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The main objective of the present research is to investigate the benefits of using geogrid reinforcement in minimizing the rate of deterioration of ballasted rail track geometry resting on soft clay and to explore the effect of load amplitude, load frequency, presence of geogrid layer in ballast layer and ballast layer thickness on the behavior of track system. These variables are studied both experimentally and numerically. This paper examines the effect of geogrid reinforced ballast laying on a layer of clayey soil as a subgrade layer, where a half full scale railway tests are conducted as well as a theoretical analysis is performed.

The experimental tests work consists of laboratory model tests to investigate the reduction in the compressibility and stress distribution induced in soft clay under a ballast railway reinforced by geogrid reinforcement subjected to dynamic load. Experimental model based on an approximate half scale for general rail track engineering practice is adopted in this study which is used in Iraqi railways. The investigated parameters are load amplitude, load frequency and presence of geogrid reinforcement layer. A half full-scale railway was constructed for carrying out the tests, which consists of two rails 800 mm in length with three wooden sleepers (900 mm × 90 mm × 90 mm). The ballast was overlying 500 mm thick clay layer. The tests were carried out with and without geogrid reinforcement, the tests were carried out in a well tied steel box of 1.5 m length × 1 m width × 1 m height. A series of laboratory tests were conducted to investigate the response of the ballast and the clay layers where the ballast was reinforced by a geogrid. Settlement in ballast and clay, was measured in reinforced and unreinforced ballast cases. In addition to the laboratory tests, the application of numerical analysis was made by using the finite element program PLAXIS 3D 2013.

It was concluded that the settlement increased with increasing the simulated train load amplitude, there is a sharp increase in settlement up to the cycle 500 and after that, there is a gradual increase to level out between, 2,500 and 4,500 cycles depending on the load frequency. There is a little increase in the induced settlement when the load amplitude increased from 0.5 to 1 ton, but it is higher when the load amplitude increased to 2 ton, the increase in settlement depends on the geogrid existence and the other studied parameters. Both experimental and numerical results showed the same behavior. The effect of load frequency on the settlement ratio is almost constant after 500 cycles. In general, for reinforced cases, the effect of load frequency on the settlement ratio is very small ranging between 0.5 and 2% compared with the unreinforced case.

Increasing the ballast layer thickness from 20 cm to 30 cm leads to decrease the settlement by about 50%. This ascertains the efficiency of ballast in spreading the waves induced by the track.

This study aims to predict the volume changes and collapse potential (CP) associated with the changes in soil suction by using the pressure cell and the effect of initial load on soil suction. Three types of gypseous soils have been experimented in this study, sandy gypseous soil from different parts of Iraq. A series of collapse tests were carried out using the oedometer device [single oedometer test (SOT) and double oedometer test (DOT)]. In addition, large-scale model with soil dimensions 700 × 700 × 600 mm was used to show the effect of water content changes in different relations (collapse with time, stress with time, suction with time, etc.).

A series of collapse tests were carried out using the oedometer device (SOT and DOT). In addition, a large-scale model with soil dimensions 700 × 700 × 600 mm was used to show the effect of water content changes in different relations (collapse with time, stress with time, suction with time, etc.).

The CP increases with the increasing of the void ratio for each soil. For each soil, the CP decreased when the initial degree of saturation increased. Kerbala soil with gypsum content (30%) revealed collapse value higher than Tikrit soil with gypsum content (55%) under the same initial conditions of water content and density, this is because the higher the Cu value of Kerbala soil is, the more well-graded the soil will be. Upon wetting, the smaller particles or fractions of the well-graded soil tend to fill in the existing voids, resulting in a lower void ratio as compared to the poorly graded one. Consequently, soils with high Cu value tend to collapse more than poorly graded ones. The compressibility of the soil is low when loaded under unsaturated condition, the CP for samples tested in the DOTs under stress level 800 kPa are greater than those obtained from collapse test at a stress level of 200 kPa.

The initial value of suction for all soils increases with initial water content decreases.

This paper aims to investigate how students’ attitude (SA), students’ subjective norms (SN), students’ knowledge sharing intentions (KSI) can contribute to the enhancement of knowledge sharing behaviour (KSB) among students at higher education institutes (HEI) in Oman.

This study follows the quantitative methodology and the deductive causal research approach. The data were conveniently collected through a Web-based questionnaire (Google forms) from 285 active students who are affiliated to Omani universities. SPSS was used to statistically analyse the collected data, including partial least square-structural equation modelling (PLS-SEM V3.3) to draw the results.

The study concluded that SA has both direct and indirect positive impact on SN, KSI and KSB. Moreover, the result revealed that there is a mediation effect between SA and KSB through KSI, SA and KSI when SN is playing as a mediation role.

Although this study contributes to the existing body of knowledge, this study is limited by the scarcity of the related literature in the Omani context. It is recommended that these shortfalls be addressed together while improving the knowledge-sharing behaviour among students and administrative staff. Furthermore, the potential variation between academic staff and students in terms of factors affecting their intentions to share knowledge within HEIs should be explored.

This research provides policymakers in academic fields with the appropriate approaches to leverage the knowledge-sharing behaviour amongst Omani students with the understanding of the main factors affecting individuals’ knowledge-sharing behaviours.

This will help in improving the means of employing and practising knowledge-sharing strategies within HEIs, which can generate competitive advantages amongst students and institutions while benefiting knowledge management strategies and its members.

The importance of the study stems from its context being conducted in Oman as a developing country. In addition, this study is one of the initial attempts to investigate KSB by considering SA, SN and KSI and its applicability on HEI in Oman. The findings of the study can serve as inputs to HEI in developing best practices across KSB dimensions and expanding the knowledge-sharing culture amongst HEI’s students in Oman. One of the developed strategies is the spreading of the knowledge-sharing culture among students by positively directing their attitude towards the practices of knowledge exchange.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

This study aims to measure the level of public awareness about the threat of the emerging coronavirus (COVID-19) pandemic among the Omani population. It also aims to investigate the mediating effect of the Omanis’ attitudes and behaviors with underlying conditions of COVID-19.

A cross-sectional study was conducted to collect data via an online survey of Omani citizens and residents from various geographic areas in Oman, 305 responses were received. SPSS and partial least square-structural equation modeling were used for data analysis.

The study revealed that public awareness regarding the COVID-19 pandemic was significantly influenced by people’s perceived risk, information source and health-related knowledge. Further, preventive behavior during the disease spread has a significant direct and indirect impact on their awareness. However, an insignificant mediation effect of public attitude was found between the source of information and public awareness.

This study is limited by the scarcity of related literature in the Omani context. It is recommended that future research complete an in-depth study of public awareness regarding COVID-19, using other constructs and/or other data collection techniques.

This research will provide governmental health authorities and policymakers with a guideline to establish more efficient pandemic containment strategies to control public behavior toward the COVID-19 pandemic and curb viral prevalence.

This research will help in improving prevention measures against COVID-19 are recommended to be more educated through a more effective mechanism to raise public attitude regarding pandemic prevalence positively.

The originality of this research can be drawn from key findings that indicate that people overall gained knowledge about how to deal with the COVID-19 pandemic and the accuracy of information significantly impacts public awareness.

This research explores the effect of e-learning Moodle-based system usability on students' learning outcomes with the possible intervening role of teacher's behavior and online engagement.

In this research, the authors followed a quantitative methodology and a deductive research approach. Data were collected from 433 students at different study levels and academic specializations in higher education institutions (HEIs) in Oman. The data have been analyzed using partial least squares structural equation modeling via Smart-PLS.

The findings of this research show that e-learning system usability affects students' learning outcomes. Moreover, the relationship between these two variables is mediated by teacher behavior and students' online engagement.

This study is important as it adds to the understanding of the role of e-learning system usability in predicting student outcomes. From practical perspectives, especially during the spread of the COVID-19 pandemic, this study also helps practitioners at private HEIs use e-learning systems more efficiently and effectively to improve students' engagement and learning outcomes.

Sex and age estimation is important, particularly when information about the deceased is unavailable. There are limited radiological studies investigating side, sex and age differences in normal ankle morphometric parameters. The authors’ goal was to evaluate different ankle joint morphometric measurements and document variations among Egyptians.

A prospective study was conducted throughout 23 months on 203 (100 males and 103 females) adult Egyptians, aged between 20-69 years old, who were referred for a plain x-ray of bilateral normal ankle joints.

Ankle parameters showed no statistical difference between both sides, except for tarsal width (TaW) which was significantly higher on right than left side (26.92 ± 2.66 vs 26.18 ± 2.65 mm). Males showed significantly higher morphometric values except for anteroposterior gap (APG) and talus height (TaH) which were significantly higher in females (2.29 ± 0.80 vs 1.80 ± 0.61 mm and 13.01 ± 1.68 vs 11.87 ± 1.91 mm, respectively). There was significant increase in tibial arc length, APG, distance of level of MTiTh from anterior limit of mortise, distance of level of MTiTh from vertex of mortise, sagittal distance between tibial and talar vertices and sagittal radius of trochlea tali arc in old age group compared to young one. A significant decrease in tibial width, malleolar width, TaW and TaH was noted in old age group compared to young one.

Ankle joints of both sides are mostly symmetrical; however, there are significant differences in most morphometric values due to sex and age factors. These findings may be essential during side, sex and age determination.

This paper aims to review the critical challenges and factors influencing the successful adoption of electronic learning (e-learning) systems in higher educational institutions before and during the current propagation of the coronavirus disease 2019 (COVID-19) pandemic.

This study undertook a literature review concerning the in-depth revision of previous studies published in 2020 and 2021. A total of 100 out of 170 selected research papers were adopted to identify and recognise the factors restricting the application of e-learning systems.

The findings determine and illuminate the most challenging factors that impact the successful application of online learning, particularly during the wide propagation of the COVID-19 pandemic. The review of the literature provides evidence that technological, organisational and behavioural issues constitute significant drivers that frontier the facilitation of the e-learning process in higher educational institutions.

The current paper suggests a guide for managers and scholars in educational institutions and acts as a roadmap for practitioners and academics in the educational field and policymakers as this research spotlights the significant factors challenging the e-learning process before and during the pandemic crisis.

The provided in-depth literature review in this research will support the researchers and system designers with a comprehensive review and recent studies conducted before and during the COVID-19 pandemic considering the factors limiting the e-learning process. This paper formulates a valuable contribution to the body of knowledge that will assist the stakeholders in the higher educational institutions' context.

The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-02-2022-0085.

This study aims to examine the influence of service quality (SQ) on customer loyalty (CL) and the mediating role of customer satisfaction (CS) and customer perceived value (CPV) in health insurance products in Malaysia.

Data were conveniently collected through a self-administered questionnaire from subscribers to health insurance products and services in Malaysia. A total of 456 available questionnaires were used in the analysis. Partial least square (PLS) structural equation modelling (V3.3) was used to obtain the study results.

A positive relationship is observed amongst the studied variables. In addition, CPV partially mediates the proposed relationship and also indirectly mediates the relationship between SQ and CS. Lastly, CS partially mediates the proposed relationship. Hence, all proposed direct and indirect relationships are significant and positive.

This research increases the authors’ understanding of the role of CS, SQ and CPV on CL in the health insurance industry in a developing country. The study also shows that insurance companies must establish positive relationships between insurers and customers by providing excellent SQ to maintain CS and loyalty.

This research will help managers and guide the policymakers to establish a national health financing scheme. Furthermore, these results will guide industry players on how to maintain existing and targeting customers.

This study has attempted to provide a comprehensive understanding of CL in the Malaysian health insurance industry. Considering the limited research in the Malaysian health insurance context, this study can provide theoretical contribution and a managerial basis for future studies, including implications for the managers. However, to date, research in this sector under the Malaysian context is not adequate to consider SQ, perceived values and CL factors.

This study has attempted to provide a comprehensive understanding of CL in the Malaysian health insurance industry. Considering the limited research in the Malaysian health insurance context, this study can provide theoretical contribution and a managerial basis for future studies, including implications for the managers.

Many entrepreneurs often struggle with the fear of failure, which can be detrimental to both their business and personal well-being. To better understand the factors that contribute to this fear, the authors conducted research on the impact of various obstacles, such as limited financial resources, risk aversion, stress and hard work avoidance, and prior business failures. Additionally, the authors explored the effects of social capital in mitigating these obstacles and their relationship to fear of failure in entrepreneurship.

The authors conducted a survey with 440 young Iraqi entrepreneurs using non-probabilistic and purposive methods. The survey instrument included multiple measuring scales, which were provided in both English and Arabic. The authors analysed valid responses using structural equation modelling (SEM) with partial least squares (PLS).

The findings show that the fear of failure in entrepreneurship is negatively influenced by factors such as limited financial access, risk aversion, and past business failures. However, aversion to stress and hard work did not have a significant impact. The findings also show that social capital could potentially mitigate these negative factors.

The theoretical and practical implications of this study manifest in revealing the difficulties entrepreneurs encounter in developing countries like Iraq, where entrepreneurship is vital for economic growth. The study's limitations stem from its focus on one country and the use of a single survey method. Future research could use varied methods across multiple countries for a more comprehensive view.

This study sheds light on the factors that are obstacles for entrepreneurs to starting a business in emerging economies like Iraq.