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Background: With the dramatic rapid increase in population growth and in the use of the automobile in the world, especially in developing countries such as Jordan, related traffic problems have become more and more complex. Parking is one of the major problems that are created by increasing road traffic. Both on-street parking and pedestrian crossing are important components of the urban transport system. On-street parking is an important component of the parking system. Because of its occupancy of roadway resources, it can significantly impact traffic performance and safety. The lack of providing an adequate number of parking areas within urban central business districts (CBDs) and the lack of off-street facilities in urban neighborhood commercial areas, both result in increased on-street parking and disturbance of traffic stream. The management of on-street parking is one of the main parameters in traffic management. In developing countries, as the number of vehicles and parking demand had increased significantly in recent years, on-street parking-related concerns are no longer confined to the city center; they extend throughout the whole urban region. Furthermore, the correlation between on-street parking and traffic safety is still a controversial issue. The research findings of this study help to develop a better understanding of both on-street parking and pedestrian crossing at mid-block location and help to plan and design proper transportation facilities on urban streets. The model of this study can give quantitative results regarding the influence of on-street parking on through traffic operations. Findings of the study can support municipal engineering (policy decisions) for on-street parking hour permits. As delay on the street segment and road network can be calculated, municipal engineering (policy makers) can set up a maximum tolerable threshold in the delay profile to decide when street parking is permitted on which network path for how many vehicles. A time varying parking fee policy can be proposed according to actual delay caused by the parked vehicles at the entire network or the like. Many engineers are concerned about the increase in the number of accidents which are associated with on-street parking. In addition to the above-mentioned issues concerning the relationship of on street parking with through traffic movements, the pedestrian is one of the important components in urban transportation system and is vulnerable at unprotected mid-block locations under high traffic conditions. At unprotected mid-block locations, some vehicles may yield to pedestrians who are already at crosswalk location. Moreover, because of poor construction of separated facilities and road side development especially in developing countries, pedestrians usually cross the road at unprotected mid-block locations under high traffic conditions. Furthermore, the use of most major streets in developing countries such as Jordan are not properly monitored and managed especially with regards to on-street parking and pedestrian crossing, and therefore reducing the capacity of roadways and probably causing accidents. This research could provide insights for transportation agencies as it is related to traffic operations issues and safety especially in developing countries. Objective: 1. Investigate the effect of on-street parking on through traffic in terms of delay. 2. Develop a model that can estimate the effect of on-street parking on through traffic. 3. Investigate the effect of pedestrian crossing on travel time. Method: Data was collected using a video camera for a total of 37 street segments from three major cities in Jordan, during off-peak hour and dummy regression was used for analysis. Result and Discussion: Results revealed that on-street parking maneuvers (in/out) and pedestrian forced gap can significantly influence through traffic characteristics of Jordan traffic network. The trend of traffic volume was found to fall gradually, while average delay time was found to rise gradually with an increase in the number of parking maneuvers (in/out). The average percent reduction in maximum traffic volume at one lane was 28.7% which was more than that at two lanes (18.6%) under high parking maneuver conditions. The average delay time caused by heavy vehicles, angle parking, street without median, and street in a central business district (CBD) commercial area was more than that caused by the presence of passenger vehicles, parallel parking, street with median, and street in non-CBD commercial area by 27.8%, 31.7%, 29.7%, and 10.0%, respectively. The vehicular speeds had a significant drop reaching a value of 32.0% on average with pedestrian crossing when compared to no pedestrian crossing at mid-block location. A prediction model using dummy regression was proposed and shown to be able to predict average delay time. Conclusion: 1. On-street parking maneuvers can significantly influence the maximum traffic volume of street segments in Jordan. 2. A trend for traffic volume to fall gradually with an increase in the number of parking maneuver (in/out) was concluded. 3. The average percent reduction in maximum traffic volume at one lane (28.7%) was more than that at two lanes (18.6%) where there is high parking maneuver. Of all the factors that can impede the flow of traffic on the roadway, on-street parking can be considered the most important factor. The reduction of roadway width by the owners of shops who sometimes occupy one lane of the roads also affects the traffic operation and reduces traffic volume. 4. A trend for average delay time to rise gradually with an increase in the number of parking maneuver (in/out) was concluded. 5. The average delay time caused by heavy vehicles, angle parking, street without median and street in CBD commercial areas was more than that caused by the presence of passenger vehicles, parallel parking, street with median and street in non-CBD commercial by 27.8%, 31.7%, 29.7%, and 10.0%, respectively. Also, on-street parking maneuvers may be a contributory factor to causing temporary bottlenecks in moving traffic, which may result in causing more operational problems such as congestion and accidents. 6. The vehicular speeds were implicitly affected by pedestrian crossing when compared to no pedestrian crossing location. In other words, there was a significant drop of speed value reaching an average of 32.0%. 7. Compared with the effects of all the independent variables, number of parking maneuvers has the greatest influence on the estimated average delay time. 8. Prediction models using dummy regression were proposed and shown to be able to predict average delay time if provided inputs are within the data range used in developing the models.

Rutting, fatigue cracking and low temperature cracking are the most important distresses in asphalt pavements as a result of changes in rheological properties of asphalt binder. Many types of modifiers were used to enhance asphalt behavior at both low and high temperatures. In this study, carbon nanotubes (CNT) were used as one of many nanomaterials that take a large attention in the latest research related to asphalt modification against different types of distresses. Effect of CNT on rheological properties of asphalt binder was investigated by testing unmodified and CNT modified asphalt binders using two of Superpave devices: Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR). Penetration, softening point, flash point and rotational viscosity (RV) tests were carried out as well. CNT was added in 0.1%, 0.5% and 1% by weight of asphalt binder. It was found that adding CNT in 0.5% and 1% increase stiffness of asphalt and consequently asphalt pavement rutting resistance. On the other hand, this increase in stiffness affected pavement behavior adversely which is not desirable for fatigue and low temperature cracking. However, Superpave specifications were still satisfied and asphalt binder’s relaxation properties were improved upon CNT modification. It was eventually found that 0.5% of CNT is the optimum percentage for the best performance.

Purpose The purpose of this study is to investigate the factors that affect students’ behavioral intentions to use virtual classrooms at Princess Sumaya University for Technology (PSUT) in Jordan. Design/methodology/approach A quantitative research approach was adopted, an online survey method was used and the data were collected among students at PSUT in Jordan. A total of 511 responses were usable for analysis. A structural equation modeling partial least squares technique was used to examine the hypothesized model. Findings The findings reveal that the proposed factors have direct and indirect relationships with behavioral intentions to use virtual classrooms. They show that students’ satisfaction has a direct influence on behavioral intention, while other variables such as instructor characteristics, virtual classroom quality, perceived self-efficacy, perceived organizational support, perceived ease of use and perceived usefulness have an indirect effect on behavioral intentions to use virtual classrooms. Research limitations/implications The study was conducted at PSUT in Jordan, which could limit the generalizability of the findings. Furthermore, the present study measured students’ behavioral intentions to use virtual classrooms and future research should consider the actual use of virtual classrooms. Practical implications The findings of this study offer significant and useful information to policymakers, instructors, developers and students regarding the use of virtual classrooms in universities. Based on students’ needs and readiness, the findings identify which factors to consider when developing an e-learning system to enhance learning and teaching performance. Originality/value This study extends existing knowledge by developing a conceptual model to identify the key factors of virtual classroom adoption in higher education institutions in Arab countries. This study contributes to the literature in the context of e-learning by validating an extended technology acceptance model from an Arab countries perspective and considering the differences in culture, learning style and physical environment compared to developed countries.

The paper aims to find whether friction values namely skid numbers obtained by the Locked Wheel Skid Trailer (LWST) device can be predicted using values obtained by the Dynamic Friction Tester (DFT) and the Circular Texture Meter (CTM). The last two measure the coefficient of dynamic friction (called DFTx) at different speeds (labeled x) and the Mean Profile Depth (MPD), they also measure the International Friction Index (IFI) parameters F60 and Sp. Artificial Neural Network (ANN) software was used to investigate the relationships. Twelve (12) different models were proposed with different input parameters and the best model giving the highest coefficient of determination (R2) was discussed in this paper. The results show that the most influential factors on LWST friction values are MPD, DFT0, DFT50, and DFT64 and MPD was the strongest among them. In addition, results show that the ANN approach is very efficient in predicting the LWST friction values for both training and validation sets with R2 values of 79% and 83%, respectively. It was also shown that the IFI parameters were relatively less influential on LWST values than DFT and MPD measurements.

The aim of this study is to identify improvements in the physical and rheological properties of asphalt binders when alumina microfibers are added in the role of modifiers. Modified asphalt binder composites were prepared using three different alumina microfiber percentages (0.05, 0.1 and 0.2%) by volume on PG70-10 standard asphalt binder grade. The performance properties of the materials were evaluated against standard performance measurements such as penetration, ductility, flash, fire and softening points along with Superpave test protocol. The results of the investigation demonstrated that the use of improved characterization methods is advantageous in assessing modified asphalt binder performance. One such method used is Scanning Electron Microscopy (SEM) imaging. Other methods that would help better characterize cracking and rutting resistance included the following: Multiple Stress Creep Recovery (MSCR) test, Glover-Rowe (G-R) parameter and delta Tc (∆Tc) parameter. The results of the MSCR test clarified the inconsistencies between the physical and rheological properties. The percent recovery (R) and the non-recoverable creep compliance (Jnr) changes with the addition of alumina microfiber caused an improvement in the asphalt binder’s rutting resistance while maintaining an acceptable fatigue cracking performance. Based on ΔTc and G-R parameters, it was found that the incorporation of alumina microfiber increased the asphalt binder’s ability to withstand additional aging without showing signs of cracking. As per fatigue cracking and thermal cracking routines, the optimum content of alumina microfiber was determined to be 0.1% for best performance against cracking as well as rutting. In addition, it was revealed statistically that alumina microfiber had a meaningful capability to improve physical and rheological properties of asphalt binders.

Bonding strength between asphalt and aggregate is considered an important feature that governs the future performance of flexible pavements. This study investigated five factors that have the poten...

The objective of this research is to contribute to the understanding of the online community by empirically examining the major factors motivating online community members to participate and actively contribute to their communities. In pursuing this endeavor, a comprehensive conceptual model of motivations that drive online community participation is developed based on an extensive revision of the existing relevant literature. However, modest research had been conducted to understand the online participant's motivation to participate in online communities. Thus, the current research model will enhance understanding and add to the relevant existing knowledge by categorizing digital user's motivation to participate in online communities, through the employment of Maslow's hierarchy of needs theory and Herzberg's two-factor theory. The paper used a deductive methodological approach adopted.

The COVID-19 pandemic has caused major disruptions in every sector of human activity around the world. The education sector is no exception. Due to physical restrictions in accessing campus infrastructures, students and instructors at academic institutions have forcibly adapted to the new norm of virtual learning with mixed expectations and outcomes. There have been several studies conducted by educational practitioners since the pandemic began, which mostly focused on how academic constituents quickly adapt to virtual learning in a general sense. The main objective of this study is to examine the effects of virtual learning infrastructure and environment on student learning, specific to the civil engineering program at Prince Mohammad Bin Fahd University (PMU). A survey was distributed to civil engineering students at PMU at the end of the fall 2020 term to gather perceptions about virtual learning and check the adequacy of online learning tools and associated environments. Student performance during virtual learning in terms of grade achievement was also investigated and compared with a normal situation. In general, it was found that students are satisfied with the current technology used to facilitate virtual learning. The anticipated outcomes of this study, including online technology readiness, curriculum adjustment, and teaching styles or methods, are to be used for virtual learning improvement should the current pandemic restriction extend to the end of the 2020–21 academic year and possibly far beyond. © 2021, International Journal of Information and Education Technology. All rights reserved.

There are various models for predicting the friction or skid number of asphalt pavements based on inputs such as aggregate characteristics, aggregate gradation, and traffic level. However, existing models are deterministic as they incorporate mean values of the input parameters and yield an average skid number value for a pavement section. Consequently, these models are not capable of accounting for variability in material properties and associated variation in the predicted skid number values. This study aims to develop a probabilistic approach that determines the mean as well as the variation in skid number in a pavement section. The efficacy of this approach is demonstrated by selecting one of the validated models that incorporate a wide range of aggregate characteristics. The results showed that while the average skid number predicted by the deterministic model may satisfy a required threshold/specification value, a fair percentage of the distribution could fall below the required value. The probabilistic approach is useful for engineers to determine the effect of aggregate characteristics on skid resistance distribution and to identify risks associated with the probability of skid resistance values in a pavement section fall below the required limit.

This paper aims to quantify the effect of modified mixture volumetrics and compaction effort on surface characteristics of asphalt pavements. Specimens were prepared using PG 64-10 asphalt binder m...

Conspicuous consumption is a behavior that is becoming prevalent in today's world. Although limited attention has been given to conspicuous consumption in a digital world, it is a behavior that everyone practices, in different degrees. This article sets out to reveal and examine the underlying psychological motivations of online conspicuous consumption. Semi-structured interviews are adopted as a qualitative technique. The interviews were conducted with fifteen Jordanian residents who have access to the internet and social media. The findings reveal that the four proposed psychological motivations (envy, materialism, narcissism, and social comparison) are of significant influence on users' online conspicuous consumption. This study introduces a comprehensive model of online conspicuous consumption that was not addressed earlier in the literature and provides a viable foundation for future research in this context. Furthermore, the results will help marketing managers to better understand and manage their strategies in reference to users' psychological motivations when posting online.

The subgrade layer, upon which the pavement is constructed, will have a large impact on structural design. The study aims at characterizing permanent deformation properties of cohesive subgrade materials including. A new testing procedure, stage loading, was used to test the permanent deformation of subgrade materials at different stress levels and load repetitions; this technique allows researchers to explore the effect of stress history on the accumulation of plastic deformation besides saving time, effort, and test specimens. The permanent deformation results showed a constant increasing rate of plastic strain at higher stress levels. The results obtained could be used to help engineers in characterizing the cohesive subgrade materials. Statistically, soil type and water content were found to be statistically significant at the 0.05 significance level, whereas, at the 0.1 significance level stress level, soil type and water content were found to be significant factors in affecting permanent stain.

Aim/Purpose: The main objective of this study is to explore students’ beliefs with regard to social media use (SMU) in higher education and the consequences of such use on the perception of their academic performance. Additionally, the study aims to determine the major influential factors with regard to SMU in student learning settings as a means of enhancing their performance. To achieve these objectives, drawing on the literature related to SMU in higher education settings, a research model has been developed. Background: Social media platforms have led to a significant transformation with regard to the communication landscape in higher education in terms of offering enhanced learning and improved teaching experience. Nevertheless, little is known, particularly in developing countries such as Jordan, as to whether or not the use of such platforms by students in higher education increases the perceptions of their academic performance. Therefore, this study has developed a model to examine the perceptions of higher education students with regard to social media use and its effect on their performance. Methodology: The Structural Equation Modelling approach is used to analyze data collected via an online survey in the form of a questionnaire to examine the use of such a model. The study sample is drawn from undergraduate and postgraduate students from three universities (one public and two private) in Jordan. Convenience sampling is used to collect data. Out of 730 sent questionnaire, 513 responses were received, of which 403 were deemed qualified to be part of the data analysis process. Contribution: This study contributes to the literature on social media in higher education by enhancing our understanding of the perceptions of higher education students on the use of social media in their learning. The tested model can be used as a benchmark for other studies that target the impact of social media on student performance in higher education. Findings: The results reveal that perceptions of (1) usefulness, collaborative learning, enhanced communication, enjoyment, and ease of use of social media have a positive effect on the use of such media in student learning; (2) resource sharing has an insignificant effect on social media use in student learning, and (3) social media use has a positive influence on students’ perceptions of their academic performance. Recommendations for Practitioners: Senior management and policy makers in higher education institutions will have to train faculty members on effective strategies and methods in order to effectively integrate social media into education. This would equip faculty members with the necessary digital skills needed to help them to be fully informed regarding the benefits of social media and its tools in learning and teaching activities and would also allow them to avoid any possible drawbacks. Furthermore, faculty members should reconsider their current techniques and strategies, and adopt new methods in their teaching that encourage students to use social media platforms as part of their learning. For example, they can regularly post discussions and assignments on social media platforms to inculcate the habit of using such platforms among students for educational purposes. Students, on the other hand, should be aware of the implications and potential advantageous aspects of SMU in their learning. This could be done by conducting regular workshops and seminars in the various faculties and schools at universities. Recommendation for Researchers: Researchers are encouraged to investigate additional factors that might influence the use of social media by students as well as faculty members. Specially, an emphasis should be given to identify any potential obstacles that might hinder the use of social media in higher education. Impact on Society: Social media is not only useful for socializing, but also it can be an effective educational tool that enhance students’ performance in higher education. Future Research: Although the collected data support the research model, this study is subjected to various limitations that need to be tackled by further studies. This study is based on the principles of quantitative research design. Data for this study was collected via survey questionnaires. Accordingly, future studies may consider a qualitative research design in order to uncover additional factors that may impact the use of social media on the part of higher education students. This would allow researchers to generate in-depth insights and a holistic understanding of SMU by higher education students. A convenience sampling method was employed to select respondents for this study. The respondents who participated in this study were from three universities (one public and two private) in Jordan. Accordingly, future research is deemed to be necessary to achieve a degree of generalizability regarding the findings of this study.

Most of the pavement structures, worldwide, are made with Hot Mix Asphalt (HMA) as this is one of the most economical materials available and it is also very suitable for different climatic conditions. However, the HMA pavement normally requires frequent maintenance and rehabilitation due to damages caused by excessive traffic loading. Therefore, one of the alternatives to minimize the damage of pavement and to prolong its service life is to use modifiers that are used in the asphalt pavements. This study demonstrates the properties of HMA mixed with coir fiber. The laboratory results reveal that coir fiber is effective in increasing the Marshall stability of ordinary HMA mixes. The coir fiber increases the Marshall stability of ordinary HMA by 41%. Consequently, coir fiber has promising potential in modifying asphalt mixtures. Additionally, comprehensive statistical analysis was carried out to validate conclusions drawn based on laboratory results. It was clearly concluded, statistically, that changing the Coir Fiber Content (CFC) has a significant effect on almost all Marshall test values.

This study aimed to investigate the effect of freeze and thaw (FT) cycles on the performance of asphalt concrete (AC) mixtures modified by partial replacement of mineral filler of the aggregate with natural bentonite clay (NBC) in order to reduce damage that occurs due to rapid FT cycles within the pavement structure. After exposure to FT cycles, AC mixture stability is reduced and becomes lower than minimum requirements, which leads to earlier damage of pavement. In order to enhance the AC mixture’s abilities to sustain severe FT cycles, this study used NBC amounts as a substitute for mineral filler by weight of its portion of the total aggregate: 5%, 10%, 15%, and 20%. Marshall stability, flow, and FT cycles were tested, and interior damage degree was assessed by a nondestructive test called ultrasonic pulse velocity (UPV). The results revealed the viability of combining NBC with asphalt mixtures for the purpose of improving the mixtures’ properties, particularly in environments where asphalt pavement is exposed to alternating FT cycles. The results also revealed that replacement of filler with NBC by 5% in AC mixtures reduced the damage caused over 8 continuous weeks of rapid FT cycles by 13%, which, in future applications, would reduce maintenance cost and prolong the pavement’s service life.

More research is needed on the drivers of irrational antibiotic prescribing among healthcare professionals and to ensure effective prescribing and an adequate understanding of the issue of antibiotic resistance. This study aimed at evaluating prescribers’ knowledge, attitudes and behaviors about antibiotic use and antibiotic resistance. A cross-sectional study was conducted utilizing an online questionnaire and included physicians and dentists from all sectors in Jordan. A total of 613 prescribers were included (physicians n = 409, dentists n = 204). Respondents’ knowledge on effective use, unnecessary use or associated side effects of antibiotics was high (&gt, 90%), compared with their knowledge on the spread of antibiotic resistance (62.2%). For ease of access to the required guidelines on managing infections, and to materials that advise on prudent antibiotic use and antibiotic resistance, prescribers agreed in 62% and 46.1% of cases, respectively. 28.4% of respondents had prescribed antibiotics when they would have preferred not to do so more than once a day or more than once a week. Among respondents who prescribed antibiotics, 63.4% would never or rarely give out resources on prudent use of antibiotics for infections. The findings are of importance to inform antibiotic stewardships about relevant interventions aimed at changing prescribers’ behaviors and improving antibiotic prescribing practices.

The major objective of this study is to investigate the possibility of using Artificial Neural Networks in creating prediction models capable of estimating Bending Beam Rheometer outputs; namely creep stiffness, and m-value based on test temperature, modifier content; in our case waste vegetable oil, and testing time interval. A feedforward backpropagation neural network with Bayesian Regulation training algorithm and an SSE performance function was implemented. It was found that the neural network model shows high predictive powers with training and testing performance of 99.8% and 99.2% respectively. Plots between laboratory obtained values and neural network predicted outputs were also considered, and a strong correlation between the two methods was concluded. Therefore, it was reasonable to state that using neural networks to build prediction models in order to find BBR test values is justified.

This research investigates the effect of adding three different modifiers to laboratory-prepared Superpave asphalt concrete mixtures to evaluate their ability to strengthen and reinforce asphalt co...

The objective of this work is to provide a literature survey on the research attempts made in the field of ejector refrigeration systems and the studies made on the ejector as a component. The review is to be structured four parts. In the first part, the focus is on the effect of different geometrical aspects affecting the performance of the ejector in terms of entertainment ratio, pressure ratio and other flow related features, where various geometrical aspects are reviewed including primary nozzle position, area ratio, mixing suction length. The second part is dedicated to reviewing the attempts made in proposing different mathematical models to investigate the behavior of the ejector. In addition, experimental flow visualization attempts are also presented. In the third part, the study focus is on the main ejector refrigeration systems proposed. Finally, the effect of using different working fluids on the performance of the ejector refrigeration system will be reviewed.

This paper aims to assess passenger cars’ speed on urban channelized right-turn roadways at signalized intersections under the free-flow traffic conditions. Stepwise regression and artificial neural network (ANN) were used to develop speed models. Geometrics data for twenty-one channelized right-turns at seventeen signalized intersections in urban areas were collected. Analysis results showed a linear relationship between right-turn roadway radius and speed. Other geometric parameters were found statistically significant at the 95% confidence level. The coefficient of determinations ( $${R}^{2})$$ was found to be 87.9%, 94.2% and 97% for the average speed, 85th percentile speed regression models and ANN model, respectively. Results obtained from the comparison analysis showed that equations developed for horizontal curves are recommended with caution for predicting speed on right-turns due to differences in the range of radius values. The regression equation $$(\hbox {Eq.}~8: V_\mathrm{avg} =10.904+0.314\,R+2.286\, \mathrm{Ds}+0.046\,\mathrm{SD}+0.288\,W)$$ developed in this study offers relatively better prediction accuracy compared to all other previous models. Besides, the ANN model outperformed all other models including the developed regression equation of this study. Care should be taken when using the findings of this study as they are exclusive to the conditions and locality under which this study was performed. To generalize the results, further validation is needed using data from different localities and drivers with diverse behaviors. In addition, models of this research are for speed predictions if curves’ radii are within the range of data used (10–135 m) in order to avoid extrapolation.

This paper investigates the effect of using different proportions (0%, 1%, 3%, 5%) of FORTA-FI fiber on asphalt mixtures static creep behavior under different compactive efforts (35 blows, 50 blows, 75 blows) and testing temperatures (25°C, 40°C, 55°C). The accumulated micro-strain was found to increase as temperature increases and stiffness modulus was found to decrease as temperature increases. These results are expected due to the viscoelastic nature of asphalt mixtures. Additionally, feed-forward back-propagation Artificial Neural Networks (ANN) was utilized in order to build a model that describes and predicts the relationship between deformation and stiffness modulus with multiple variables such as; Temperature (Temp), Fiber Content (FC) and Compactive Effort (CE). Evidently, a powerful predictive model was developed with Coefficient of Determination (R2) of 94%. The results using the SPSS statistical software of the two-way and three-way Analysis of Variance (ANOVA) tools showed that temperature and FORTA-FI content have significant interactions effects. Whereas, compactive effort effect on stiffness modulus was insignificant. Further, results obtained using Minitab statistical software confirmed the above findings.

This study aims to examine the impact of servant leadership on organizational trust and mediating role of organizational culture for the mentioned relationship for employees in the Kuwaiti Ministry of Higher Education. A survey questionnaire was used as the main instrument for data collection. A total of 285 questionnaires were distributed among the Kuwaiti Ministry of Higher Education employees. In total, 248 valid questionnaires to analysis were returned equivalent to 87% response rate. Data analysis was conducted with the help of PLS-SEM to determine the level of relationships among servant leadership, organizational trust, and organizational culture. According to the obtained findings, there is a positive impact of servant leadership on organizational trust, and organizational culture has a partially mediated role in the relationship between servant leadership and organizational trust. The study findings motivate future studies to carry out studies of the same caliber in other sectors to obtain different perspectives.

Background Elevated levels of blood lipids are considered a major modifiable risk factor for the development of cardiovascular diseases. The optimal management of dyslipidemia remains inadequate worldwide. Accordingly, there is an increasing need to evaluate the basis that health care providers are using to control dyslipidemia. Aim To evaluate the awareness of Jordanian physicians about the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for dyslipidemia management. Method A written questionnaire was distributed to 250 physicians from different areas of Jordan during seven months period (from February 2018 until the end of August 2018). The target population is composed of the following categories: juniors, residents, fellows, and consultants who were recruited from private, government, and military practice settings. The validated developed questionnaire was distributed by trained medical personnel. Results A total of 207 physicians filled and handed back the questionnaire. The response rate was 82.8%. Generally, there was a difference in the level of knowledge between physicians (juniors/ residents/ consultants) while there was no difference between genders or practice settings (private or government). The current study showed that the awareness of physicians in different areas of Jordan regarding the 2013 (ACC/AHA) dyslipidemia guidelines is suboptimal. Conclusion Results indicated low levels of knowledge of 2013 ACC/AHA guidelines for the management of dyslipidemia among physicians in Jordan. Hence, multiple interventions are needed to be implemented in order to increase the level of awareness among Jordanian physicians.

This study evaluated potential improvements in the physical and rheological properties of asphalt binders modified with crumb tire rubber (CTR), microcrystalline synthetic wax (MSW), and na...

The laboratory simulation of asphalt pavement surface deterioration is usually a lengthy process. In this study, a predictive tool (or equation) was developed to calculate the steady state torque-based coefficient of friction (Tfr) and the onset of steady state. To this end, nonlinear regression was utilized and a Graphical User Interface (GUI) was built in MATLAB®. The purpose of the tool is to reduce experimentation time. Eight sets of data were used. Data was obtained from laboratory testing conducted on eight Job Mix Formulas (JMFs) of highway materials obtained from the State of Ohio. The data was collected using a power unit (or motor) attached to a newly developed asphalt polishing machine to detect surface deterioration. The experiment measures torque values that are directly related to friction values; the so called torque-based coefficients of friction. The main characteristic of the equation allows for calculating the steady state Tfr and the onset of steady state. This enables the experimenter to determine when steady state is reached at a desired tolerance during the test, thus reducing the time required for testing. It was concluded that testing time can be reduced significantly (a range of 40% to 50% savings), which may be received positively by Departments of Transportation and other highway material testing laboratories around the world.

The reproduction of asphalt pavement surface texture deterioration in the laboratory is usually lengthy. The objective of this work is to find an analytical tool to predict the steady-state mean te...

The main objective of this study is to check the possibility of upgrading at-grade roundabouts to Turbo roundabouts considering the Jordanian driving conditions. It is also to check how such upgrade is going to affect performance measures of the studied areas including safety, capacity, queue length, delay, and level of service (LOS). Thus, three roundabouts were selected and analyzed using SIDRA software under off-peak, morning peak and evening peak traffic conditions to obtain the actual capacity, queue length, delay, and LOS values under the current design. Then two designs were applied for each roundabout according to Dutch design guideline manual using TORUS software by changing inner radius and opening width. The generated designs were analyzed using VISSIM software under the original traffic conditions, to evaluate the effect of introducing turbo roundabout system as a replacement to the conventional roundabout system. The results of this study indicate that turbo roundabouts offer higher capacities, less delays and better LOS compared to existing intersections. In addition, introducing turbo roundabouts might offer higher safety levels than conventional roundabouts; as conflict points were reduced from 32 on two-lane conventional roundabouts to only 12 on the proposed turbo roundabouts. Consequently, reconstruction of intersections was warranted.

The nanostructure design of near zero reflection coating for Si substrates by using ZnO Nanoneedles (ZnONN) is performed and optimized for the visible spectral range. The design investigates the ZnONN tip to body ratio effect on the anti-reflection coating properties. Different tip to body ratios are used on Si substrates. Around zero reflection is achieved by the Nanoneedles structure design presented in this work, leading to minimal reflection losses from the Si surface. The current design evolves a solution to optical losses and surface contamination effects associated with Si solar cells.

The goal of this study is to check the validity of using the waste vegetable oil as an additive to the asphalt cement, to be used later in the construction of flexible pavements. This will be considered as a proper and legal method of disposing this waste material. In this study, 1%, 2%, 4%, 6%, and 8% of waste vegetable oil by volume of the asphalt cement were used. Several laboratory tests were performed on the original and waste vegetable oil-modified asphalt cements. It was found that choosing the appropriate amount of waste vegetable oil will improve most of the tested properties. Therefore, it can be concluded that using the suitable amount of waste vegetable oil as a cement modifier is feasible, and can be considered as a proper and legal method for disposing the waste vegetable oil. Keywords: Asphalt cement, Waste vegetable oil, Asphalt cement modifier, Road construction, Waste material disposal

In this work, the performance of an ejector refrigeration system using nano-refrigerants is investigated. A new hypothesis is proposed for flow boiling modeling, where nanoparticles are assumed to not migrate to the vapor phase as phase changes occur continuously; this causes a significant increase in nanoparticle mass fraction for high vapor quality values. This assumption shows a reasonable correlation with previously published data for R113/CuO mixtures, where an average deviation of 9.24% was obtained. A parametric analysis is performed to investigate the variation in heat transfer coefficient (HTC) with temperature, nanoparticle type, size, and mass fraction. Finally, the effect of nanoparticles on the coefficient of performance (COP) of the ejector refrigeration cycle as a response to the augmented flow boiling HTC is investigated by simulating a 5-kW cooling refrigeration cycle. Considering the advantage of using nano-refrigerants, a higher quality vapor was attained at the evaporator exit, resulting in an increase in the enthalpy difference in the evaporator in the ejector cooling cycle. As a result, a lower mass flux inside the evaporator is required to attain the same cooling capacity. Improved refrigerant-side HTCs improve the overall HTCs of the evaporator, allowing the evaporator to operate at lower temperature differences and higher pressures, which consequently increases the cycle COPs. Furthermore, the refrigerant vapor quality increases at the evaporator exit, leading to an enhanced COP of the cycle. The augmentation in COP reached 24.7% and 12.61% for R134a with 2 wt.% CuO and Al2O3, respectively, whereas the vapor quality for the refrigerant leaving the evaporator increased from 0.7616 for the case of the pure refrigerant to 0.8212 for R134a/CuO 2 wt.% nano-refrigerant.

When designing pavements, there are three fundamental external design parameters to evaluate (1) the characteristics of the subgrade upon which the pavement is placed, (2) the applied loads and (3) the environment. This study is based on laboratory testing of cohesive subgrade materials to characterise their resilient modulus properties and to identify the main controlling factors of this property. Experimental results showed a slight increase in resilient modulus values with an increase in confining pressure and a noteworthy decrease in resilient modulus accompanied by an increase in deviatoric stress. This finding was verified statistically. Based on the independent samples t-test analysis, it was revealed that soil type and water content caused statistically significant difference in resilient modulus values. According to one-way ANOVA, deviatoric stress turned out to be influential while confining pressure did not. In addition, it was demonstrated using the two-way ANOVA that none of the two-f...

Modern institution plays crucial role in motivated towards a competitive age. A university must improve and develop their teaching and learning process related to the new innovations of educational technologies. The Hashemite Kingdome of Jordan, as one of the developing countries, focuses on higher education sector as one of the most influential sectors to develop social, economic, and human growth in the country. However, the King, the government, and the leadership of higher education institutions in Jordan face many challenges to enhance the quality of the output in universities and to sustain the scientific research. Sadly, there are lack of studies and programs that measure the satisfaction of using e-learning to improve the educational process in Jordanian universities from managerial perspective. The main purpose of this study is to examine and measure the satisfaction factors by employed Information System Success Model (ISSM) related to the usage and sustain use of e-learning in Jordanian public universities. A self-administered survey was conducted on 117of academics selected as deans of faculties, academic departments’ chairs, and managers of computer and e-learning centers. About 100 participants (85%) have responded. The results show that perceived usefulness, management support,self-efficacy, technical support, and training have a significant relationship with the satisfaction of the usage of e-learning system. On the other hand, the study grants a good indicator to the higher education leaderships about the quality of used e-learning in the Jordanian public universities.

Electronic learning (e-learning) is considered in a beginning stage in the developing nations such as Arab world especially in the field of higher education system. Jordan as one of the developing nation though appreciates the importance of universities and their role in achieving an economic prosperity through the growth of human resources; unfortunately, the adoption of e-learning is quite low among the students in the Jordanian universities. This study therefore, is concerned with the improvement of educational process through the adoption of e-learning tools among the students in the Jordanian higher education institutions. The main purpose of this study is to examine the potential prominent factors related to the adoption and usage of Information and Communication Technology (ICT) in the Jordanian public universities among the students. The main challenge of the study is to provide such an understanding on the e-learning usage by applying the Technology Acceptance Model (TAM), Diffusion of Innovation (DOI) theory, and Decomposed Theory of Planned Behaviour (DTPB). A self-administrated survey was conducted on 350 of students selected from public universities in Jordan. A total of 253 participants (72%) have responded, and series of data analyses of variables measurement for reliability and validity test of predictors were performed. The results of the analysis, however, contribute a new model which is considered as a novel model in such studies. The findings show that Attitude towards Technology (ATT), have positively affected the Behavioural Intention (BI) to use technologies in the higher educational system among students. Moreover, there is a significant relationship between students’ perception of technology characteristics and their ATT using the e-learning technologies in the higher education system.

The aim of this study is to examine the factors affecting students' intention to use cloud computing in the Jordanian universities. To achieve this purpose, a quantitative research approach which is a survey-based was deployed. Around 400 questionnaires were distributed randomly to Information Technology (IT) students at four universities in Jordan and only 236 valid questionnaires were received. Using multiple regression technique, the results revealed that perceived usefulness, perceived ease of use, perceived security, perceived speed of access, and perceived cost of usage were significantly influencing the students' intention to accept and use cloud computing while the Affect was not. Furthermore, the results indicated that the developed model explains 50.4% of the variance in the students' intention to use cloud computing. Practically, the results of this study are considered fruitful for the universities and students to increase the usage of cloud computing in the educational settings.

Highway agencies continuously strive to maintain adequate surface friction (or skid resistance) at the interface between vehicle tyres and pavement surfaces to enhance the available friction during...

Six different shapes of zinc oxide (ZnO) nanostructured antireflective coatings on Si substrate, namely hemispheres, pyramids, motheye-like, cubes, rods and hexagonal prisms, were modeled numerically using finite element simulation, by solving Maxwell wave equation for periodic nanostructure arrays. COMSOL Multiphysics commercial package was used to perform the simulation by adopting the wave optics module. Geometrical parameters including structure size and period were studied in order to obtain better insight on how light and matter interaction is affected by structure geometry. However, among the studied structure geometries, hemispherical ones have the worst optical performance with a maximum reflectance of 45% for a 20 nm hemisphere radius. Pyramidal, motheye and cubic shapes yielded an intermediate optical performance while rod and hexagonal shapes revealed a minimum reflectance (less than 5%) values over a wide range of wavelengths and also showing interesting interference patterns., This research was fully supported by the Jordanian Royal Hashemite Court under the Royal Initiative for Innovative Projects in Nanotechnology.

This study explores the effect of three types of modifiers on the rutting and resilient modulus performance of asphalt concrete mixtures using the dynamic creep test. Modifiers have been added to the asphalt binder at optimum percentages that have been chosen based on a previous study by the authors. 108 Superpave asphalt mixture specimens have been prepared. In this study, the dynamic creep test has been conducted at different temperatures (25 °C, 40 °C and 55 °C) and at three loading frequencies (1, 4 and 8 Hz). Accumulated axial micro-strain, creep stiffness modulus, and resilient modulus values have been measured. The results have showed an enhancement in the rutting resistance at high frequencies when adding the modifiers. The Crump Tire Rubber modified mixtures have showed the best results at high temperatures, and the Nano Silica modified mixtures had the best outcomes at intermediate temperatures, while the Microcrystalline Synthetic Wax modified mixtures have achieved the best results at lower temperatures. Statistical and regression analyses have showed that changing temperature, frequency, and modifier type had a significant effect on the accumulated axial micro-strain, creep stiffness modulus, and resilient modulus values. Models have been generated with relatively high coefficients of determination (R2) and adjusted R2, indicating their ability in explaining much of the variability in the response variables.

The primary objective of this work is to identify influential factors on asphalt pavement texture properties and to estimate their relative importance. The analysis is descriptive as well as analytical. Non-parametric procedures and multiple regression techniques were used to identify the significant categorical and quantitative predictors, respectively. The analysis showed that all categorical variables (location, design method, aggregate type, and asphalt binder grade) have statistically significant effect on macrotexture values. The regression analysis and model selection using stepwise regression also showed that air void, nominal maximum aggregate size and percent of trucks or truck traffic count are significant predictors on macrotexture values. Conventional and wavelet-based macrotexture values were statistically analysed in this study.

The new and rapid growth of technologies has changed the face of the world. It is being considered the umbrella for the communication and networking devices and software with applications. In fact, the development of ICT strategy is vital for the growth of the knowledge economy in developing countries. Information and Communication Technology (ICT) is considered in a beginning stage in the developing countries such as Arab world especially in the field of teaching and learning process. This study therefore, is focused with the development of e-learning process through the adoption of ICT among the academic staffs in the Jordanian universities. The main purpose of this study is to examine the potential prominent factors related to the usage of ICT in the public universities among the academic staff. The main challenge of the study is to fully understanding the factor affecting on the ICT usage by applying the Decomposed Theory of Planned Behavior (DTPB). The findings show that self-efficacy (SE), and facilitating condition (FC) have positively affected the Behavioral Intention (BI) to use ICT in the higher educational system among academic staff. There is also a significant relationship between academic staff's perception of technology characteristics and their Perceived Behavioral Control (PBC) towards using the technology in the educational system.