed. It consists of four integrated platforms that undergo theoretical and analogical development and validations through applicable theories, a workshop, four brainstorming sessions and a focus group. Findings The proposed Adapt-ABLE approach utilises process optimisation techniques through an IT system for streamlining the process. The merits of the semi-automated system include the development of a preventive measure that allows measurement of suitability index of homes for the occupants, indicative assessment that shorten the application duration, procurement and contracting platform that utilises principles based on framework agreement and call-off contract, and a platform that standardised performance management for continuous improvement. Originality/value The Adapt-ABLE solution will cut the application journey of non-qualified applicants and suggest where help can be sought. The qualified applicants' application journey will also be shortened through an online indicative assessment regime and early online resources (means) testing. Overall, the proposed system reduces the waiting time, and timely delivery improves the applicant's quality of life by living independently. It will potentially save the NHS billions of pounds used to replace hips and residential care costs due to lengthy delays in the housing adaptations process

A Cloud-based Collaborative Ecosystem for the Automation of BIM Execution Plan (BEP)

Master Information Delivery Plan (MIDP) is a key requirement for BIM Execution Plan (BEP) that enlists all information deliverables in BIM-based project, containing information about what would be prepared, when, by who, as well as the procedures and protocols to be used. In a well-conceived BEP, the MIDP facilitates collaboration among stakeholders. However, current approaches to generating MIDP are manual, making it tedious, error-prone, and inconsistent, thereby limiting some expected benefits of BIM implementation. The purpose of the present research is to automate the MIDP and demonstrate a collaborative BIM system that overcomes the problems associated with the traditional approach. A BIM cloud-based system (named Auto-BIMApp) involving naming that automated MIDP generation is presented. A participatory action research methodology involving academia and industry stakeholders is followed to design and validate the Auto-BIMApp. A mixed-method experiment is conducted to compare the proposed automated generation of MIDP using Auto-BIMApp with the traditional practice of using spreadsheets. The quantitative results show over 500% increased work efficiency, with improved and error-free collaboration among team members through Auto-BIMApp. Moreover, the responses from the participants using Auto-BIMApp during the experiment shows positive feedback in term of ease of use and automated functionalities of the Auto-BIMApp. The replacement of traditional practices to a complete automated collaborative system for the generation of MIDP, with substantial productivity improvement, brings novelty to the present research. The Auto-BIMApp involve multidimensional information, multiple platforms, multiple types, and levels of users, and generates three different representations of MIDP

Challenges and benefits of LED retrofit projects: a case of SALIX financed secondary school in the UK

The recent surge in light emitting diode (LED) lighting retrofitted into schools in the UK is as a result of the UK Government’s 2050 zero carbon pledge. However, the benefits and consequences of LED retrofit projects for staff and enablers and stakeholder knowledge gaps about LED lighting retrofitting have not been fully explored. The aim of this research is to determine the amount of savings in cost, carbon reduction and kilowatt usage and to confirm if repayment from energy and cost savings derived from LED retrofit school projects funded through the SALIX funding option in the UK would be enough to service the loan. Thus, it examines monetary and non-monetary benefits, internal project stakeholder knowledge gaps and the consequences of LED retrofit for the staff and enablers of a large community college in the UK which is funded through the SALIX funding option. Design/methodology/approach: The methodology relied on a hybrid research approach of a case secondary school through the review of literature, analysis of secondary data, focus group and questionnaire survey. The focus group consists of six key project stakeholders. The secondary data was sourced from the Project IGP [Individual Grade Proposal] and the Positive Energy Report from Zenergi, and the closed online questionnaire survey was used to sample 150 teaching staff and school enablers. Findings: The findings show that stakeholders lack project knowledge, trust and expertise/project comprehension. This is in terms of baseline information, LED technology/management, payback modalities, management of risks and ethical issues around environmental impact. The forecasted SALIX savings were not achieved in real-time, partly because it does not take into consideration the increase in energy costs over the payback period. However, the LED retrofit creates efficiencies; drives down energy costs and energy usage; and drives carbon reduction, helping pupils’ learning, improving productivity and performance, and finally leading to a better lighting environment for the school community. Originality/value: The study will help schools in the UK that intend to access SALIX finance for LED retrofits to understand the challenges and mitigate the risks. It will also help the government to understand the importance of adjusting the payback modalities to the base price when the retrofit was carried out for real-time savings to be made. The research would be useful in ensuring the proactive involvement of all the identified stakeholders in understanding the challenges and what the function entails

The disruptive factors and longevity effects of Covid-19 and Brexit on the SMEs construction supply chain in the UK

Purpose Supply chain disruptions have a significant impact on overall project delivery. This study aims to identify the supply chain disruptive factors and develop a framework to mitigate the disruptive effects on the supply chain. Covid-19 and Brexit disruption and their longevity effects in the short, medium and long term on the supply chain are relied upon to develop the framework. Design/methodology/approach The study adopted a mixed-method approach with a sequential explanatory design. The main disruptive factors were identified through a literature review, and key factors were selected through a focus group exercise. A questionnaire survey was carried out to sample opinions from the practitioners; 41 questionnaires were received and analysed using the relative importance index (RII) method for ranking the factors and percentage frequency distribution to determine the longevity effects. Five follow-up semi-structured interviews were conducted over the telephone and later transcribed. Findings The results of Covid-19 disruption indicate that material cost increase ranked first (RII: 0.863), logistics cost increase and supply chain interaction ranked second and third, respectively. They have long-term, medium-term and short-term longevity effects, respectively. The lowest-rated factors were communication (RII: 0.561), staff shortages (RII: 0.629) and impact on relationships (RII: 0.639). The three most ranked Brexit disruptive factors are supply chain interaction (RII: 0.775), material cost increase (RII: 0.766) and logistic and haulage delay (RII: 0.717). The first two factors have long-term effects, and the logistics and haulage delays have a medium-term impact. The mitigating solutions suggested in the framework are collaborative working, stronger resilience to external forces and better transparency and communication that will lead to good relationships among the supply chain members. Researchlimitations/implications The scope of the study was limited to the UK construction industry; however, the pandemic effect on supply chain can serve as critical learning curve in other developed and developing countries. Practical implications The study will help the government and construction firms to understand the focal areas of importance in solving the supply chain disruption problems based on the effects of Brexit and Covid-19. The research would be useful in ensuring the proactive involvement of the government and contracting firms in their preparedness for similar events in the future. The results could be interpreted for critical learning in other developed/developing countries. Originality/value Identifying and ranking the supply chain disruptive factors affecting the small‐ and medium‐sized enterprises (SMEs) in the UK construction industry has been the focal point of this study. The study also proposes a simple but effective framework comprising the highly ranked factors, their longevity effects and mitigating measures. This will help the SMEs manage future/similar external events affecting the supply chain