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Article
Publication date: 5 August 2019

Olubayo Moses Babatunde, Josiah Lange Munda and Yskandar Hamam

The application of hybrid renewable energy system (HRES) can mitigate inadequate access to clean, stable and sustainable energy among households in sub-Saharan Africa (SSA)…

297

Abstract

Purpose

The application of hybrid renewable energy system (HRES) can mitigate inadequate access to clean, stable and sustainable energy among households in sub-Saharan Africa (SSA). Available studies on HRES seem to concentrate only on its techno-economic and environmental viability. In so doing, these studies do not seem to underline the likely challenges that follow the acquisition of HRES by especially low-income households. The ensuing reality is, of course, a limitation in the use of HRES in homes with low incomes. It is therefore imperative to analyze how a household with low income can afford this kind of energy system. The purpose of this study, therefore, lies in presenting a techno-economic, environmental and affordability analysis of how HRES is acquired.

Design/methodology/approach

To arrive at a grounded analysis, a typical household in SSA is used as an example. The analysis focused on the pattern of energy use, and this is obtained by visiting an active site to evaluate the comprehensive load profile. In the course of analysis, an optimal techno-economic design and sizing of a hybrid PV, wind and battery were undertaken. Additionally, an acquisition analysis was done based on loan amortization.

Findings

The interesting result is that a combination of the photovoltaic-gasoline-battery system is the most cost-effective energy system with a net present cost of $2,682. The system combination can lead to an emission reduction of approximately 98.3 per cent, compared to the use of gasoline generating sets, common mostly in SSA. If an amortized loan is used to purchase the energy system, and the payment plan is varied such that the frequency of payments is made quarterly, annually, semi-annually, bi-monthly, semi-monthly and bi-weekly, it will be observed that low-income household can conveniently acquire a HRES.

Originality/value

The result presented a framework by which a low-income household can purchase and install HRES. To facilitate this, it is recommended that low-income households should be given interest-friendly loans, so as to enhance the acquisition of HRES.

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Article
Publication date: 20 June 2019

Daniel Esene Okojie, Adisa Abdul-Ganiyu Jimoh, Yskandar Hamam and Adebayo Ademola Yusuff

This paper aims to survey the need for full capacity utilisation of transmission lines in power systems network operations. It proposes a review of the N-1 security criterion that…

143

Abstract

Purpose

This paper aims to survey the need for full capacity utilisation of transmission lines in power systems network operations. It proposes a review of the N-1 security criterion that does not ensure reliable dispatch of optimum power flow during outage contingency. The survey aims to enlarge the network capacity utilisation to rely on the entire transmission lines network operation.

Design/methodology/approach

The paper suggests transmission line switching (TLS) approach as a viable corrective mechanism for power dispatch. The TLS process is incorporated into a constraint programming language extension optimisation solver that selects the switchable line candidates as integer variables in the mixed integer programming problem.

Findings

The paper provides a practical awareness of reserve capacity in the lines that provide network security in outage contingency. At optimum power flow dispatch, the TLS is extended to optimal transmission line switching (OTLS) that indicates optimal capacity utilisation (OCU) of the available reserve capacity (ARC) in the network lines.

Practical implications

Computational efficiency influenced the extension of the OTLS to optimal transmission switching of power flow (OTSPF). The application of OTSPF helps reduce the use of flexible AC transmission systems (FACTS) and construction of new transmission lines..

Originality/value

The paper surveys TLS efforts in network capacity utilisation. The suggested ARC fulfils the need for an index with which the dispatchable lines may be identified for the optimal capacity utilisation of transmission lines network.

Details

Journal of Engineering, Design and Technology , vol. 17 no. 5
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 1 July 2002

Amar Khoukhi

In this paper the problem of the dynamic optimal time‐energy Off‐Line programming of an autonomous mobile robot in a crowded environment is considered. First, kinematic model and…

706

Abstract

In this paper the problem of the dynamic optimal time‐energy Off‐Line programming of an autonomous mobile robot in a crowded environment is considered. First, kinematic model and planning are presented. Then a dynamic model based on Euler‐Lagrange formalism is developed and a mobility estimation function of the robot is considered. This dynamic estimation of the robot mobility takes into account of the velocity and the orientation of the robot. Then the scene structuration and a path finder algorithm are developed. After, the optimal dynamic off‐line programming is formulated as a nonlinear programming problem under nonlinear equality and inequality constraints. The Discrete Augmented Lagrangian (DAL) is used to obtain the optimal trajectograhy. We develop an extended DAL to DALAP, DALAdaptive Penalty. RoboSim 1.0 simulator is developed to perform kinematic and DALAP based algorithms on a large class of mobile robots optimal time‐energy off‐line programming. A comparative study with kinematic planning is considered. It is shown that the performance of the dynamic optimal time‐energy control and off‐line programming is much better than kinematic and heuristic based schemes. This strategy of trajectory planning was implemented on the case study of the SARA mobile robot model.

Details

Kybernetes, vol. 31 no. 5
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 5 July 2013

A.B. Khalaf, Y. Hamam, Y. Alayli and K. Djouani

Studying the availability of medical equipment based on various maintenance types has been a major concern for hospitals. Most of the methodologies used are empirical and few are…

752

Abstract

Purpose

Studying the availability of medical equipment based on various maintenance types has been a major concern for hospitals. Most of the methodologies used are empirical and few are based on mathematical modelling. The objective of this paper is to present a mathematical maintenance model that analyses the effect of maintenance on the survival probability of medical equipment based on maintenance history and age of that equipment.

Design/methodology/approach

A global model is proposed to measure the probability of equipment being available using real data extracted from maintenance history of infusion pumps and ventilators and analysed using Matlab. To confirm the validity of the developed model, the survival analysis approach is used to develop a model that measures the survival of equipment as a function of maintenance and age of equipment. The method is first tested using simulated data and the findings confirm the validity of the proposed approach.

Findings

The analysis using survival approach reveals that conducting preventive maintenance (PM) on the selected medical equipment had an impact on survival of equipment. However, the manufacturer's recommended PM intervals do not correlate to the failure rate encountered. This will contribute to the debate on PM manufacturer's recommended intervals and might lead to the revision of maintenance strategies implemented by hospitals and clinical engineering (CE) practitioners.

Research limitations/implications

Although the data collected for the infusion pumps were quite sufficient, that collected for the ventilators were more limited. The major difficulty is that of the availability of historical maintenance data and the effect of user errors may cause uncertainty in the analysis. A closer collaboration with the medical professional should facilitate the recording and access to such information.

Practical implications

The use of mathematical modelling to analyse the effect of maintenance on the survival of medical equipment is a beneficial tool that is not exploited in the medical equipment industry. It will provide CE practitioners with scientific tool to analyse the effect of PM on the survival of medical equipment.

Originality/value

This paper presents a mathematical approach to analyse the effect of maintenance on the survival of medical equipment, which is crucial in the assessment of maintenance strategies implemented in the medical equipment industry.

Details

Journal of Engineering, Design and Technology, vol. 11 no. 2
Type: Research Article
ISSN: 1726-0531

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Book part
Publication date: 18 January 2024

Deejaysing Jogee, Manta Devi Nowbuth, Virendra Proag and Jean-Luc Probst

It is now well-established that good water quality is associated with economic prosperity, reduced incidence on public health and the good functioning of the various ecosystems…

Abstract

It is now well-established that good water quality is associated with economic prosperity, reduced incidence on public health and the good functioning of the various ecosystems found in our environment. Water contamination is mostly related to both diffused (agricultural lands and geologic rock degradations) and point sources of pollution. Mauritius has many water resources which depend solely on precipitation for their replenishment. Water parameters which are of relevance include total dissolved solids (TDS), temperature, pH, electrical conductivity, turbidity, dissolved oxygen, dissolved and particulate organic carbon and major cations and anions. The traditional methods of analysis for these parameters are mostly using electrical and optical methods (probes and sensors in the field), while chemical titrations, Flame AAS and High-Performance Liquid Chromatography techniques are carried out in the laboratory. Image Classification techniques using neural networks can also be used to detect the presence of contaminants in water. In addition to basic water quality parameters, the field sensors range have been extended to cover important major ions and can now be integrated with Artificial Intelligence (AI)-based models for the prediction of variations in water quality to better protect human health and the environment, reduce operation costs of water and wastewater treatment plant unit processes.

Details

Artificial Intelligence, Engineering Systems and Sustainable Development
Type: Book
ISBN: 978-1-83753-540-8

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Article
Publication date: 28 November 2018

Sophi Shilpa Gururajapathy, Hazlie Mokhlis and Hazlee Azil Illias

The purpose of this paper is to identify faults in distribution systems which are unavoidable because of adverse weather conditions and unexpected accidents. Hence, quick fault…

182

Abstract

Purpose

The purpose of this paper is to identify faults in distribution systems which are unavoidable because of adverse weather conditions and unexpected accidents. Hence, quick fault location is vital for continuous power supply. However, most fault location methods depend on the stored database for locating fault. The database is created by simulation, which is time consuming. Therefore, in this work, a comprehensive fault location method to detect faulty section and fault distance from one-ended bus using limited simulated data is proposed.

Design/methodology/approach

The work uses voltage sag data measured at a primary substation. Support vector machine estimates the data which are not simulated. The possible faulty section is determined using matching approach and fault distance using mathematical analysis.

Findings

This work proposed a ranking analysis for multiple possible faulty sections, and the fault distance is calculated using Euclidean distance approach.

Practical implications

The research work uses Malaysian distribution system as it represents a practical distribution system with multiple branches and limited measurement at primary substation. The work requires only metering devices to identify fault which is cost effective. In addition, the distribution system is simulated using real-time PSCAD by which the capability of proposed method can be fully tested.

Originality/value

The paper presents a new method for fault analysis. It reduces simulation time and storage space of database. The work identifies faulty section and ranks the prior faulty section. It also identifies fault distance using a mathematical approach.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 38 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 11 May 2020

Mehdi Jahangiri, Ahmad Haghani, Shahram Heidarian, Ali Mostafaeipour, Heidar Ali Raiesi and Akbar Alidadi Shamsabadi

Rural areas are one of the effective regions in economy and self-sufficiency field especially in agricultural and livestock section. Planning in the rural section and the effort…

247

Abstract

Purpose

Rural areas are one of the effective regions in economy and self-sufficiency field especially in agricultural and livestock section. Planning in the rural section and the effort in solving the problems of farmers lead to increase their interest in farming and manufacturing in the villages and decrease their migration to the cities and metropolitans. Therefore, the present study aimed at feasibility of electricity to a rural household in Iran using off-grid solar-based hybrid system.

Design/methodology/approach

In renewable energy projects, a successful evaluation requires suitable criteria so that one can properly analyze the operational behavior of all feasible scenarios. In the present paper, HOMER software has been used for this purpose for a village with no access to electricity grid (Bar Aftab-e Jalaleh, Iran). Due to drastic fluctuation of fossil fuel prices and varied solar radiations in various years because of climate change, sensitivity analysis has been performed using HOMER.

Findings

In the optimum status economically, 70% of needed energy is provided by solar cells at the price 0.792 $/kWh. The comparison between the optimum condition economically and the condition that only use fossil fuels revealed that the return on investment will occur after less than 2 years and have remained profitable over 23 years.

Social implications

The authors hope that the results of this study can be used in planning of the authorities to realize the interests of people in this village.

Originality/value

According to the surveys, despite Iran being the first country in terms of providing solar power to the villages, so far no socio-economic-environmental assessment has been done for a solar cell-based micro-grid in an off-grid mode for a remote village that is deprived of electricity from a national electricity grid. In addition, for the first time in Iran, the effect of the fuel price and solar radiation parameters variability on the performance of system have been investigated.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 6
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 14 May 2018

Hassana Mahfoud, El Barkany Abdellah and Ahmed El Biyaali

The purpose of this paper is to review maintenance strategies within the healthcare domain and to discuss practical needs as gaps between research and practice.

685

Abstract

Purpose

The purpose of this paper is to review maintenance strategies within the healthcare domain and to discuss practical needs as gaps between research and practice.

Design/methodology/approach

The paper systematically categorizes the published literature on clinical maintenance optimization and then synthesizes it methodically.

Findings

This study highlights the significant issues relevant to the application of dependability analysis in healthcare maintenance, including the quantitative and qualitative criteria taken into account, data collection techniques and applied approaches to find the solution. Within each category, the gaps and further research needs have been discussed with respect to both an academic and industrial perspective.

Practical implications

It is worth mentioning that medical devices are becoming more and more numerous, various and complex. Although, they are often affected by environmental disturbances, sharp technological development, stochastic and uncertain nature of operations and degradation and the integrity and interoperability of the supportability system, the associated practices related to asset management and maintenance in healthcare are still lacking. Therefore, the literature review of applied based research on maintenance subject is necessary to reveal the holistic issues and interrelationships of what has been published as categorized specific topics.

Originality/value

The paper presents a comprehensive review that will be useful to understand the maintenance problem and solution space within the healthcare context.

Details

Journal of Quality in Maintenance Engineering, vol. 24 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

Available. Open Access. Open Access
Article
Publication date: 28 July 2023

Guido Veronese, Anas Ismail, Fayez Mahamid, Basel El-Khodary, Dana Bdier and Marwan Diab

This study aims to explore the effect of mental health in terms of depression, anxiety, stress, fear of COVID-19 and quality of life (QoL) on the reluctance to be vaccinated in a…

1012

Abstract

Purpose

This study aims to explore the effect of mental health in terms of depression, anxiety, stress, fear of COVID-19 and quality of life (QoL) on the reluctance to be vaccinated in a population of Palestinian adults living in occupied Palestinian territories and Israel.

Design/methodology/approach

The authors recruited 1,122 Palestinian adults who consented to participate in the study; 722 were females, and the mean age of the sample was 40.83 (SD 8.8). Depression, anxiety, and stress scale (DASS), World Health Organization QoL-BREF, FCov-19 and reluctance to the vaccine scale were administered; hierarchical regression analysis was applied to test vaccine reluctance as a dependent variable, and mental health, fear of COVID-19 and QoL as independent variables. This study hypothesized influence of such variables on the vaccine choice with differences due to the participants’ geographical locations.

Findings

Findings showed an effect of mental health, particularly depression, QoL and fear of COVID on vaccine reluctance, with depression and fear of COVID in the West Bank and Gaza, while in Israel, QoL played a role in vaccination choices.

Research limitations/implications

The future needs to be comprehended more thoroughly to discover mutations and fluctuations over time in vaccine hesitancy and the increasing role of psychological distress, diminished QoL and fear of Covid-19. Online recruitment might not have allowed the study to include the most disadvantaged strips of the Palestinian population.

Practical implications

Human rights perspectives must be considered in public health and public mental health policies to ensure the QoL and well-being for the Palestinian population during and following the pandemic.

Social implications

The crumbling of the Palestinian health-care system exacerbated the sense of dread among the population and made them less likely to vaccinate. The pandemic-like spread of Covid-19 prompts a plea for the global community to actively advocate for the urgent re-establishment of equity, autonomy and durability of the medical infrastructure in the occupied territories and equal entitlements for the Palestinians in Israel.

Originality/value

The results demonstrated the importance for public mental health to consider the multiple levels implied in the vaccine refusal in Palestine and Israel among the Palestinian population.

Details

Journal of Public Mental Health, vol. 22 no. 4
Type: Research Article
ISSN: 1746-5729

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Article
Publication date: 11 January 2024

Yuepeng Zhang, Guangzhong Cao, Linglong Li and Dongfeng Diao

The purpose of this paper is to design a new trajectory error compensation method to improve the trajectory tracking performance and compliance of the knee exoskeleton in…

144

Abstract

Purpose

The purpose of this paper is to design a new trajectory error compensation method to improve the trajectory tracking performance and compliance of the knee exoskeleton in human–exoskeleton interaction motion.

Design/methodology/approach

A trajectory error compensation method based on admittance-extended Kalman filter (AEKF) error fusion for human–exoskeleton interaction control. The admittance controller is used to calculate the trajectory error adjustment through the feedback human–exoskeleton interaction force, and the actual trajectory error is obtained through the encoder feedback of exoskeleton and the designed trajectory. By using the fusion and prediction characteristics of EKF, the calculated trajectory error adjustment and the actual error are fused to obtain a new trajectory error compensation, which is feedback to the knee exoskeleton controller. This method is designed to be capable of improving the trajectory tracking performance of the knee exoskeleton and enhancing the compliance of knee exoskeleton interaction.

Findings

Six volunteers conducted comparative experiments on four different motion frequencies. The experimental results show that this method can effectively improve the trajectory tracking performance and compliance of the knee exoskeleton in human–exoskeleton interaction.

Originality/value

The AEKF method first uses the data fusion idea to fuse the estimated error with measurement errors, obtaining more accurate trajectory error compensation for the knee exoskeleton motion control. This work provides great benefits for the trajectory tracking performance and compliance of lower limb exoskeletons in human–exoskeleton interaction movements.

Details

Robotic Intelligence and Automation, vol. 44 no. 1
Type: Research Article
ISSN: 2754-6969

Keywords

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