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This study aims to validate a proposed conceptual model for the implementation of sustainable institutional repositories (IRs) in Nigeria.

A quantitative approach shaped the survey research design. This study used structural equation modeling (SEM) analysis to evaluate the proposed model. The population of the study comprises 117 librarians, information technology staff and researchers knowledgeable about IR implementation status across 14 public universities in Nigeria. The data was collected using an online survey. The Smart-PLS v3.3 software was used to facilitate the analysis.

The findings indicate that the nine identified factors of the IR sustainability model have a significant influence on the implementation of sustainable IRs. This signified that the model has adequately depicted the relationship between the implementation of sustainable IRs and the identified factors.

This study provides an integrated synthesis of factors that influence the implementation of sustainable IRs. This study also presents the first-ever empirically validated model for sustainable IRs. The findings of this study addressed the challenge of implementing sustainable IRs and institutionalized the idea of IRs’ sustainability assessment.

The study aims to explore the mediating role of organizational culture in the relationship between on-the-job training (OJT), induction training and employee job performance. This study is conceptually grounded in Albert Bandura’s Social Cognitive Theory. The function that organizational culture plays as a mediator in the links between employee performance and on-the-job training and induction is a unique aspect of this study.

An industry-wide representation was ensured in the study by using a stratified random sampling technique to choose participants. The main characteristics pertaining to organizational culture, training initiatives and worker job performance were measured by using validated scales from earlier studies. For the purpose of validating the measurement model, factor loadings, internal consistency reliability and discriminant validity were evaluated through the use of partial least squares structural equation modelling in SmartPLS.

In support of Bandura’s Social Cognitive Theory, the study’s results show a strong association between work performance, organizational culture, on-the-job training and induction training. The study highlights the positive synergistic effect that supportive organizational culture and well-designed training programmes have on improving employee job performance. The unique contribution of this study is the provision of empirical support for these correlations across a wide range of industries, highlighting the crucial roles that organizational culture plays in promoting employee success.

Authors’ knowledge of how organizations may create environments that maximize worker productivity and potential is expanded by the study’s practical insights.

The purpose of this paper is to describe a new method for sensorless hysteresis direct torque control (HDTC) algorithm for permanent magnet synchronous motor to minimize torque ripple and electromagnetic interference (EMI) noises.

The design methodology is based on space vector modulation of electrical machines with digital vector control. MATLAB simulations supported with experimental study under C++ are used.

The simulation and experimental results of this proposed algorithm show adequate dynamic torque performance and considerable torque ripples reduction as well as lower current ripples, lower EMI noise level as compared to traditional HDTC.

This research is limited to PMSM, however the research can be extended to include induction motor as well. In addition, the actual mathematical relation between the torque ripple and flux ripple can be studied to set the flux and torque bands width in reasonable value, and this relationship can be used to select switching time of the active selected vectors.

The implementation of the proposed algorithm in microcontroller embedded systems is described. It requires no PI controller in the torque control loop In addition, based on existence direct torque control equipment, it is only required to change the software switching algorithm, to provide smooth torque, given that the switching frequency of the inverter module is more than or equal to 15 kHz and the system is supplied with timers.

The algorithm used in this work utilizes the output of two hysteresis controllers used in the traditional HDTC to determine two adjacent switching vectors per one sample time. The algorithm also uses the magnitude of the torque error, magnitude of the flux error and stator flux position to select the switching time for the selected vectors to control the applied average voltage level in such a way that the torque ripple is minimized. The selection of the switching time of the selected active vectors utilizes novel table structure which reduces the complexity of calculation. This work is directed to designers of ac motor drive system who seek smooth torque performance as well as low EMI noise level.

The paper seeks to provide an adaptive fuzzy logic controller for permanent magnet synchronous motor (PMSM) under direct torque control (DTC) algorithm to minimize the torque ripple.

The design methodology is based on vector control analysis. MATLAB simulations supported with experimental study under C++ are used to execute the proposed work.

The results show that considerable torque ripple reduction as well as considerable current ripple reduction can be achieved by utilizing adaptive fuzzy switching algorithm to fire the inverter supplying the PMSM.

This research is limited to PMSM, however the research can be extended to include other AC motors as well. In addition, the following points can be studied, the effects of harmonics in control signals on the torque ripple. Digital and active filters as solution to these harmonics can be also addressed. The actual mathematical relation between the torque ripple and flux ripple can be studied to set the flux and torque bands width in reasonable value.

Based on existence DTC control system, it is only required to change the software‐switching algorithm, to provide smooth torque, given that the switching frequency of the inverter module is more than or equal to 15 kHz and the system is supplied with timers. In addition, a relatively higher DC voltage may be required to achieve higher speed compared with the traditional DTC.

In this paper, the stator flux position, and errors due to deviations from reference values of the torque and stator flux are used to select two active vectors while at the same time the absolute value of the torque error and the stator flux position are fuzzified to adapt the switching of the inverter in order to control the applied average voltage level in such a way as to minimize the torque ripple, so instead of fixed time table structure, a fuzzy logic is used to calculate the switching time for the selected vectors and no PI controller is used as the case in the traditional‐space vector modulation. This work is directed to motor drive system designers who seek highly smooth torque performance with fast response.

The purpose of this paper is to present modelling of power losses dependences on temperature in soft magnetic materials exposed to non-sinusoidal flux waveforms and DC bias condition.

Scaling theory allows the power loss density to be derived in the form of a general homogeneous function, which depends on the peak-to-peak of the magnetic inductance ΔB, frequency f, DC bias HDC and temperature T. The form of this function has been generated through the Maclaurin expansion with respect to scaled frequency, which suit very much for the Bertotti decomposition. The parameters of the model consist of expansion coefficients, scaling exponents, parameters of DC bias mapping, parameters of temperature factor and tuning exponents. Values of these model parameters were estimated on the basis of measured data of total power density losses.

The main finding of the paper is a unified methodology for the derivation of a mathematical model which satisfactorily describes the total power density losses versus ΔB, f, H_DC, and T in soft magnetic devices.

Still the derived method does not describe dependences of the power density loss on shape and size of considered sample.

The most important achievement is of the practical use. The paper is useful for device designers.

This paper presents the algorithm which enables us to calculate core losses while the temperature is changing. Moreover, this method is effective regardless of soft magnetic material type and the flux waveforms as well as the DC bias condition. The application of scaling theory in the description of energy losses in soft magnetic materials justifies that soft magnetic materials are scaling invariant systems.

Patient safety focuses on minimizing risks that might occur to patients during provision of healthcare. The purpose of this study was to explore healthcare practitioners’ attitudes towards patient safety inside different hospital settings in Jeddah, Kingdom of Saudi Arabia.

A descriptive, cross-sectional study was conducted on a sample of healthcare practitioners in main hospitals in Jeddah. Two main hospitals (one governmental and one private) were selected from each region of Jeddah (east, west, north and south), with a total number of eight out of thirty hospitals. Data were collected through the Attitudes to Patient Safety Questionnaire III that was distributed online. The questionnaire used a 5-point scale. Descriptive statistics were used. Comparisons were made by independent t-test and ANOVA. The statistical significance level was set at p < 0.05.

The study included 341 healthcare practitioners of different sexes and specialties in eight major governmental and private hospitals in Jeddah. “Working hours as error cause” subscale had the highest mean score (4.03 ± 0.89), while “Professional incompetence as error cause” had the lowest mean score (3.49 ± 0.97). The total questionnaire had a moderate average score (3.74 ± 0.63). Weak correlations between the average score of the questionnaire and sex, occupation and workplace were found (−0.119, −0.018 and −0.088, respectively).

Hospitals need to develop targeted interventions, including continuing professional development programs, to enhance patient safety culture and practices. Moreover, patient safety training is required at the undergraduate education level, which necessitates health professions education institutions to give more attention to patient safety education in their curricula.

The study contributed to the existing literature on patient safety culture in hospital settings in Jeddah, Saudi Arabia. The insights generated by the study can inform targeted interventions to enhance patient safety culture in hospitals and improve patient outcomes.

The purpose of this paper is to develop the Permanent Magnet Synchronous Motors drive which has possibility to work in sensorless mode at low speed based on back EMFs estimation.

Estimation uses modified Luenberger observer and the preprocessing of the EMFs before calculating the speed, using derivative and the Kalman filter (KF) to obtain smooth waveform of the estimated speed. This modification is needed because of the nonlinear change of the estimated back EMFs amplitude as a function of speed, in low-speed range.

How to use back EMF observer to estimate a speed in the low-speed range was found in the course of the work. Simple and effective algorithm uses KF and can work even with a relatively big deformation of the estimated back EMF.

Such sensorless drive may be used in low-cost constant or variable speed drive in domestic use or industrial application. Such drive may work properly where there is no initial load torque and the sign of the speed does not change.

Presented results challenge the view that at low-speed range (not the standstill), the back EMF-based method of position estimation is very difficult or impossible. However, the problem lays in proper speed estimation, not the position estimation.

This study aims to develop a performance evaluation model for Facebook (FB) marketing campaigns (FBMCs) for a franchised hotel, distinguish four quadrants based on efficiency and customer attention and suggest improvements for inefficient FBMCs based on the slack value analysis.

The paper applied the elaboration likelihood model to select three inputs (text, picture and color) and three outputs (number of people reached; reactions, comments and shares; and clicks on post) based on the literature and expert opinions to assess 60 FBMCs for hotels through data envelopment analysis and a robustness test. The four-quadrant analysis (benchmark, improvements in efficiency and customer attention and fade-out) provides suggestions for underperforming FBMCs.

The results indicate that the efficiency of the greeting FBMCs is better than that of the event and promotion FBMCs. The projection of input value analysis showed that an average of 50 words, one picture and six colors is the benchmark of FBMCs.

Sixty FBMCs for the same franchised hotel were examined. Further research could extend this model to different hotels for generalization.

The findings suggest that developing shorter text lengths, concise photos and colors of greeting messages on FB could be efficient for FBMCs.

This paper contributes in assessing the performance of FBMCs to identify the benchmark FBMCs with the higher efficiency and more customer attention for a franchised hotel.

The Sexton et al.’s (2006) safety attitudes questionnaire (SAQ) has been widely used to assess staff’s attitudes towards patient safety in healthcare organizations. However, to date there have been few studies that discuss the perceptions of patient safety both from hospital staff and upper management. The purpose of this paper is to improve and to develop better strategies regarding patient safety in healthcare organizations.

The Chinese version of SAQ based on the Taiwan Joint Commission on Hospital Accreditation is used to evaluate the perceptions of hospital staff. The current study then lies in applying importance-performance analysis technique to identify the major strengths and weaknesses of the safety culture.

The results show that teamwork climate, safety climate, job satisfaction, stress recognition and working conditions are major strengths and should be maintained in order to provide a better patient safety culture. On the contrary, perceptions of management and hospital handoffs and transitions are important weaknesses and should be improved immediately.

The research is restricted in generalizability. The assessment of hospital staff in patient safety culture is physicians and registered nurses. It would be interesting to further evaluate other staff’s (e.g. technicians, pharmacists and others) opinions regarding patient safety culture in the hospital.

Few studies have clearly evaluated the perceptions of healthcare organization management regarding patient safety culture. Healthcare managers enable to take more effective actions to improve the level of patient safety by investigating key characteristics (either strengths or weaknesses) that healthcare organizations should focus on.

Continuous integration of health screens to investigate and track variations in the students’ healthiness over time is essential. However, the sustainability of this practice remains challenging. The purpose of this paper is to identify the prevalence of anaemia based on haemoglobin (Hb) estimation among Saudi school girls in Jeddah city by examining capillary and venous blood.

The design is investigative, using primary data to define the prevalence of anaemia based on two techniques. Samples of venous (n=408) and capillary (n=797) blood from Saudi school girls in Jeddah city was collected and compared using: Reflotron Plus System method (capillary blood) and ABX MICROS 60-OT Automated Haematology Analyser for (venous blood).

When the capillary blood was used, the prevalence of anaemia was 40 per cent (n=319 out of 797). Using the venous blood, the prevalence was 29.4 per cent (n=120 out of 408). Comparison of Hb data for both tests showed a significant difference in Hb levels with levels between the 10g and 12 g/dl particularly and both measurements demonstrated good agreement (ICC=0.87, 95 per cent CI (0.845, 0.892)).

The data were collected only in Jeddah city. Further studies should include a national sample that is representative of both gender from different backgrounds and geographical areas in the kingdom of Saudi Arabia.

The high prevalence of anaemia within the school girls’ population require decision makers to devise a set of maintainable projects to progress students’ general health, including health education and supplementation such as iron, particularly if anaemia is diagnosed to be nutrition-related. This particularly applied to the health centres at female schools that have anaemia screening programmes that going on in Saudi schools.

This study reveals a technique-based measures of anaemia prevalence that have public and practical health implications.