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Influence of High Temperature on Geopolymer Powders Concrete
Get PDFA recent advancement in building construction is geopolymer concrete (GP), which uses pozzolanic materials like fly ash in place of cement and is activated by an alkaline solution. This study evaluates the impact of various parameters on the compressive strength of geopolymer concrete (GP) by analyzing experimental results from nine GP mixtures. In this study, the effects of two different fibers—steel and polypropylene—were used to calculate the impact of additional fibers on geopolymer concrete following exposure to temperatures of 200 , 400 , and 600° C.
Examining the impacts of two ratios of silica fume (10 and 20%)
The durability parameters according to elevated temperature are visual inspection, weight reduction, and residual compressive strength. for nine fly ash-based geopolymer mixtures, steel fibers (SF) and polypropylene fibers (PP) were used in both mono and hybrid form. Steel and polypropylene fibers were added to the geopolymer concrete mix in varying fractions (0.15%, 1%, and 2%). In hybrid mixes, steel fibers replaced polypropylene fibers at a 2% inclusion rate, Additionally, one extra-plain series devoid of fiber was cast. According to experimental test results, using different kinds of fibers improved the geopolymer composites\u27 performance at higher temperatures. At all elevated temperatures, the residual compressive strength of Steel Fiber Reinforced Geopolymer Concrete (SFRG) was much higher than that of polypropylene fiber reinforced geopolymer concrete (PFRG) at 400°C The size of the cube decreases,. the chemical bonds inside it break down, and voids and deformations appear on the cube\u27s surfaces when samples are exposed to temperatures
above 300 degrees Celsius. Additionally, the resistance of geopolymer concrete decreases by 15–20% in compressive strength
Numerical Study for Strengthening Hexagonal Castellated Steel Beams Using Hexagonal Ring Stiffeners
Get PDFThis paper investigates numerically how the castellated steel beams are affected by the addition of hexagonal stiffeners around hexagonal web openings. Increasing the CSBs\u27 load-bearing capacity and improving their overall structural behavior are the main objectives of this strengthening technique. Although there are different failure modes as a result of castellation, the main emphasis of this study is web post-buckling. Using ABAQUS software, a 3D finite element model is created to analyze the beam\u27s behavior. The model\u27s accuracy was validated by comparing its results with those from previous experimental studies. Failure loads, failure modes, and load-deflection curves of CSBs are investigated in this study. An extensive parametric study is conducted on simply supported castellated steel beams subjected to a concentrated load in mid-span. The study investigates the effects of hexagonal stiffener properties, such as stiffener thickness (ts) and stiffener width (bs), on the load capacity and failure modes. According to the parametric analysis, adding hexagonal stiffeners to CSBs from both sides strengthens them and improves their load-bearing capacity while also reducing web post-buckling. The ultimate load increases as the stiffener thickness (ts) is increased from 4 mm to 10 mm. In contrast, increasing the stiffener width (bs) from 20 mm to 40 mm enhances the ultimate load, but to a lesser extent
Degree of Control by Faculty Members over their Online Classes at Yarmouk University: A Student Perspective
Get PDFThis study aimed to examine the degree to which faculty members at Yarmouk University control their online classes from the students\u27 perspective and to explore the impact of variables such as gender, educational level, and specialization. The study sample consisted of 462 students, selected using a convenience sampling method. The study employed a descriptive survey method, and to achieve its objectives, a questionnaire consisting of 40 items was designed, covering three domains. The results revealed that the degree of control perceived by students regarding faculty members\u27 management of their online classes was high. The study also found statistically significant differences at the significance level of (α = 0.05) in the mean scores of the sample members across all domains of the study tool, as well as in the overall score, attributed to gender (favoring males), educational level (favoring graduate students), and specialization (favoring scientific disciplines)
Risk Management among School Principals in Ramtha District and its Relationship with Organizational Competence from the Teachers\u27 Perspective
Get PDFThis study aimed to identify risk management practices among school principals in the Ramtha district and their relationship with organizational competence from the teachers\u27 perspective. The researchers used the descriptive correlational survey method, with a questionnaire as the data collection tool. The questionnaire was applied to a sample of 737 male and female teachers, selected through simple random sampling. The results showed that the level of risk management practices among school principals in the Ramtha district was high, and the level of organizational competence was also high. Additionally, there was a moderate positive correlation that was statistically significant at the significance level (α=0.05) between the degree of risk management practices and the degree of organizational competence among school principals in the Ramtha district. The study recommends that school principals continue to monitor risk management in the educational process in the areas of (supervision and follow-up, planning, implementation, and evaluation), due to its importance in achieving the educational process\u27s goals, mission, and vision
Evaluating the effectiveness of cinnamon oil on pain severity caused by needle pick during inferior alveolar nerve block in children
Get PDFObjectives: Despite the great development witnessed by dentistry, pain during the insertion of a local anesthesia needle is still the main cause of fear and anxiety in children, and with the spread of many methods to relieve pain, research is still ongoing to find an effective surface anesthetic to relieve pain well, so the aim of this research was to take advantage of the available and cheap non-pharmacological natural materials in achieving this goal.
Materials and Methods: A randomized, double-blind clinical study was conducted involving 60 children from the Pediatric Dentistry Department of Damascus University. Cooperative children were selected (according to the Frankl scale Grade 3 and 4), within the age group of 7-11 years. The sample was divided into two groups where each group included 30 children, namely the cinnamon oil group and the benzocaine gel group, each of the substances was applied for 3 minutes. The pain was assessed subjectively by the child using the scale Wong Backer Faces modified by Al Monaqel using a wooden board designed with measurements(60-20) and the image of the scale was printed on it. The pain was also assessed by three external evaluators using the sound, eye and movement meter (SEM) after the child was filmed in a video method using the camera of the Mi9 mobile device and the film was shown to them. The evaluation was conducted during three times: : First during the application of the substance, secondly before anesthesia, and thirdly, after the completion of anesthesia.
Results: There were no significant differences between cinnamon oil and benzocaine gel 20% in pain relief during local anesthetic needle insertion according to the SEM scale, and Wong Backer Faces modified by Al Monaqel scale.
Conclusions: cinnamon oil has a surface anesthetic effect similar to that of benzocaine gel 20%, it also has a pleasant taste
Les soft skills au cœur de la pédagogie interculturelle
No full textSoft skills have an essential role in intercultural pedagogy in the sense that they enable social interaction. Thus, they find their place in intercultural pedagogy because society is becoming more and more multicultural, but they also enable people to be equipped with the behavioural and human competences necessary to accept the Other in his or her difference. In this perspective, the integration of soft skills in intercultural pedagogy in university education cannot be neglected. However, as this term is still new in the Moroccan university system, the question that arises is: What exactly is the place of soft skills in intercultural pedagogy? This article will attempt to answer this question, focusing on the awareness of the importance of intercultural communication through soft skills, and then on the intercultural approach for a better integration of transversal competences in intercultural pedagogy
L’évaluation à l’ère du numérique : pratiques professionnelles et croyances sociales.
No full textPedagogies based on the use of new technologies appear as a solution to renovate traditional practices in a context marked by a break between the digital culture of young people and the types and modes of teaching. They are likely to motivate learners and enable them to acquire knowledge and develop new skills in complex and more authentic learning situations. In this work focused on information and communication technologies in teaching, we deal with the incorporation of new technologies into assessment practices. Indeed, the operation of the evaluation of learning is carried out, following the use of ICT, in new conditions thanks to new resources and new tools. Our objective is to verify the extent to which CTBT can improve the evaluation process and to highlight the added value of a digital evaluation. Thus, by adopting a mixed approach as a research methodology, the focus is on the state of digital evaluation practice, the difficulties encountered, the limits and the stakes of an evaluation in the digital age. This analysis also helps to understand how social beliefs influence the acceptance and integration of technologies into professional educational practices
La mise en visibilité pratiquée par/sur les réseaux socionumériques (RSN) : identité numérique et motivations d’usage Cas des jeunes artistes en développement d’Agadir en art visuel
No full textThe objective of this article is to present the results of a qualitative study conducted with around ten artists. The issue addressed is as follows: How are the practices of young artists affected by the visibility carried out by/on social networking sites (SNS)? We start from the premise that an artist\u27s relationship with SNS should be viewed not as a given, but as a construct subject to the influence of factors both intrinsic and extrinsic to the artist. Theoretically, we consider that the sociology of uses provides a suitable analytical framework to frame the normativity of this digital environment alongside the autonomy of the actor in defining his use(s). We particularly refer to De Certeau (1980) to understand the ways of doing and tinkering by, for and with these digital spaces
La construction de l\u27identité sociale à l\u27ère des médias numériques : l’exemple des vlogs
No full textIn the digital age, people connect and build their identities on online platforms. Social networks, blogs and virtual spaces provide places of expression for social identity. This new way of socializing online raises questions about the influence of digital media on identity formation. Indeed, many influencers use vlogs for personal expression, storytelling and social connection. The proliferation of vlogs in areas such as fashion, cooking, and more demonstrates a significant shift in our consumption of content online. In this regard, several influencers have chosen to transmit Moroccan identity through vlogs of Moroccan culinary content, by wearing traditional outfits and creating an authentically Moroccan atmosphere. This work aims to understand how these influencers represent their identity and their culture, and how this representation contributes to the construction and affirmation of their identity in a digital context
Exploring Sustainable Practices in Educational Buildings during the Project Lifecycle in Egypt
Get PDFSustainable construction approaches are essential for mitigating environmental concerns and enhancing energy efficiency in educational facilities. This research examines sustainability solutions in Egyptian educational institutions, concentrating on the design, building, and operating stages. The study combines quantitative and qualitative assessments from a survey of 66 industry experts, evaluating essential sustainability criteria like energy efficiency, water conservation, material sustainability, and operating expenses. Statistical methods, such as the Relative Importance Index (RII) and correlation analysis, were used to assess the relevance and interrelations among sustainability factors. The findings reveal that energy efficiency (RII: 0.82) and the promotion of health and well-being (RII: 0.82) are the most highly prioritized aspects, whilst rainwater collecting systems (RII: 0.47) are placed lowest. Obstacles like budgetary limitations, insufficient governmental assistance, and a lack of knowledge impede broad adoption. The report advocates for specific legislative interventions, stakeholder engagement initiatives, and technology integration as essential factors for improving sustainability in educational facilities. This study provides practical suggestions for policymakers, designers, and developers to enhance sustainability outcomes in educational buildings in Egypt by thoroughly assessing the difficulties and potential of sustainable construction