168 research outputs found

    A nouvelle approach for predicting the shear cracking angle in RC and PC beams using artificial neural networks

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    The truss model for predicting shear resistance of reinforced concrete beams has usually been criticized because of its underestimation of the concrete shear strength especially for beams with low shear reinforcement. Two challengers are commonly encountered in any truss model and are responsible for its inaccurate shear strength prediction. First: the cracking angle is usually assumed empirically and second the shear contribution of the arching action is usually neglected. This research introduces a nouvelle approach, by using Artificial Neural Network (ANN) for accurately evaluating the shear cracking angle of reinforced and prestressed concrete beams. The model inputs include the beam geometry, concrete strength, the shear reinforcement ratio and the prestressing stress if any. ..

    Assessment of vehicular live load and load factors for design of short-span bridges according to the new Egyptian Code

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    AbstractThe new Egyptian Code (ECP-201:2012) introduces new vehicular live loads (VLL) and new load combinations for the design of roadway bridges. The new VLL and load combinations introduced in ECP-201:2012 are fundamentally different than those presented in previous versions of the code. The impact of these new loads and load combinations on the design of new bridges or the structural safety of the existing bridges that have been designed according to ECP-201:2003 or ECP-201:1993 has not been fully addressed for the different bridge deck systems. Three different bridge deck systems, i.e. concrete I-shaped girders, composite steel plate girders, and concrete box-girders with different spans were numerically modeled using two-dimensional grillage analogy. The bridge decks were analyzed under main gravity loads using VLL according to ECP-201:2012 and ECP-201:2003. The internal forces of individual load cases, total un-factored load combination, and total factored load combination of ECP-201:2012 and ECP-201:2003 were compared.The study shows that concrete box-girders designed according to ECP-201:2012 and ECP-201:2003 using the ultimate limit state method yield almost the same demand. Despite the increase in the VLL of ECP-201:2012, and consequently the live load forces, concrete I-shaped girder bridges will be subjected to less total factored internal forces in comparison to ECP-201:2003 This is attributed to the interaction between the live to dead loads ratio and the load combinations. Design of composite steel plate girder bridges according to ECP-201:2012 using the allowable stress design method yields over designed sections

    Feasibility of abdominoplasty with Cesarean section

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    Abdominoplasty is an esthetic surgical procedure that restores abdominal contouring. Repeated pregnancies combined with advancing maternal age usually lead to lower abdominal skin redundancy and excess fat accumulation. Delivery via Cesarean section adds weakness to the lower abdominal wall muscles and yields a lower transverse Cesarean scar. Some patients request whether abdominoplasty can be performed with Cesarean section in the same setting, to avoid a future surgery. This study was designed to evaluate the outcome of combined abdominoplasty with Cesarean section. The study included 50 pregnant women from September 2009 to June 2010 with an average follow-up period of 9 months. Nine patients (18%) developed wound infection; three of them (6%) developed wound dehiscence. Six patients (12%) developed lower abdominal skin necrosis; three of them (6%) were treated conservatively and healed by secondary intention, while surgical debridement and secondary sutures were needed in the other three patients (6%). Residual abdominal skin redundancy in nine patients (18%), outward bulging of the abdomen and lack of waist definition in 16 patients (32%), and outward bulging of the umbilicus in twelve patients (24%) were the reported unesthetic results. The results were compared with results of 80 abdominoplasties in nonpregnant women

    Pilot Experimental Tests on Punching Shear Strength of Flat Plates Reinforced with Stirrups Punching Shear Reinforcement

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    Flat plates are favor structure systems usually used in parking garages and high-rise buildings due to its simplicity for construction. However, flat plates have some inherent structural problems, due to high shear stress surrounding the supporting columns which cause a catastrophic brittle type of failure called "Punching Shear Failure". Several solutions are used to avoid punching shear failure, including the use of drop panels or punching shear reinforcement. The latter is being a more sophisticated solution from the structural ductility, the architectural and the economical point of view. This study aims at investigating the effect of stirrups as shear reinforcement in enhancing the punching strength of interior slab-column connections. A total of four full-scale interior slab-column connections were tested up to failure. All slabs had a side length of 1700 mm and 160 mm thickness with 200 mm x 200 mm square column. The test parameters were the presence of shear reinforcement and stirrups concentration around the supporting column. The test results showed that the distribution of stirrups over the critical punching shear zone was an efficient solution to enhance not only the punching shear capacity but also the ductility of the connection. Furthermore, the concentrating of stirrups shear reinforcement in the vicinity of the column for the tested slabs increases the punching shear capacity by 13 % compared to the uniform distribution at same amount of shear reinforcement

    Pilot Experimental Tests on Punching Shear Strength of Flat Plates Reinforced with Stirrups Punching Shear Reinforcement

    Get PDF
    Flat plates are favor structure systems usually used in parking garages and high-rise buildings due to its simplicity for construction. However, flat plates have some inherent structural problems, due to high shear stress surrounding the supporting columns which cause a catastrophic brittle type of failure called "Punching Shear Failure". Several solutions are used to avoid punching shear failure, including the use of drop panels or punching shear reinforcement. The latter is being a more sophisticated solution from the structural ductility, the architectural and the economical point of view. This study aims at investigating the effect of stirrups as shear reinforcement in enhancing the punching strength of interior slab-column connections. A total of four full-scale interior slab-column connections were tested up to failure. All slabs had a side length of 1700 mm and 160 mm thickness with 200 mm x 200 mm square column. The test parameters were the presence of shear reinforcement and stirrups concentration around the supporting column. The test results showed that the distribution of stirrups over the critical punching shear zone was an efficient solution to enhance not only the punching shear capacity but also the ductility of the connection. Furthermore, the concentrating of stirrups shear reinforcement in the vicinity of the column for the tested slabs increases the punching shear capacity by 13 % compared to the uniform distribution at same amount of shear reinforcement

    CONDA-PM -- A Systematic Review and Framework for Concept Drift Analysis in Process Mining

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    Business processes evolve over time to adapt to changing business environments. This requires continuous monitoring of business processes to gain insights into whether they conform to the intended design or deviate from it. The situation when a business process changes while being analysed is denoted as Concept Drift. Its analysis is concerned with studying how a business process changes, in terms of detecting and localising changes and studying the effects of the latter. Concept drift analysis is crucial to enable early detection and management of changes, that is, whether to promote a change to become part of an improved process, or to reject the change and make decisions to mitigate its effects. Despite its importance, there exists no comprehensive framework for analysing concept drift types, affected process perspectives, and granularity levels of a business process. This article proposes the CONcept Drift Analysis in Process Mining (CONDA-PM) framework describing phases and requirements of a concept drift analysis approach. CONDA-PM was derived from a Systematic Literature Review (SLR) of current approaches analysing concept drift. We apply the CONDA-PM framework on current approaches to concept drift analysis and evaluate their maturity. Applying CONDA-PM framework highlights areas where research is needed to complement existing efforts.Comment: 45 pages, 11 tables, 13 figure

    Bilateral Brachial Plexus Home Going Catheters After Digital Amputation for Patient With Upper Extremity Digital Gangrene

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    Peripheral nerve catheter placement is used to control surgical pain. Performing bilateral brachial plexus block with catheters is not frequently performed; and in our case sending patient home with bilateral brachial plexus catheters has not been reported up to our knowledge. Our patient is a 57 years old male patient presented with bilateral upper extremity digital gangrene on digits 2 through 4 on both sides with no thumb involvement. The plan was to do the surgery under sequential axillary blocks. On the day of surgery a right axillary brachial plexus block was performed under ultrasound guidance using 20 ml of 0.75% ropivacaine. Patient was taken to the OR and the right fingers amputation was carried out under mild sedation without problems. Left axillary brachial plexus block was then done as the surgeon was closing the right side, two hours after the first block was performed. The left axillary block was done also under ultrasound using 20 ml of 2% mepivacaine. The brachial plexus blocks were performed in a sequential manner. Surgery was unremarkable, and patient was transferred to post anesthetic care unit in stable condition. Over that first postoperative night, the patient complained of severe pain at the surgical sites with minimal pain relief with parentral opioids. We placed bilateral brachial plexus catheters (right axillary and left infra-clavicular brachial plexus catheters). Ropivacaine 0.2% infusion was started at 7 ml per hour basal rate only with no boluses on each side. The patient was discharged home with the catheters in place after receiving the appropriate education. On discharge both catheters were connected to a single ON-Q (I-flow Corporation, Lake Forest, CA) ball pump with a 750 ml reservoir using a Y connection and were set to deliver a fixed rate of 7 ml for each catheter. The brachial plexus catheters were removed by the patient on day 5 after surgery without any difficulty. Patient's postoperative course was otherwise unremarkable. We concluded that home going catheters are very effective in pain control postoperatively and they shorten the period of hospital stay

    A nouvelle approach for predicting the shear cracking angle in RC and PC beams using artificial neural networks

    Get PDF
    The truss model for predicting shear resistance of reinforced concrete beams has usually been criticized because of its underestimation of the concrete shear strength especially for beams with low shear reinforcement. Two challengers are commonly encountered in any truss model and are responsible for its inaccurate shear strength prediction. First: the cracking angle is usually assumed empirically and second the shear contribution of the arching action is usually neglected. This research introduces a nouvelle approach, by using Artificial Neural Network (ANN) for accurately evaluating the shear cracking angle of reinforced and prestressed concrete beams. The model inputs include the beam geometry, concrete strength, the shear reinforcement ratio and the prestressing stress if any. ..

    Problems issues on saving and processing of big data to ensure the accounting and preparation for exposure of electronic funds of archive institution in public electronic networks

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    Великі темпи зростання обсягу даних в інформаційних технологіях є невід’ємною складовою сучасного суспільства. Використання інформаційних технологій в архівній справі дозволяє підвищити ефективність надання державними архівними установами послуг, забезпечити популяризацію їхньої діяльності на новому якісному рівні шляхом застосування сучасних форм публікації та експонування архівних документів в електронному вигляді. Так, завдяки використанню інформаційних технологій користувачі Федерального архів у Німеччині мають можливість здійснити повнотекстовий пошук у колекції документів архіву, переглянути в зручній формі результати пошуку (зокрема у вигляді цифрованих зображень документів), а також, за потреби, замовити та сплатити певні додаткові послуги (напри клад, копію документа тощо). З аналогічною метою за підтримки ЮНЕСКО та Бібліотеки Конгресу США було створено вебсайт Світової цифрової бібліотеки. Метою дослідження є визначення належної програмної інфраструктури та об’єктної моделі організації даних, необхідних для забезпечення державного обліку документів Національного архівного фонду (облікової та вторинної архівної інформації) з метою створення якісної електронної експозиції та забезпечення користувачів можливістю вільного доступу до неї.Big data growth in information technology is an integral part of today's society. The use of information technologies in archival affairs allows to increase the efficiency of providing state archival institutions services, to ensure promotion of their activity at a new quality level by applying modern forms of publication and exhibiting archival documents in electronic form. So, thanks to using of information technology, users of the Federal Archives of Germany have the opportunity to search in full text search in the archive documents collection, to view in a comfortable form search results (in particular in the form of digital images of documents), and, if necessary, to order and pay for certain additional services (e.g. a copy of the document, etc.). For the same purpose, the World Digital Library website was created with the support of UNESCO and the Library of Congress. The purpose of the study is to determine the appropriate software infrastructure and an object model for organizing data needed to ensure state registration of documents of the National Archival Fund (accounting and secondary archival information) in order to create high-quality electronic exposure and provide users with free access to it
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