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In recent times, electricity as one of the most important energy sources has witnessed considerable decreases in consumption figures. These cutbacks have been mainly due to the growing increasing living standards, minimal governance and political fracture. Thus, this paper aims to appraise the supply of electricity side in an attempt to propose a sustainable electricity framework.

The reviewed literature identified a gap within the previous literature which had not previously been investigated; however, to carry out the investigation, a research strategy had to be formulated. Twenty semi-structured interviews were carried out with managers, engineers and electrical professionals. Prior to the commencement of the main study, a preliminary pilot study was carried out among ten senior practitioners in the General Electric Company of Libya. The purpose of the pilot study was to assess clarity of questions, timing and suitability of the respondents for the study, and to establish its reliability and validity.

From the aspect of the demand, the study found that there was a diverse set of factors that affect electricity demand in Libya. These included the average real price of electricity, the real value of the imported electrical appliances, gross domestic product, population, the temperature difference and the lagged electricity demand. Secondly, from the aspect of electricity supply, the study found that there was a diverse set of factors that affect electricity projects in Libya or even the development of existing projects. These factors included electricity demand, political effects, recession, oil prices and improved development of other infrastructure.

Due to limitations in time and cost, political instability in the country and the lack of security, the entire analysis was only of the demand for electricity in Libya based on data collected from secondary sources and primary data resources. The ordinary least squares method of regression used for the purpose of quantitative analysis only included the factors related to the demand for electricity in Libya. It is worth noting that the research work did not include any quantitative analysis that comprised factors related to the supply of electricity in the country. Such an analysis could have technically carved the ways to augment the supply of electricity. Therefore, the context of the research work is one-sided that focuses primarily on the demand.

The problem confronting development of electricity projects in Libya has three components: The first is the national significance of the projects as a physical resource. The second is the conflict arising politically from within. The third is the lack of consideration given to the specific resource management issues associated with the projects within the government plans and policy statements. In addition, participants further claimed that there were three more independent factors that could affect the level of electricity demand in Libya. These were urbanisation, industrialisation and literacy rates.

The participants also believed that as the rate of socio-economic development increases, the demand for electricity is expected to rise. Urbanisation, industrialisation and literacy rates are some of the developments which will exert more demand pressure on the electricity supply. The participants claimed that the government should take into account the urbanisation rates in Libya in the energy policy formulation. Electricity companies can also take a cue from the urbanisation trends and other socio-economic developments to plan the delivery of electricity according to the rising demand.

This study appraised the supply of electricity side in Libya and proposed a sustainable framework that could be used by policymakers to address energy demand issues in Libya.

The purpose of this study is to improve the control performance of grid-connected photovoltaic (PV) inverters with inductive-capacitive-inductive (LCL) filters by proposing a new robust current control based on uncertainty and disturbance estimator (UDE).

The control strategy combines the capacitor current feedback with a UDE-based control to solve robust stability issues in the presence of parametric uncertainties and disturbances.

This paper provides guidelines for tuning the controller parameters where it is shown to be easy to implement by simply selecting the appropriate feedback coefficient, the reference model and an approximate lumped disturbance bandwidth. Simulation and experimental results demonstrate the effectiveness of the proposed controller in terms of resonance damping, tracking performance and robust stability under grid uncertainties and disturbances.

This paper offers a new approach for designing implementable robust controllers for LCL-filtered grid-connected PV inverters.

A new UDE-based current control is proposed to improve the stability performance of grid-connected PV inverters. The advantages of UDE-based control are its simple structure, easy tuning and robustness under parameter uncertainties and disturbances. Simulation and experimental results support the theoretical findings.

This paper aims to report a novel preparation method of ZnO particles with different structures and their photocatalytic activity.

ZnO powders are prepared by a facile, economical and environment-friendly aqueous solution route. X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectra are used to characterize the products. Photocatalytic activity of the samples is evaluated by degradation of organic pollutant pentachlorophenol under UV-vis irradiation.

It is found that three-dimensional ZnO hierarchical structures can be prepared via aqueous solution route without using any template or structure-directing agent, and the alkalinity of reaction solution is the key factor. All the as-prepared ZnO products have good catalytic activity under UV-vis light irradiation.

This report presents a simple method for the preparation of ZnO particles with excellent photocatalytic activity. Experimental results could provide useful reference for the treatment of chlorophenols in the future.

This paper aims to report a novel preparation method of titanium dioxide (TiO₂)/zinc oxide (ZnO) composites with different mole ratios of TiO₂:ZnO and their photocatalytic activity.

TiO₂/ZnO composites are prepared by a facile route. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and ultra-violet–visible diffuse reflectance spectra (UV-vis DRS) are used to characterize the products. Photocatalytic activity of the samples is evaluated by degradation of persistent organic pollutant pentachlorophenol under ultra-violet (UV) irradiation.

It is found that all the as-prepared TiO₂/ZnO composites not only have good catalytic activity under UV light irradiation, but also have excellent circulation stability. The optimal mole ratio of TiO₂:ZnO is 0.75:1.

This report presents a simple and rapid method for the preparation of TiO₂/ZnO composites with excellent photocatalytic activity. Experimental results could provide useful reference for the treatment of chlorophenols in the future.

Energy is the major concern in wireless sensor networks (WSNs) for most of the applications. There exist many factors for higher energy consumption in WSNs. The purpose of this work is to increase the coverage area maintaining the minimum possible nodes or sensors.

This paper has proposed multilayer (ML) nodes deployment with distributed MAC (DS-MAC) in which nodes listen time is controlled based on communication of neighbors. Game theory optimization helps in addressing path loss constraints while selecting path toward base stations (BS).

The simulation is carried out using NS-2.35, and it shows better performance in ML DS-MAC compared to random topology in DS-MAC with same number of BS. The proposed method improves performance of network in terms of energy consumption, network lifetime and better throughput.

Energy consumption is the major problem in WSNs and for which there exist many reasons, and many approaches are being proposed by researchers based on application in which WSN is used. Node mobility, topology, multitier and ML deployment and path loss constraints are some of the concerns in WSNs.

Game theory is used in different situations like countries whose army race, business firms that are competing, animals generally fighting for prey, political parties competing for vote, penalty kicks for the players in football and so on.

WSNs find applications in surveillance, monitoring, inspections for wild life, sea life, underground pipes and so on.

Game theory optimization helps in addressing path loss constraints while selecting path toward BS.

The purpose of this study is to numerically and experimentally survey the thermal efficiency of a block-type heat exchanger operated in different working conditions by using pure water and two nanofluids as heat transfer fluids.

An aluminum block-type heat exchanger integrated with Peltier thermoelectric element was designed and installed to operate in a cycle, and the thermal performance of the heat exchanger, heat transfer rate, Nusselt and heat transfer coefficient variations were examined at different bath water temperatures by using recycled nanofluids. New generation surface-modified Fe₃O₄@SiO₂-mix-(CH₂)₃Cl@Imidazol/water nanofluid was used as heat transfer fluid in the cycle. In addition, CFD simulation was performed using ANSYS/Fluent to investigate the temperature distribution and fluid flow structure in the used heat exchanger.

Experiments were carried out by using numerical and experimental methods. In the experiments, the operating conditions such as flow rate, volume fraction of the nanofluid and water bath temperature were changed to find the effect of each parameter on the thermal efficiency. The Reynolds number varied depending on the test conditions, which was calculated in the range of approximately 100 < Re < 350. In addition, Nusselt number and heat transfer coefficient of test fluids were very close to each other. For 0.4% nanofluid, the maximum h value was obtained as 3837.1, when the Reynolds number was measured as 314.4.

In the scientific articles published in the field of heat exchangers operated by nanofluids, little attention has been paid to the stability of the nanofluids and sedimentation of particles in the base fluids. In addition, in most cases, experiments were implemented using an electrical resistance as a heat source. In this research, stable surface-modified nanofluids were used as heat transfer fluids, and it was found that the Peltier thermoelectric can be used as heat sources with acceptable efficiency in flat-type heat exchangers and even non-circular channels.

A new cutting tool is always well-defined and sharp at the onset of the metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of the service period of the cutting tool while machining. It is significant to provide a corresponding real-time varying damping to control this chatter, which directly influences accuracy and quality of productivity. This paper aims to review the literature related to the application of smart fluid to control vibration in metal cutting and also focused on the challenges involved in the implementation of active control system during machining process.

Smart dampers, which are used as semi-active and active dampers in metal cutting, were reviewed and the research studies carried out in the field of the magnetorheological (MR) damper were concentrated. In smart materials, MR fluids possess some disadvantages because of their sedimentation of iron particles, leakage and slow response time. To overcome these drawbacks, new MR materials such as MR foam, MR elastomers, MR gels and MR plastomers have been recommended and suggested. This review intents to throw light into available literature which exclusively deals with controlling chatter in metal cutting with the help of MR damping methods.

Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration. In the past, many researchers have attempted to implement MR damper in metal cutting to control vibration and were successful. Various methods with the help of MR fluid are illustrated.

A new cutting tool is always well-defined and sharp at the onset of metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of service period of cutting tool while machining. Application of MR damper along with the working methodology in metal cutting is presented, challenges met are analyzed and a scope for development is reviewed.

This study provides corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity. Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration.

This study attempts to implement smart damper in metal cutting to control vibrations.

It is significant to provide corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

The purpose of this paper is to examine the efficacy of knowledge management (KM) based systems and best practices that could be used to address operational issues in the oil and gas sector.

Given little was known empirically about the strategies and practices which contribute to improved performance, innovation and continuous improvement in the oil and gas sector qualitative method was used. Semi-structured interviews were used to derive senior managers’ constructs of project delivery efficiency and KM based systems. The interviews were analysed through the use of a qualitative analysis software package NUDIST NVivoTM. Participants were selected using purposive sampling. Validity and reliability were achieved by first assessing the plausibility in terms of already existing knowledge on some of the operational issues raised by participants.

These were synthesised into a framework capturing seven well-defined stages. All these steps emerged as being related; they are comprised of independent variables. These steps were found to comprise of knowledge management technology approaches, knowledge management people approaches, KM strategies and value enhancing practices.

Although the findings are pertinent to oil and gas organisations, it will be important to conduct follow-up research validating the potential for using the results of this study to establish frameworks for knowledge and information management in different organisations and contexts. This will provide not only data about the validity of the framework in generic terms but will also generate additional data on the application of KM strategy.

As shown in this study, successful KM based systems requires the aligning of business strategy, technology for KM, project management operations with an enterprise knowledge-sharing culture. Such sharing requires managing the behaviour of project personnel such that knowledge transfer becomes part of the organisation’s norm.

The implementation of KM based systems requires deliberate planning and action to create the conditions for success and put in place the strategy, leadership, goals, process, skills, systems, issue resolution, and structure to direct and exploit the dynamic nature of project work. The strategies proposed in this research cannot be expected to resolve all KM issues in the oil and gas sector. However, their use defines an approach that is superior to the traditional approaches typically adopted and consequently merits far wider application.

The proposed framework presents a better way of optimising the performance of project-based operations thus enabling oil and gas organisations to reform their poor performance on projects and empower them to better manage emerging cultural challenges in their future projects. Reflecting on their experiences, the participants confirmed that the proposed KM framework and its seven well-defined stages were central to the effectiveness of KM in oil and gas operations. Although the scope of this research was restricted to projects in Nigeria and the UK, the geographical focus of this research does not invalidate these results with respect to other countries. The fact is that the oil and gas sector globally shares some common fundamental characteristics.

The purpose of this paper is to investigate the magnetic properties and the ground state phase diagrams of the double perovskite La₂NiMnO₆ using the Monte Carlo simulations (MCS).

In this work, the authors propose a Hamiltonian modeling this compound, described by an Ising model, with different exchange coupling interactions J11, J12 and J22 between the only magnetic atoms Ni and Mn.

Starting with the ground state phase diagrams, the authors present and discuss the stable configurations in different physical parameter planes. On the other hand, the authors present the investigation of the magnetic properties and the magnetization behaviors of the magnetic susceptibilities, as a function of temperature, crystal field, the exchange coupling interactions and the Zeeman energy. To complete this study, the authors illustrate the dependency of the total magnetizations for the hysteresis loops of the double perovskite La₂NiMnO₆ compound. This study is done for fixed values of temperature, the exchange coupling interactions and crystal field.

The authors modeled the different physical parameters of the double perovskite La₂NiMnO with a Hamiltonian describing the system. At T=0K, the authors discussed the ground state phase diagrams of different physical parameters planes. For non-null temperature values, the authors studied the magnetic behavior of the double perovskite La₂NiMnO using MCS under the metropolis algorithm. The authors expect that the results of these simulations can provide some important keys for the experimental research and technology applications of the double perovskite La₂NiMnO₆ in the future.