BEHAVIOR OF STEEL FIBER REINFORCED CONCRETE MADE WITH RECYCLED CONCRETE AGGREGATES: MATERIAL CHARACTERIZATION AND DEEP BEAM SHEAR RESPONSE

This research aims to examine the performance of concrete made with recycled concrete aggregates (RCAs) and steel fibers. It comprises material characterization tests, large-scale reinforced concrete (RC) deep beam tests, and numerical modeling. Material characterization test parameters included the RCA replacement percentage (30, 70, and 100%) and the steel fiber volume fraction (vf = 1, 2, and 3%). Fourteen large-scale deep beam numerical models with and without web openings made with 100% RCAs and steel fibers were developed and validated through a comparative analysis with test results. A numerical parametric study was conducted to investigate the effect of varying key parameters on the shear response. Plain concrete mixtures with RCAs exhibited inferior properties relative to those of a baseline mixture made with natural aggregates (NAs). The addition of steel fibers improved the hardened properties of the concrete mixtures with RCAs to an extent that exceeded the original value of some properties of their NA-based counterparts. A bilinear tensile softening law that can describe the post-cracking behavior of concrete made with RCAs and steel fibers was developed based on an inverse analysis of characterization test data. Experimental tests revealed that the addition of steel fibers in solid RC deep beams made with RCAs at vf of 1 and 2% restored 80 and 90% of the shear capacity, respectively, of a similar beam with minimum steel stirrups. The response of the RCA solid beam having vf of 3% outperformed that of the NA-based control beam with minimum steel stirrups. The shear strength gain of the RCA-based deep beams with openings due to the inclusion of steel fibers was in the range of 39 to 84%, whereas the use of conventional steel stirrups resulted in an 18% strength gain. The use of steel fibers at vf of 1% in the RCA-based beam with openings without steel stirrups was sufficient to restore 96% of the original shear capacity of the NA-based beam with minimum steel stirrups. Results of the numerical parametric study indicated that the shear strength gain caused by the addition of steel fibers at vf of 1 and 2% was higher in the deep beam models with the lower shear span-to-depth ratio (a/h) of 0.8, relative to that of their counterparts with a/h of 1.6. The effect of a/h on the shear strength gain of the solid deep beam models diminished at the higher vf of 3%. The solid deep beam models with a/h of 0.8 exhibited a shear strength gain of 78 to 108% due to the addition of steel fibers, whereas their counterparts with web openings experienced a reduced shear strength gain of 45 to 70%

Case 9 : A Knot of Contradictions: Systems of Intersectionality and Muslim LGBTQ+ Mental Health Programs

The case involves the protagonist, Yasmin Baytar, a queer Muslim woman who returns from the 2019 Women Deliver conference with the goal of implementing a community mental health program focusing on the LGBTQ+ Muslim population in Ottawa. She has extensive Sex- and Gender-Based Analysis Plus training and knowledge about intersectionality that she can use to develop a program that embraces true equality. However, she also needs to figure out how to obtain funding for her program and collaborate with different stakeholders while making sure she is keeping her population of interest involved and at the centre of her work. Students must use systems thinking approaches and recognize the importance of intersectionality when building the community mental health program. Incorporating an element of cultural sensitivity/competency into the program will show the students’ ability to critically think about an issue while taking intersecting identity factors into account. Furthermore, recognizing the importance of various levels of intervention, students will use the Social Ecological Model to ensure a multipronged, multileveled approach is included as the program is built. Students will be able to collaborate with a variety of experts/stakeholders to ensure the success of the intervention

Interpolation simple et efficace d'un bloc dans une image à partir de son contour

Dans certaines techniques de traitement et de compression, les images sont décomposées en blocs de pixels qui sont ensuite transformés par DCT. Par la suite, des blocs peuvent être abandonnés ou perdus et il faut les reconstituer, à partir de leur voisinage dans l'image. On montre qu'une interpolation exacte des blocs d'image peut être effectuée dans le domaine spatial, en utilisant la DCT. Les conditions d'existence d'une solution sont données et l'algorithme correspondant est optimisé, il nécessite 8 multiplications par pixel restitué. Des simulations montrent que l'interpolation exacte proposée présente de meilleures performances que d'autres méthodes, avec un moindre coût de calcul

Amputation primaire versus reconstruction par lambeau libre des fractures ouvertes de jambe : résultats fonctionnels et qualité de vie à long terme

Thèse présentée sous la forme d'une "thèse article"Introduction: The management of open tibial fractures remains a complex issue and continues to be an evolving debate in the field. The choice between early amputation or conservative treatment is not consensual. The main objective of this study was to compare the functional outcomes and quality of life of two groups of patients based on their initial treatment. The hypothesis was that early amputation provides better functional recovery and better quality of life compared to reconstruction.Materials and methods: All patients with Gustilo 3B or 3C open tibial fractures between January 2010 and December 2015 were included. Minimum follow-up of two years was necessary. Associated lesions, rate of complications, number of surgical procedures, rate of osteitis, initial hospital stay and the duration of follow-up were collected according to their initial treatment (primary amputation or reconstruction of the limb with free flap). Functional parameters such as chronic pain, walking distance, walking aids, work status, driving and physical agility were self-reported by patients as was the quality of life using the Short Form (SF-36). All these parameters were compared between the two groups.Results: Twenty-four patients were analyzed, thirteen in the free flap reconstruction group and eleven in the primary amputation group. Upon comparison, the rate of osteitis and number of surgical procedures carried out were significantly higher amongst the reconstruction patients group, along with follow-up time which was longer. Prolonged standing, hopping and running were better performed by the amputee patients. Other functional parameters such as pain, work life and driving were similar between the two groups. Both groups were also comparatively similar in terms of quality of life as well. However, amputee patients reported significantly better scores for physical activity and physical role functioning.Conclusion: Primary amputation in the management of severe trauma to the lower limbs appears to be a viable treatment option and must not be deemed as a failure. The decision must be made in a careful manner and should be multidisciplinary. At this point the two treatments are valid, however, the patient must be one of the main decision makers of which procedure to carry out after clear and fair information is given.Introduction : La prise en charge des fractures ouvertes de jambe reste complexe et continue à être un débat évolutif dans la littérature. Le choix entre une amputation précoce ou une attitude conservatrice n’est pas consensuel. L’objectif principal de cette étude était de comparer les résultats fonctionnels et la qualité de vie de deux groupes de patients en fonction de leur traitement initial. L’hypothèse était que l’amputation précoce offrait une meilleure récupération fonctionnelle et une meilleure qualité de vie que la reconstruction.Matériels et méthodes : Tous les patients qui ont eu une fracture ouverte de jambe Gustilo 3B, 3C entre Janvier 2010 et Décembre 2015 ont été inclus. Un suivi minimum de deux ans était nécessaire. Les paramètres cliniques tels que les lésions associées, le taux de complications, le nombre d’interventions chirurgicales, le taux d’infections ostéo-articulaires, la durée d’hospitalisation initiale et la durée de suivi ont été récupérés en fonction de leur traitement initial : amputation primaire ou reconstruction du membre par lambeau libre. Les paramètres fonctionnels tels que la douleur, le périmètre de marche, l’aide technique à la marche, la vie professionnelle, la conduite automobile et l’agilité physique ont été auto-reportés par les patients de même que la qualité de vie en utilisant l’échelle SF-36. Tous ces paramètres ont été comparés entre les deux groupes.Résultats : Vingt-quatre patients ont été analysés, treize dans le groupe reconstruction par lambeau libre et onze dans le groupe amputation primaire. Le taux d’infections ostéo-articulaires, le nombre d’interventions chirurgicales étaient significativement plus important chez les patients reconstruits. Le délai de suivi était plus long chez les patients reconstruits. La station debout prolongée, le fait de sautiller, courir étaient mieux réalisés par les patients amputés. Les autres paramètres fonctionnels comme la douleur, la vie professionnelle et la conduite automobile étaient comparables entre les deux groupes. Les deux groupes étaient comparables en matière de qualité de vie. Cependant, les patients amputés ont rapporté d’une manière significative de meilleurs scores pour l’activité physique et la limitation liée à l’état physique. Conclusion : L’amputation primaire dans le cadre de la prise en charge des traumatismes sévères des membres inférieurs semble être un traitement valide. Elle ne doit pas être considérée comme un échec thérapeutique. La décision doit être faite d’une manière prudente et après discussion pluridisciplinaire. A ce stade les deux choix se discutent, le patient doit être l’acteur principal de cette décision à l’issue d’une information claire et loyale

Demystifying Threshold Elliptic Curve Digital Signature Algorithm for MultiParty Applications

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Numerical Analysis of Concrete Deep Beams Reinforced with Glass Fiber-Reinforced Polymer Bars

This research aimed to generate data through a verified numerical model. The data were subsequently used to introduce a simplified analytical expression for the prediction of the shear strength of concrete deep beams reinforced with glass fiber-reinforced polymer (GFRP) reinforcing bars. A three-dimensional (3D) numerical simulation model for a large-scale GFRP-reinforced concrete deep beam (300 × 1200 × 5000 mm) was developed and validated against published experimental data. A parametric study was then conducted to examine the effects of key variables on the behavior and shear strength of GFRP-reinforced concrete deep beams. Eighteen 3D numerical models were developed to study the interaction between the concrete compressive strength (f’c), the shear span-to-depth ratio (a/h), the spacing between web reinforcement (s), and the shear strength. The a/h value was either 1.0 or 1.5. The values of f’c were 28, 37, and 50 MPa. The spacings between the web reinforcement, if present, were 100 and 200 mm. The results of the parametric study indicated that the shear strength of deep beam models increased almost linearly with an increase in f’c and a decrease in the stirrup spacing irrespective of the value of a/h. The strength reduction caused by increasing a/h was more pronounced for the beam models with the lower f’c and greater stirrup spacing. The simplified analytical expression introduced in the present study provided a reasonable prediction for the shear strength of GFRP-reinforced concrete deep beams

Shear Response of Recycled Aggregates Concrete Deep Beams Containing Steel Fibers and Web Openings

Replacement of natural aggregates (NAs) with recycled concrete aggregates (RCAs) in complex reinforced concrete (RC) structural elements, such as deep beams with openings, supports environmental sustainability in the construction industry. This research investigates the shear response of RC deep beams with openings made with 100% RCAs. It also examines the effectiveness of using steel fibers as a replacement to the minimum conventional steel stirrups in RCA-based deep beams with web openings. A total of seven RC deep beams with a shear span-to-depth ratio (a/h) of 0.8 were constructed and tested. A circular opening with an opening height-to-depth ratio (h0/h) of 0.3 was placed in the middle of each shear span. Test parameters included the type of the coarse aggregate (NAs and RCAs), steel fiber volume fraction (vf = 1, 2, and 3%), and presence of the minimum conventional steel stirrups. The deep beam specimens with web openings made with 100% RCAs exhibited 13 to 18% reductions in the shear capacity relative to those of their counterparts made with NAs. The inclusion of conventional steel stirrups in RC deep beams with openings was less effective in improving the shear response when 100% RCAs was used. The addition of steel fibers remarkably improved the shear response of the tested RCA-based beams. The gain in the shear capacity of the RCA-based beams caused by the inclusion of steel fibers was in the range of 39 to 84%, whereas the use of conventional steel stirrups resulted in 18% strength gain. The use of 1% steel fiber volume fraction in the RCA-based beam with openings without steel stirrups was sufficient to restore 96% of the original shear capacity of the NA-based beam with conventional steel stirrups. The shear capacities obtained from the tests were compared with predictions of published analytical models. The predicted-to-measured shear capacity was in the range of 0.71 to 1.49

Privacy preservation of genome data analysis using homomorphic encryption

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Numerical Modeling of Concrete Deep Beams Made with Recycled Aggregates and Steel Fibers

A bilinear tensile softening law that can describe the post-cracking behavior of concrete made with recycled concrete aggregates (RCAs) and steel fibers was developed based on an inverse analysis of characterization test data. Numerical simulation models were developed for large-scale concrete deep beams. The tensile softening laws along with characterization test results were used as input data in the analysis. The numerical deep beam models were validated through a comparative analysis with published experimental results. A parametric study was conducted to investigate the effect of varying the shear span-to-depth (a/h) ratio, steel fiber volume fraction (vf), and the presence of a web opening on the shear response. Results of the parametric study indicated that the shear strength gain caused by the addition of steel fibers at vf of 1 and 2% was higher in the deep beam models with a lower a/h of 0.8, relative to that of their counterparts with a/h of 1.6. The effect of a/h on the shear strength gain of the solid deep beam models diminished at the higher vf of 3%. The solid deep beam models with a/h of 0.8 exhibited a shear strength gain of 78 to 108% due to the addition of steel fibers, whereas their counterparts with the web opening experienced a reduced shear strength gain of 45 to 70%