Relationship between creep time dependent index and Paris Law parameters for bituminous mixtures

Published ArticleBituminous mixtures undergo cracking, either top-down or bottom-up, as a consequence of the repeated application of traffic loads, thermal cycling or a combination of the two mechanisms. Cracking is considered as one of the major distress modes in asphalt pavements. This study presents a method to characterise crack resistance of asphaltic mixtures containing waste materials using a semi-circular bending (SCB) fracture test. Three different bituminous mixtures containing incinerator bottom ash waste and one control mix, containing limestone, were tested under cycling SCB loading conditions at 5°C and the results were interpreted using Paris Law. The same mixtures were also tested under controlled stress creep conditions at the same temperature. This paper examines the link between the time dependent index from creep tests with the n parameter from the Paris Law model, based on visco-elastic continuum damage mechanics analysis and linear elastic fracture mechanics principles

Performance enhancement of large scale networks with heterogeneous traffic.

Finally, these findings are applied towards improving the performance of the Differentiated Services architecture by developing a new Refined Assured Forwarding framework where heterogeneous traffic flows share the same aggregate class. The new framework requires minimal modification to the existing Diffserv routers. The efficiency of the new architecture in enhancing the performance of Diffserv is demonstrated by simulation results under different traffic scenarios.This dissertation builds on the notion that segregating traffic with disparate characteristics into separate channels generally results in a better performance. Through a quantitative analysis, it precisely defines the number of classes and the allocation of traffic into these classes that will lead to optimal performance from a latency standpoint. Additionally, it weakens the most generally used assumption of exponential or geometric distribution of traffic service time in the integration versus segregation studies to date by including self-similarity in network traffic.The dissertation also develops a pricing model based on resource usage in a system with segregated channels. Based on analytical results, this dissertation proposes a scheme whereby a service provider can develop compensatory and fair prices for customers with varying QoS requirements under a wide variety of ambient traffic scenarios.This dissertation provides novel techniques for improving the Quality of Service by enhancing the performance of queue management in large scale packet switched networks with a high volume of traffic. Networks combine traffic from multiple sources which have disparate characteristics. Multiplexing such heterogeneous traffic usually results in adverse effects on the overall performance of the network

Cultural & Responsible Tourism

Fidaa Alfalata's & Mostafa Hassan's poster on cultural tourism

Influence of Climate Change on Probability of Carbonation-Induced Corrosion Initiation

The consequences of climate change on infrastructure, particularly reinforced concrete (RC) bridges, have rapidly increased in recent years. These consequences are primarily driven by the surge in CO2 emissions, which significantly impacts the carbonation depth of RC structures. This study aims to investigate the probability of carbonation-induced corrosion initiation (PCICI) in RC bridge elements. To achieve this, the investigation incorporates a range of concrete covers, varying from 30 to 50 mm, and considers different concrete mixes with cement contents of 400, 350, and 250 kg/m3. The investigation utilizes the Monte-Carlo simulation method, considering different representative concentration pathways (RCPs) to account for two emission scenarios: RCP2.6 (low emission scenario) and RCP8.5 (high emission scenario). By analyzing projected CO2 concentrations and maximum temperature, the study provides insights into the potential corrosion initiation risks in RC bridges. The findings indicated a significant 66.3% increase in PCICI for a cement content of 250 kg/m3, compared to 400 kg/m3, under the RCP8.5 scenario, specifically when using a concrete cover of 30 mm by 2100. The study also revealed that the PCICI approached an approximate value of zero when concrete covers were set at 45 and 50 mm regardless of the variations in cement contents and the duration considered, for both the RCP2.6 and RCP8.5 scenarios

Student performance on computer-based tests versus paper-based tests in introductory financial accounting: UAE evidence

© 2018, Allied Academies. This study examines whether the use of technology-based assessment tool affects the examinations\u27 scores of students from both genders. The study, therefore, ascertains whether the mode of student testing (computer-based or paper-based) in an introductory-level financial accounting course impacted students\u27 scores (a direct measure of learning). In doing so, the study relies on experimental design wherein the type of examination is being controlled together with other contextual variables such as timing of the exam, instructors, and the gender of students. The sample consists of 78 students undertaking financial accounting courses at Zayed University during the summer semester. A simple difference in means statistics test shows that there is no statistically significant difference between the students\u27 paper-based and computerbased scores. However, benchmark regression analysis showed that males performed better than females on CBT, and females outperformed males on PBT. The paper provides evidence from the Gulf region as of how technology-based assessment is affected by the gender, which matter needs to be addressed by university instructors working in Middle East universities

The Role of Writing Center Tutorials of ESL Students: Exploring Tutors, Tutees, and Instructors’ Perceptions

The purpose of this study was to investigate the role of the writing center tutorials. Based on the assumptions of the constructivist theory, this research tried to present a cognitive framework for better tutoring at the writing center and suggested better accommodations for ESL tutees. this exploratory study investigated the role of the writing center tutorials offered to ESL students through the perceptions of tutors, ESL tutees, and university instructors. Methods. Eighty nine international /ESL students and 23 tutors were selected. They were given a survey to respond to. Afterwards ten out of the 89 students and ten out of the 23 tutors were interviewed. Volunteering ESL students, tutors, and ten university faculty were interviewed to explore their perceptions toward the writing center tutorials. Moreover, the researcher observed the two writing centers in which the study was conducted. Data analysis. This Mixed Methods Research study combined a quantitative design using surveys and a qualitative part utilizing interviews, and non-participatory observation. Therefore, the result of the survey administered were statistically analyzed using independent samples T-tests. After the interviews, coding an analysis began to investigate similarities and dissimilarities among the participants’ responses. Tables of frequency were designed to examine the range between outliers and calculate percentages of each respondent in comparison to the other group members. Each theme had a representative code, a formulated meaning, frequency of the respondent, and a significant statement asserting such theme. The themes were collected across all cases to show frequency. Findings. The findings of this study revealed that the writing center is effective in improving ESL tutees’ writing skills that may also be transferable to their future careers. Additionally, this study asserted that the non-directive tutoring approach, the commonly used in the U.S. writing centers, is not the only effective tutoring mode for all ESL tutees. Most tutors, according to this study, may not apply this prescriptive non-directive tutoring. Consequently, the study concluded that a reasonable balance between the tutoring dichotomies can make a difference with ESL students. Furthermore, the study emphasized that tutors need specialized ESL training to better assist and accommodate ESL tutees

Perspectives of the stakeholders of the public transportation system on ICT solutions applicability in the Free State, South Africa

Published Conference ProceedingsInformation Communication Technologies have recently been adopted by transportation systems around the world to improve their services. In adopting these technologies, the stakeholders‘ involvement and perceptions regarding ICT should be considered. This paper, considering the study area, reflects on the perceptions of different stakeholders of the public transportation system towards the introduction of ICT solutions to the system. The methodology adopted was to understand the expectations of drivers, passengers and operators on integrating ICT solutions into the public transportation system, focusing on mini-bus taxis and Interstate Bus Line buses. The significant results of the study show that ICTs are anticipated and long overdue development to the system but the stakeholders have varying expectations. These results reflect on the priorities of the stakeholders, i.e., passengers yearn for improved service quality; drivers are concerned with their working conditions while the operators‘ interests are profit motivated. This paper highlights the ICT interests of passengers, drivers and operators. It compares passengers‘ needs, in terms of technologies, to improve the public transportations system against what the operators are enthusiastic to provide