• Design, Simulation, Analysis and Optimization of PID and Fuzzy Based Control Systems for a Quadcopter

      Leal, Isaac S.; orcid: 0000-0002-3351-0491; email: isaac.sanchezleal@miun.se; Abeykoon, Chamil; orcid: 0000-0002-6797-776X; email: chamil.abeykoon@manchester.ac.uk; Perera, Yasith S.; orcid: 0000-0002-1988-2766; email: yasiths@uom.lk (MDPI, 2021-09-10)
      Unmanned aerial vehicles or drones are becoming one of the key machines/tools of the modern world, particularly in military applications. Numerous research works are underway to explore the possibility of using these machines in other applications such as parcel delivery, construction work, hurricane hunting, 3D mapping, protecting wildlife, agricultural activities, search and rescue, etc. Since these machines are unmanned vehicles, their functionality is completely dependent upon the performance of their control system. This paper presents a comprehensive approach for dynamic modeling, control system design, simulation and optimization of a quadcopter. The main objective is to study the behavior of different controllers when the model is working under linear and/or non-linear conditions, and therefore, to define the possible limitations of the controllers. Five different control systems are proposed to improve the control performance, mainly the stability of the system. Additionally, a path simulator was also developed with the intention of describing the vehicle’s movements and hence to detect faults intuitively. The proposed PID and Fuzzy-PD control systems showed promising responses to the tests carried out. The results indicated the limits of the PID controller over non-linear conditions and the effectiveness of the controllers was enhanced by the implementation of a genetic algorithm to autotune the controllers in order to adapt to changing conditions.
    • Prospects of Integrated Photovoltaic-Fuel Cell Systems in a Hydrogen Economy: A Comprehensive Review

      Ogbonnaya, Chukwuma; orcid: 0000-0003-4756-6485; email: chukwuma.ogbonnaya@manchester.ac.uk; Abeykoon, Chamil; orcid: 0000-0002-6797-776X; email: chamil.abeykoon@manchester.ac.uk; Nasser, Adel; orcid: 0000-0003-1609-1384; email: a.g.nasser@manchester.ac.uk; Turan, Ali; orcid: 0000-0001-9225-6668; email: a.turan@ntlworld.com; Ume, Cyril Sunday; email: cyril.ume@funai.edu.ng (MDPI, 2021-10-19)
      Integrated photovoltaic-fuel cell (IPVFC) systems, amongst other integrated energy generation methodologies are renewable and clean energy technologies that have received diverse research and development attentions over the last few decades due to their potential applications in a hydrogen economy. This article systematically updates the state-of-the-art of IPVFC systems and provides critical insights into the research and development gaps needed to be filled/addressed to advance these systems towards full commercialization. Design methodologies, renewable energy-based microgrid and off-grid applications, energy management strategies, optimizations and the prospects as self-sustaining power sources were covered. IPVFC systems could play an important role in the upcoming hydrogen economy since they depend on solar hydrogen which has almost zero emissions during operation. Highlighted herein are the advances as well as the technical challenges to be surmounted to realize numerous potential applications of IPVFC systems in unmanned aerial vehicles, hybrid electric vehicles, agricultural applications, telecommunications, desalination, synthesis of ammonia, boats, buildings, and distributed microgrid applications.
    • The Impact of the Performance Appraisal Process on Job Satisfaction of the Academic Staff in Higher Educational Institutions

      Dasanayaka, Chamila H.; email: chamila.dasanayaka@uni.cumbria.ac.uk; Abeykoon, Chamil; orcid: 0000-0002-6797-776X; email: chamil.abeykoon@manchester.ac.uk; Ranaweera, R. A. A. S.; orcid: 0000-0002-7404-196X; email: achala@kln.ac.lk; Koswatte, Isuru; orcid: 0000-0002-1807-1996; email: isuru.k@nsbm.ac.lk (MDPI, 2021-10-11)
      Performance appraisal is one of the key management tools which identifies employees’ strengths and weaknesses. Usually, this is the major mechanism of gathering information for rewarding/training employees based on their performance, and hence a key to achieve organisational goals by creating a satisfied workforce. Therefore, this study was aimed at examining the effects of the Performance Appraisal Process on job satisfaction of the university academic staff. The information collected within one of the largest universities in the UK via questionnaires and semi-structured interviews showed that the existing appraisal process majorly aligned with the requirements of the research-excellence-framework of the UK, which is greatly concerned with research rather than teaching. Furthermore, it was found that there is no clear link between promotions, salary increments, and rewards, etc. with staff performance within the current appraisal process. Eventually, it was realised that the majority of the academic staff of the source university were dissatisfied with the current performance appraisal process, and this could be the situation in the majority of universities in the UK. Therefore, further research in this area is highly recommended to explore extensive information to create a favourable work/study environment for both staff and students within the universities.