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The purpose of the paper is to introduce the dynamic phasor modelling (DPM) approach for stability investigation and control design of single-phase phase-locked loops (PLLs). The aim is to identify the system instabilities not predicted using the existent analysis and design methods based on the simplified average model approach.

This paper starts by investigating the performance of three commonly used PLL schemes: the inverse park-PLL, the second-order generalised integrators (SOGI)-frequency-locked loop and the enhanced-PLL, designed using the simplified average model and will show that following this approach, there is a mismatch between their actual and desired transient performance. A new PLL design method is then proposed based on the DPM approach that allows the development of fourth-order DPM models. The small-signal eigenvalues analysis of the fourth-order DPM models is used to determine the control gains and the stability limits.

The DPM approach is proven to be useful for single-phase PLLs stability analysis and control parameters design. It has been successfully used to design the control parameters and to predict the PLL stability limits, which have been validated via simulation and experimental tests consisting of grid voltage sag, phase jump and frequency step change.

This paper has introduced the use of DPM approach for the purpose of single-phase PLL stability analysis and control design. The approach has enabled accurate control gains design and stability limits identification of single-phase PLLs.

The purpose of this paper is to explore the specific meanings underlying the general antecedents of organisational innovativeness (OI) in one specific public sector context, to fill empirically the categories employed in prior quantitative research and to understand better some of the opportunities for strengthening facilitators of OI and overcoming barriers to OI that present themselves in particular contexts.

This research is based on a field study. It uses 29 semi-structured interviews with the members of UAE government and semi-government organisations. The research methodology is qualitative: it seeks to elucidate the meanings that structure the respondents’ understandings of innovation at work.

Across the UAE public sector there are great differences in organisational members’ interest in, and readiness to engage with, OI. Members of the public sector tended to conceptualise OI as a set of individual efforts and relationships in which the trust with superiors played a key role, as did the availability of individual rewards. For some respondents communication served as an umbrella term to denote organisational characteristics that would enable individuals to join efforts to make the public sector more innovative. Overall, the great variations in respondents’ ability to articulate and conceptualise the antecedents of OI suggests that organisational capabilities to support OI need strengthening.

The paper’s insights are based on the study of the public sector of only one country and may be difficult to generalise to other countries.

The paper suggests ways in which Emirati public sector organisations can strengthen the facilitators of OI and overcome the obstacles presented by the barriers to OI in order to help public sector leaders and employees make innovation a routine element of their day-to-day work.

The paper presents a first attempt at using qualitative research to deepen our understanding of the antecedents of organisational innovativeness in the public sector.

For education systems to meet the demands of the knowledge economy and prepare their students to be adequately skilled for a more diversified economy in the Arabian Gulf, bold and innovative initiatives must be taken in order to ensure that these skills contribute towards a sustainable knowledge economy. Gulf states have been preparing for a transition towards, what the World Bank calls ‘a knowledge economy’ (World Bank, 2013) where economies will be run by the skills and knowledge capital of their workforce with technology and its advancement playing a central role. Many governments have identified the education sector as a site in which such ambitions can be met and have therefore introduced models of education where English is the medium of instruction. The rationale behind such a decision is based on multiple reasons, mainly because English is considered by some as the language of science and discovery (see Crystal, 2003).

In all discussions surrounding the overhaul of education systems and the United Nations’ (UN) Sustainable Development Goals (SDGs) namely, goal number four (quality education), the notion of the language through which students learn is a neglected area of inquiry. English is increasingly becoming the language of instruction at the university and progressively at the school level too. This means that young students lose out on adequately learning their mother tongue. The chapter argues that only through forward, bold, and novel decisions to teach students in both Arabic and English can there be a guarantee of a more sustainable knowledge economy across the Gulf.

This paper aims to examine the factors affecting the implementation of corporate social responsibility (CSR) sustainably in mobile operators in the kingdom of Bahrain.

The research relies on the existing literature as a secondary data source. The primary data was collected through questionnaires distributed to three leading mobile operators in the Kingdom of Bahrain. The research's population numbered 1,689, and the sample size was 313; the simple random sampling method was used for data collection with a response rate of 87.2% out of a total sample size of 273 respondents. In addition, the responses were analyzed using statistical package for the social sciences (SPSS) software version 24.0; specifically, Spearman's rank correlation was used to test the hypotheses. The research design was quantitative, so a nonparametric procedure was applied to test the hypotheses.

The research produced positive relationships between the independent variables (economic, legal, ethical, philanthropic and environmental responsibilities) and the dependent variable: CSR implementation by Bahrain mobile operators; therefore, the five proposed hypotheses were accepted; furthermore, the highest positive correlation coefficient was 0.735 for environmental responsibility, and the lowest correlation coefficient was 0.533 for economic responsibility.

The research produced positive relationships between the independent variables (economic responsibility, legal responsibility, ethical responsibility, philanthropic responsibility and environmental responsibility) and the dependent variable: CSR implementation by Bahrain mobile operators; therefore, the five proposed hypotheses were accepted; furthermore, the highest positive correlation coefficient was 0.735 for environmental responsibility, and the lowest correlation coefficient was 0.533 for economic responsibility.

The outcomes of the research mainly suggest that mobile operators assign employees who have been working with the company for more than 7 years to implement CSR; due to their engagement to implement CSR as a sustainable practice more than others with less than 3 years or 3-6 years in Bahrain mobile operators. Besides, the research provides a starting point by which other researchers could investigate CSR in other sectors in the Kingdom of Bahrain.

The research provided a framework for Bahrain mobile operators to assist them in enhancing the implementation of CSR in a sustainable manner, which are economic, legal, ethical, philanthropic and environmental responsibilities.

The study aims to tackle Egypt's rising electricity consumption due to climate change and population growth, focusing on the building sector, which accounts for up to 60% of the issue, by developing new energy-efficient design guidelines for Egyptian buildings.

This study comprises six key steps. A literature review focuses on energy consumption and efficiency in buildings, monitoring a single-family building in Cairo, using Energy Plus for simulation and verification, performing multi-objective optimization, comparing energy performance between base and controlled cases, and developing a localized version of the Passive House (PH) called Energy Efficiency Design Criteria (EEDC).

The research shows that applying the (EEDC) suggested by this study can decrease energy consumption by up to 58% and decrease cooling consumption by up to 63% in residential buildings in Egypt while providing thermal comfort and reducing greenhouse gas emissions. This can benefit users, alleviate local power grid strain, contribute to Egypt's economy, and serve as a model for other countries with similar climates.

To date, no studies have focused on developing energy-efficient design standards tailored to the Egyptian climate and context using the Passive House Criteria concept. This study contributes to the field by identifying key principles, design details, and goal requirements needed to promote energy-efficient design standards for residential buildings in Egypt.

The purpose of this work is to highlight the effects of partial unipolar injection on electro-thermo-convection (ETC) in dielectric liquid contained between two eccentric cylinders.

A finite volume method was used to solve governing equations. The study is performed for different parameters, such as radius ratio (0.2 ≤ Γ ≤ 0.6), dimensionless electric Rayleigh number (0 ≤ T ≤ 900), eccentricity (−0.4 ≤ e ≤ 0.4) and thermal Rayleigh number (10 ≤ Ra ≤ 5.105).

It is found that heat transfer increases with increase in dimensionless electric Rayleigh number and eccentricity ratio.

The originality of this work is to analyze the ETC in dielectric liquid subjected to partial unipolar injection between two eccentric cylinders

This paper aims to translate and validate an Arabic version of the Barriers to Access to Care Evaluation (BACE) BACE scale to make it appropriate for the targeted socio-cultural and linguistic context.

This psychometric study has two main compounds: translating the BACE into Arabic and validating it. Using the back-translation method, the authors involved seven professional individuals to maximize the efficacy of the translated version. The authors began with the process of translating the scale from English into Arabic and vice versa followed by evaluation, compression and matching. Later, a pilot study with a sample size of 35 participants was conducted to receive feedback on the Arabic version of the scale. Finally, an online survey was generated and distributed among Arabic-speaking countries; a total of 630 participants were voluntarily involved in this study.

A total of 630 participants completed the survey with a mean age of 31.4 ± 12.9, and 402 (63.8%) were females. Cronbach’s alpha coefficient and McDonald's Omega coefficient were both greater than 0.9. The confirmatory factor analysis was found to fit highly satisfactory with the stigma-related barriers.

The BACE was validated in Arabic and its psychometric properties were examined in-depth and found to be strong.

This paper fulfils an identified need to translate tools to make mental health more accessible to patients in need.

The purpose of this paper is to give insight on the important preparation task needed to be considered by prospective PhD candidates prior to the start of their study. As pursuing and obtaining a higher degree qualification is becoming more eminent for those who want to advance their academic career, crucial preparation is needed before embarking on the doctoral quest.

A small-scale study of the PhD experience was carried out in a public university in Malaysia using semi-structured in-depth interviews with eight successful doctoral students representing three different faculties to assess respondents’ experiences concerning the preparation aspect, challenges faced and strategies used to overcome the problem.

From the interview data, three overarching themes emerged: motives, task and financial and health as important dominators that could influence a successful venture of a PhD journey.

As the present research respondents were few, further research with bigger number of respondents may shed better light in identifying other important aspect in preparation for PhD. The authors are unable, in the space of this paper, to fully explore the implications of the data, and the work of others that it builds on, for the future of professional doctorates or other types of PhD awards. As professional doctorates are fully concentrated on their professional endeavour, i.e. nursing and education, the preparation needed may include different groundwork. In addition, this study was carried out in Malaysia, where the system may not necessarily share the same characteristics to other doctoral systems in other countries. Cultural differences, the impact of age, gender and race, were other variables that could be weighed by future research in the same area.

The university’s graduate office should line-up courses to inform future doctoral candidates on the aspect of preparation at personal level that the students need to carry out.

The study provides new views where potential doctoral students should be helped and guided to become more consciously aware of their decision in pursuing a higher degree. This paper provides suggestions on the guidelines of the initial preparation needed before embarking on a PhD journey and managing their own learning.

The paper establishes the important aspect of the preparation phase needed to be considered by future doctoral students before pursuing their doctoral quest.

The purpose of this paper is to investigate the impact of thermal radiation interaction with Hall current, buoyancy force, and oscillatory surface temperature on hydromagnetic-mixed convective heat exchange stream of an electrically conducting nanofluid past a moving permeable plate in a porous medium within a rotating system.

Analytical closed-form solutions are obtained for both the momentum and the energy equations using the perturbation method.

The effects of various important parameters on velocity and temperature fields within the boundary layer are discussed for three different water-based nanofluids containing copper (Cu), aluminum oxide (Al₂O₃), and titanium dioxide (TiO₂) as nanoparticles. Local skin friction and Nusselt number are illustrated graphically and discussed quantitatively. The results show that Hall current significantly affects the flow system. Results for some special cases of the present analysis are in good agreement with the existing literature.

The problem is relatively original to study the hydromagnetic-oscillatory flow of a nanofluid with Hall effect and thermal radiation past a vertical plate in a rotating porous medium.