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Article
Publication date: 12 April 2018

R. Masrour, M. Ben Ali, H. El Moussaoui, Mohamed Hamedoun, A. Benyoussef and E.K. Hlil

The purpose of this paper is to synthesize the manganese ferrite nanoparticle MnFe2O4 and to investigate the structure, size and to study the electronic and the magnetic…

153

Abstract

Purpose

The purpose of this paper is to synthesize the manganese ferrite nanoparticle MnFe2O4 and to investigate the structure, size and to study the electronic and the magnetic properties of MnFe2O4 nanoparticles.

Design/methodology/approach

The co-precipitation method is used to synthesize the MnFe2O4. The structure and size were investigated by X-ray diffraction. The superconducting quantum interference device is used to determine the some magnetic ground. From theoretical investigation point of view self-consistent ab initio calculations, based on density functional theory approach using full potential linear augmented plane wave method, were performed to investigate both electronic and magnetic properties of the MnFe2O4. The high temperatures series expansion (HTSE) is used to study the magnetic properties of MnFe2O4.

Findings

The saturation magnetization, the coercivity and the transition temperature varied between 21-43 emu/g, 20-50 Oe and 571-630 K, respectively, have been studied. The gap energy of MnFe2O4 has been deduced. The critical temperature and the critical exponent have been obtained using HTSEs.

Originality/value

In the present work, the authors study the electronic and magnetic properties of MnFe2O4. The results obtained by the experiment and by ab initio calculations were used in HTSE as input to deduce other physical parameters.

Details

Multidiscipline Modeling in Materials and Structures, vol. 14 no. 4
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 3 December 2021

Haris Calgan

This study aims to design and implement a novel tilt integral sliding mode controller and observer for sensorless speed control of a permanent magnet synchronous motor (PMSM).

322

Abstract

Purpose

This study aims to design and implement a novel tilt integral sliding mode controller and observer for sensorless speed control of a permanent magnet synchronous motor (PMSM).

Design/methodology/approach

A control strategy combining the tilt integral derivative (TID) with sliding mode control (SMC) is proposed to determine the tilt integral sliding mode manifold. Using this manifold, tilt integral sliding mode controller (TISMC) and observer (TISMO) are designed. The stabilities are verified by using Lyapunov method. To prove the effectiveness and robustness of proposed methods, sensorless speed control of PMSM is performed for various operating conditions such as constant and variable speed references, load disturbance injection, parameter perturbation, whereas sensor noises are not taken into account. The performance of proposed method is compared with TID controller, proportional integral derivative controller and conventional SMO.

Findings

Simulation results demonstrate that TISMC and TISMO have better performance in all operating conditions. They are robust against parameter uncertainties and disturbances. TISM based sensorless control of PMSM is well guaranteed with superior performance.

Originality/value

The proposed method has not been tackled in the literature. By combining TID and SMC, novel tilt integral sliding manifold is presented and used in designing of the controller and observer. It is proven by Lyapunov method that errors converge to zero.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 18 March 2020

Rachid Aharrouch, Karima El Kihel, Mohamed Madani, Nabil Hachem, Amer Lafhal and Mohammed El Bouziani

The purpose of this paper is to study the magnetic properties and the hysteresis behavior of a ferrimagnetic cubic Ising nanowire with mixed spins S = 3/2 and S = 5/2 in which the…

82

Abstract

Purpose

The purpose of this paper is to study the magnetic properties and the hysteresis behavior of a ferrimagnetic cubic Ising nanowire with mixed spins S = 3/2 and S = 5/2 in which the atoms are placed alternately.

Design/methodology/approach

In order to investigate the effects of the exchange interactions and crystal field on the magnetic properties and hysteresis behavior of the nanowire, we have used the Monte Carlo simulation. More precisely, we have plotted the thermal variations of the sublattice and total magnetizations for different values of the Hamiltonian parameters, and we have presented the corresponding phase diagrams. In addition, the influence of an external magnetic field is examined by plotting the variations of hysteresis loops with the change of temperature and crystal field.

Findings

All phase transition found in this study are of second-order and the critical temperatures increase linearly with the increase of the exchange interactions. The compensation temperatures appear only for some domains of crystal field D and exchange interaction JB of the sublattice (B). Moreover, when studying the hysteresis behavior, the system can show one or double hysteresis loops.

Originality/value

The authors consider that this research is consistent with the scientific axis of the journal which benefits a great esteem in our country and in the world. In addition, the results are of technological interest.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 5
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 16 June 2023

Haider Jouma Touma, Muhamad Mansor, Muhamad Safwan Abd Rahman, Yong Jia Ying and Hazlie Mokhlis

This study aims to investigate the feasibility of proposed microgrid (MG) that comprises photovoltaic, wind turbines, battery energy storage and diesel generator to supply a…

93

Abstract

Purpose

This study aims to investigate the feasibility of proposed microgrid (MG) that comprises photovoltaic, wind turbines, battery energy storage and diesel generator to supply a residential building in Grindelwald which is chosen as the test location.

Design/methodology/approach

Three operational configurations were used to run the proposed MG. In the first configuration, the electric energy can be vended and procured utterly between the main-grid and MG. In the second configuration, the energy trade was performed within 15 kWh as the maximum allowable limit of energy to purchase and sell. In the third configuration, the system performance in the stand-alone operation mode was investigated. A whale optimization technique is used to determine the optimal size of MG in all proposed configurations. The cost of energy (COE) and other measures are used to evaluate the system performance.

Findings

The obtained results revealed that the first configuration is the most beneficial with COE of 0.253$/KWh and reliable 100%. Furthermore, the whale optimization algorithm is sufficiently feasible as compared to other techniques to apply in the applications of MG.

Originality/value

The value of the proposed research is to investigate to what extend the integration between MG and main-grid is beneficial economically and technically. As opposed to previous research studies that have focused predominantly only on the optimal size of MG.

Details

International Journal of Energy Sector Management, vol. 18 no. 4
Type: Research Article
ISSN: 1750-6220

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Article
Publication date: 28 July 2021

Maksym Kraiev, Eugene Voronkov and Violeta Kraieva

The purpose is to calculate the change in the total energy of a small fragment of an idealized lattice of iron (in its pure form and with impurity atoms) containing an edge…

43

Abstract

Purpose

The purpose is to calculate the change in the total energy of a small fragment of an idealized lattice of iron (in its pure form and with impurity atoms) containing an edge dislocation during its elementary motion at one interatomic spacing, both under the influence of a constant magnetic field and without it. The introduction of a magnetic field into the system is aimed at checking the adequacy of the description of the phenomenon of magnetoplasticity by changing the total energy of the atomic system.

Design/methodology/approach

The design procedure is based on a quantum-mechanical description of the switching process of the covalent bond of atoms in the dislocation core. The authors used the method of density functional theory in the Kohn-Shem version, implemented in the GAUSSIAN 09 software package. Using the perturbation theory, the authors modeled the impact of an external constant magnetic field on the energy of a system of lattice atoms.

Findings

The simulation results confirmed the effect of an external constant magnetic field on the switching energy of the covalent bond of atoms in the dislocation core, and also a change in the magnetic susceptibility of a system of atoms with a dislocation. This complements the description of the magnetoplastic effect during the deformation of metals.

Originality/value

The authors created quantum-mechanical models of the dislocation motion in the Fe crystal lattice: without impurities, with a substitutional atom Cr and with an interstitial atom C. The models take into account the influence of an external constant magnetic field.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 6
Type: Research Article
ISSN: 1573-6105

Keywords

Available. Open Access. Open Access
Article
Publication date: 13 June 2023

Alaa Eddine El Moussaoui and Brahim Benbba

This paper aims to determine the factors that influence the consumer’s online shopping intention in the current pandemic context (COVID-19). For this purpose, a conceptual model…

3658

Abstract

Purpose

This paper aims to determine the factors that influence the consumer’s online shopping intention in the current pandemic context (COVID-19). For this purpose, a conceptual model has been developed by introducing the constructs “attitude,” “perceived utility,” “intention” as well as the variable “perceived risk of contagion.”

Design/methodology/approach

After collecting data from the questionnaire diffused in Moroccan e-commerce websites, this study used various statistical analyses with the multiple regression model on the SPSS statistical software to confirm or refute the research hypotheses.

Findings

The results indicate that attitude and perceived utility positively affect online shopping intention. However, the variable “perceived risk of contagion” has a weak effect on such intention, which can be explained by the period in which the survey was started (a few months after the confinement).

Originality/value

The scientific contribution of this study lies in the insertion of a new factor that will be called “perceived risk of contagion” in the research model. This factor has been inspired by the perceived risk theory of Bauer (1960). Furthermore, all studies dealing with this topic have been carried out in developed countries, such as France, Great Britain, Germany and the USA. For this reason, the researcher believe that it is more appropriate to study the intention to buy online during the COVID-19 pandemic in one of the developing countries, such as Morocco. This is based on the fact that to develop theories, it is necessary to examine a given problem in several countries. The context plays a determining role in such situations.

Details

Journal of Electronic Business & Digital Economics, vol. 2 no. 1
Type: Research Article
ISSN: 2754-4214

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Article
Publication date: 12 November 2024

Bilal En-Nouaary, Rania Beniaich and Aziz Hmioui

The purpose of the study is to examine the electricity generation potential of different renewable energy sources in Morocco, as well as to propose a novel decision support model…

23

Abstract

Purpose

The purpose of the study is to examine the electricity generation potential of different renewable energy sources in Morocco, as well as to propose a novel decision support model to prioritize renewable energy alternatives. The aim is to provide recommendations that support Morocco’s energy transition strategy and assist policymakers in devising future sustainable energy policies.

Design/methodology/approach

The paper integrates the analytic hierarchy process with expert feedback to prioritize five renewable energy alternatives – solar photovoltaics (PV), concentrated solar panels (CSP), wind, hydro and biomass – specific to the Moroccan context. The model uses 14 sub-criteria clustered into four main categories: economic, technological, socio-political and environmental. The criteria were weighted based on inputs from local energy sector experts to capture the distinct priorities and contextual specificities of Morocco’s renewable energy landscape.

Findings

The study’s findings emphasize the dominance of economic criteria among Moroccan experts. Solar PV emerged as the most suitable option due to its cost-effectiveness and alignment with Morocco’s policies to support solar energy, followed by hydropower and wind. CSP and biomass ranked lowest due to high costs and limited viability.

Research limitations/implications

This study highlighted the need for quality data to support informed decision-making, as well as for a centralized database to facilitate access to consistent information on renewable energy projects.

Practical implications

It is recommended that policymakers prioritize mature and cost-effective technologies by establishing supportive regulatory frameworks and expanding investments in hybrid renewable energy infrastructures.

Originality/value

In addition to introducing the Analytic Hierarchy Process model for the first time within the Moroccan context, to the best of the authors’ knowledge, this research draws recommendations to assist Moroccan policymakers in devising future sustainable policies for the energy sector.

Details

International Journal of Energy Sector Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1750-6220

Keywords

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Article
Publication date: 8 October 2024

Alaa Eddine El Moussaoui

In previous years, there has been a peak in deliveries from all sectors. Consequently, the number of transport vehicles on urban roads has also increased. Unsurprisingly, this…

48

Abstract

Purpose

In previous years, there has been a peak in deliveries from all sectors. Consequently, the number of transport vehicles on urban roads has also increased. Unsurprisingly, this increase leads to many environmental problems, including increased carbon emissions. This paper attempts to examine this issue by addressing the impact of logistics pooling on the reduction of CO2 emissions in last-mile logistics. The aim is to see which of the logistics pooling options can minimize more CO2 emissions and in particular reach the threshold fixed by the Moroccan Agency of Logistics Development which is 30% until 2030.

Design/methodology/approach

The author conducted a simulation study. The sample was chosen from the economic pillar of the Moroccan Kingdom, namely Casablanca.

Findings

The results indicate that two pooling strategies lead to a higher level of environmental performance compared to the objective set up by the Moroccan Agency of Logistics Development (Direct Upstream and Downstream Transport: 44.39%/Multi-pick Upstream Transport and Multi-drop Downstream Transport: 30.93%). However, the first strategy remains the best one, as it not only minimizes emissions but also reflects the practices already implemented by several carriers and logistics service providers.

Practical implications

Successfully implementing these strategies in Casablanca could serve as a model for other cities facing similar challenges, demonstrating the viability and benefits of logistics pooling. Ultimately, the reduction in CO2 emissions aligns with global environmental goals, contributing to the fight against climate change and promoting a healthier urban environment for residents. By leveraging simulation technology, Casablanca can make significant strides toward more sustainable and efficient last-mile logistics, setting a precedent for green urban logistics practices.

Originality/value

Given Morocco’s significant geostrategic position, the urban logistics sector plays a crucial role in the development of Arab countries. The findings of this study can offer valuable insights for policymakers aiming to achieve sustainable economic growth. Additionally, to the author’s knowledge, this is the first study to focus on logistics pooling and carbon emissions in Arab nations. The paper further contributes by highlighting important directions for future research.

Details

Management & Sustainability: An Arab Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2752-9819

Keywords

Available. Open Access. Open Access
Article
Publication date: 14 November 2024

Alaa Eddine El Moussaoui

In recent years, the concept of logistics clusters has attracted the attention of several researchers and practitioners. It is an agglomeration of different types of companies and…

126

Abstract

Purpose

In recent years, the concept of logistics clusters has attracted the attention of several researchers and practitioners. It is an agglomeration of different types of companies and operations, notably those providing logistics services, such as supply chain organization, storage and distribution. The paper focuses on this concept by examining the factors influencing LSPs to enter the logistics clusters.

Design/methodology/approach

An exploratory qualitative study based on semi-structured interviews was conducted. Regarding the sample size, the author interviewed 31 professionals belonging to logistics clusters located in the Moroccan economic metropolis of Casablanca.

Findings

The results show that the cost reduction, the reputation of the cluster, the learning from other LSPs, the communal services, the geographical proximity and the role of public authorities are the main factors impacting the entry of logistics service providers into these clusters.

Originality/value

This theme has never been investigated. Therefore, this research expands the literature review and tries to examine this gap of literature by studying the factors that can affect the adhesion of logistics service providers to these clusters.

Details

Arab Gulf Journal of Scientific Research, vol. 42 no. 4
Type: Research Article
ISSN: 1985-9899

Keywords

Available. Open Access. Open Access
Article
Publication date: 4 May 2021

Osama F. Al Kurdi

The Arab world is made up of 22 countries in the Middle East and North Africa. These countries are subjected to many social, economic, political and geographical vulnerabilities…

8579

Abstract

Purpose

The Arab world is made up of 22 countries in the Middle East and North Africa. These countries are subjected to many social, economic, political and geographical vulnerabilities contributing to increased risks or ineffective emergency and disaster management. This paper examines these vulnerabilities, how they may impact the country's ability to face disasters, and how they can improve disasters' overall management.

Design/methodology/approach

The author selected Qatar, Oman to represent the Arab oil-rich countries, while Jordan, Egypt and Morocco to represent non-oil rich countries. The research was conducted in a qualitative, inductive systematic literature review based on a well-established systematic literature review methodology. Selected literature was based on its recency and the countries in question.

Findings

The review reveals population gaps that could threaten the social system in the event of a disaster in countries like Qatar and Oman. The majority of the countries lack community engagement and pre-planning for emergency preparedness due to social and cultural barriers. Other nations like Jordan, Egypt and Morocco are prone to long-lasting economic challenges due to lack of resources, mismanagement or corruption. The paper also highlights the need to raise the educational attainment among citizens to understand disaster risk reduction.

Originality/value

This study utilized the research method developed by Williams et al. (2017) to present a comprehensive systematic and comparative review of disaster management in the Arab world. Considering that disaster and emergency management has remained disproportionately unexplored in the Arab world, this paper reviewed several vulnerabilities and how those vulnerabilities may affect disaster and emergency management efforts in the Arab countries.

Details

Journal of Business and Socio-economic Development, vol. 1 no. 1
Type: Research Article
ISSN: 2635-1374

Keywords

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