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The retention and success of engineering undergraduates are increasing concern for higher-education institutions. The study of success determinants are initial steps in any remedial initiative targeted to enhance student success and prevent any immature withdrawals. This study provides a comprehensive approach toward the prediction of student academic performance through the lens of the knowledge, attitudes and behavioral skills (KAB) model. The purpose of this paper is to aim to improve the modeling accuracy of students’ performance by introducing two methodologies based on variable selection and dimensionality reduction.

The performance of the proposed methodologies was evaluated using a real data set of ten critical-to-success factors on both attitude and skill-related behaviors of 320 first-year students. The study used two models. In the first model, exploratory factor analysis is used. The second model uses regression model selection. Ridge regression is used as a second step in each model. The efficiency of each model is discussed in the Results section of this paper.

The two methods were powerful in providing small mean-squared errors and hence, in improving the prediction of student performance. The results show that the quality of both methods is sensitive to the size of the reduced model and to the magnitude of the penalization parameter.

First, the survey could have been conducted in two parts; students needed more time than expected to complete it. Second, if the study is to be carried out for second-year students, grades of general engineering courses can be included in the model for better estimation of students’ grade point averages. Third, the study only applies to first-year and second-year students because factors covered are those that are essential for students’ survival through the first few years of study.

The study proposes that vulnerable students could be identified as early as possible in the academic year. These students could be encouraged to engage more in their learning process. Carrying out such measurement at the beginning of the college year can provide professional and college administration with valuable insight on students perception of their own skills and attitudes toward engineering.

This study employs the KAB model as a comprehensive approach to the study of success predictors. The implementation of two new methodologies to improve the prediction accuracy of student success.

The purpose of this study is to compare the inhibitive effect of polyaniline (PAni) and N-cetyl-N,N,N trimethyl ammonium bromide (CTAB)-stabilized PAni in a hydrochloric acid (HCl) medium.

PAni has been deposited potentiodynamically on mild steel in the presence of CTAB as a stabilizing agent to achieve high corrosion inhibition performance by the polymer deposition. The corrosion inhibition studies of CTAB-stabilized PAni inhibitor in 0.1 M HCl acidic solution was carried out by electrochemical methods, namely, open-circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy technique.

The results of electrochemical studies have shown that the CTAB-stabilized PAni inhibitor has higher corrosion efficiency than PAni on mild steel in 0.1 M HCl solution. The maximum per cent efficiency evaluated using the potentiodynamic polarization method is approximately 91.9.

CTAB-stabilized PAni has never been studied as a corrosion inhibitor for mild steel in an acidic medium. The investigations demonstrate relatively the better corrosion inhibition efficiency and high dispersion of the polymer in the acidic medium.

This study aims to assess the awareness about the rights of people with mental illness in the main psychiatric hospital in Tunisia among the service users, the family members and the staff.

The Convention of Rights of People with Disabilities mandates that State Parties initiate and maintain campaigns and human rights training to promote understanding of the rights of people with mental illnesses, considered as a main factor for their fulfillment. Service users, family members and staff evaluated, through a survey, the importance of ten rights for persons with mental illness, stated in the convention.

Disparities were found in the perception of the different rights by and between the three groups. The highest levels of awareness were associated with the freedom from torture or degrading treatment and the right to live with dignity and respect, whereas the lower importance were assigned to the right to participation in recovery plans, to give consent and to exercise legal capacity.

The lack of awareness and the poor perception of rights of people with mental illness is one of the barriers to their achievement. More training and awareness raising is necessary.

The purpose of this paper is to propose a new hybrid control method of pulse width modulation (PWM) active rectifiers tied to the grid through an LCL filter. The control method is designed with the aim to achieve a perfect regulation of the dc-bus voltage; a near unity input power factor (UIPF) operation as well as a high quality of the line currents.

The proposed hybrid control method consists of a PI-based linear controller cascaded with a nonlinear one. The nonlinear controller (inner loop) is designed using the input-output feedback linearization (IOFL) theory. It should control both the dc-bus voltage and the input currents at the converter’s poles. The linear controller (outer loop) is devoted to control the reactive line current so as to achieve a near UIPF.

A perfect regulation of the dc-bus voltage and a near UIPF operation are achieved. Moreover, a high quality of the line currents is obtained. The robustness and effectiveness of the proposed control method have been successfully tested under variation of the dc voltage reference as well as grid and load disturbances.

The proposed method is useful for single-stage and two-stage grid connected photovoltaic systems, wind energy conversion, and distributed power generation systems.

The main novelty of this paper is the combination of linear and nonlinear controllers with the aim to control a PWM active rectifier tied to the grid through a third-order LCL filter. In the opinion, such control method has not been applied to this converter in earlier research papers. The numerical simulations carried out under normal and abnormal conditions confirm the effectiveness of the proposed approach.

Transformative service research (TSR) has received considerable attention from researchers and marketers in recent years and becomes a research priority in health care. In response, this paper adapts the TSR entities and wellbeing framework to systematically review healthcare quality research on Muslim consumers. The purpose of this paper is to identify research gaps and provide directions for future research, aligning healthcare studies with the TSR framework.

The authors of this paper reviewed empirical papers in healthcare quality research on Muslim patients between the years 2000 and 2020. The recorded journal articles were synthesized using insights from the TSR framework. Several literature gaps were identified and future research directions were provided using the TCCM framework, in which T stands for theory, C for context, C for characteristics and M for methodology.

This paper finds studies that encompass several domains of the TSR framework including cultural and religious dimensions, service interaction and customer engagement dimensions and customer service wellbeing. Findings also reveal subject matters related to the TSR framework, which receive less attention in the healthcare literature. A number of potential avenues for theoretical extension in health care are also discussed.

The implications of this paper are highly relevant to Muslim healthcare consumers, the healthcare system and society in general. The findings suggest inspiring changes in the healthcare ecosystem that yields a greater quality of life (health and wellbeing) for individuals and their respective communities.

This paper advances the current state of healthcare research by identifying and organizing components of TSR entities and wellbeing framework, using Muslim patients as the context. It enhances some pioneering approaches within the domain of TSR and quality dynamics and provides a holistic perspective as guidance and systematic thinking to further advancement in the field of services marketing and Islamic marketing.

Expert systems are computer-based systems that mimic the logical processes of human experts or organizations to give advice in a specific domain of knowledge. Fuzzy expert systems use fuzzy logic to handle uncertainties generated by imprecise, incomplete and/or vague information. The purpose of this paper is to present a comprehensive review of the methods and applications in fuzzy expert systems.

The authors have carefully reviewed 281 journal publications and 149 conference proceedings published over the past 37 years since 1982. The authors grouped the journal publications and conference proceedings separately accordingly to the methods, application domains, tools and inference systems.

The authors have synthesized the findings and proposed useful suggestions for future research directions. The authors show that the most common use of fuzzy expert systems is in the medical field.

Fuzzy logic can be used to manage uncertainty in expert systems and solve problems that cannot be solved effectively with conventional methods. In this study, the authors present a comprehensive review of the methods and applications in fuzzy expert systems which could be useful for practicing managers developing expert systems under uncertainty.

The purpose of this paper is to investigate steady state creep behavior of a functionally graded rotating disc under varying thermal gradient (TG).

The steady state creep in a rotating FGM disc with linearly varying thickness has been investigated by using von-Mises yield criterion. The disc under investigation is assumed to be made of FGM containing non-linear distribution of silicon carbide particle (SiC_p) in a matrix of pure aluminum along the radial distance. The creep behavior of the FGM composite disc is described by threshold stress-based law. The stresses and strain rates in the FGM disc have been estimated for different kinds of TG.

The results indicate that when the FGM disc is subjected to a radial TG, with temperature increasing with increasing radius, the radial stress in the disc increases over the entire disc but the tangential and effective stresses increase near the inner radius and decrease toward the outer radius. The imposition of such a radial TG in the FGM disc leads to significant reduction in the radial and tangential strain rates. With the increase in magnitude of TG in the FGM disc, the inhomogeneity in creep stresses increases but the inhomogeneity in strain rates decreases significantly, thereby reducing the chances of distortion in the FGM disc.

The creep strain rates in rotating FGM disc could be significantly reduced when the disc is subjected to a radial TG, with temperature increasing with increasing radius.

The purpose of this paper is to present an organized review of existing research on reconfigurable manufacturing system (RMS). The paper considers majority of the prominent research articles in the domain of RMS published ever since RMS was envisaged in 1997.

The paper systematically reviews, classifies and analyses the published literature on postulations and design of RMSs. The general observations from the literature and research gaps recognized thereon are highlighted at the end of each section/sub-section.

The paper reveals important aspects related to RMS research since its inception. It also recognizes the areas of RMS research requiring more focus. The study also highlights open issues and future directions for further research.

The literature in the domain of RMS has so far been narrow. This paper reviews the prominent research in this field and presents an overview of its conceptual developments and various mathematical models for the RMS design and its optimization so far developed by the researchers. Further, manufacturing advancements and future directions have also been proposed for the efficient execution of RMS paradigm in manufacturing industries.

The paper provides an organized listing of published research work in the field of RMS. This work will provide an insight to the researchers, practitioners and others related directly or indirectly to this field to develop and understand better strategies for supervising and controlling the smooth implementation of RMS.

Functionally graded materials are a special class of composites in which material are graded either continuously or layered wise depending upon its applications. With such variations of materials, the properties of structure vary either lengthwise or thickness wise. This paper aims to investigate models for effective estimation of material properties, as it is necessary for industries to identify the properties of composites or functionally graded materials (FGM’s) before manufacturing and also to develop novel material combinations.

Available models were compared for different material combinations and tested with experimental data for properties such as Young’s modulus, density, coefficient of thermal expansion (CTE) and thermal conductivity. Combinations of metal–ceramic and metal–metal were selected such that their ratios cover a wide range of materials.

This study reveals different models will be required depending on the material used and properties to be identified.

The results of the present work will help researchers in the effective modeling of composites or FGM’s for any analysis.

This paper presents a comparison and review of various analytical methods with experimental data graphically to find out the best suitable method. For the first time, the Halpin-Tsai model was extended in the analysis of the CTE which shows good approximations.