86 research outputs found

    Fibre composite railway sleeper design by using FE approach and optimization techniques

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    This research work aims to develop an optimal design using Finite Element (FE) and Genetic Algorithm (GA) methods to replace the traditional concrete and timber material by a Synthetic Polyurethane fibre glass composite material in railway sleepers. The conventional timber railway sleeper technology is associated with several technical problems related to its durability and ability to resist cutting and abrading action of the bearing plate. The use of pre-stress concrete sleeper in railway industry has many disadvantages related to the concrete material behaviour to resist dynamic stress that may lead to a significant mechanical damage with feasible fissures and cracks. Scientific researchers have recently developed a new composite material such as Glass Fibre Reinforced Polyurethane (GFRP) foam to replace the conventional one. The mechanical properties of these materials are reliable enough to help solving structural problems such as durability, light weight, long life span (50-60 years), less water absorption, provide electric insulation, excellent resistance of fatigue and ability to recycle. This paper suggests appropriate sleeper design to reduce the volume of the material. The design optimization shows that the sleeper length is more sensitive to the loading type than the other parameters

    Finite element analysis of fibre composite sandwich panel

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    This research work aims to understand the behaviour of fibre composite sandwich panel by using nonlinear Finite Element (FE) method. The original FRP sandwich panel is associated with waste of materials usage related to its ability to resist the external load and stay in the working load serviceability. The experimental analysis was done by CEEFC in the University of Southern Queensland and it showed that the failure load is (5-10) times the working load recommended by EUROCOMP. The analysis of composite FRP panel using 3D solid Finite Element and shell element shows a relatively accurate simulation for the behaviour of the FRP panel compare to the experimental results. The objective of this research is to verify the behaviour of FRP sandwich panel by using finite element methods. The numerical finite element model using traditional available ABAQUS software was developed to simulate the structural behaviour of FRP panel

    Aberrant Presentation of the Gallbladder During Laparoscopic Cholecystectomy

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    A left aberrant gallbladder is a rare presentation that requires awareness of biliary anatomy and selective use of intraoperative cholangiography to assist in safe laparoscopic gallbladder resection

    العشائر والسلطة في مدينة حلب

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    Throughout the war years in Aleppo, 2012-2016, many tribesmen from the Bab al-Neirab neighbourhood established pro-regime militias that fought against the opposition factions controlling the eastern part of the city. With a strengthened connection to the regime and its Iranian backers, the leaders of these militias enhanced their political, economic and social positions both during and after the fighting had ended in the city.Abstract: خلال الحرب المدمرة التي شهدتها مدينة حلب بين ٢٠١٢ و٢٠١٦، قام بعض أبناء العشائر في حي باب النيرب بتأسيس ميليشيات مسلحة موالية للنظام والقتال ضد فصائل المعارضة التي كانت تسيطر حينذاك على الأحياء الشرقية من المدينة. وقد أتاحت تلك الميليشيات لقادتها أو مؤسِّسيها توطيد صلاتهم بالنظام أو بحلفائه الإيرانيين، ومن ثم تعزيز مكانتهم ومكاسبهم على المستويات السياسية والاقتصادية والاجتماعية، حتى بعد انتهاء العمليات القتالية في المدينة

    إعادة بناء شبكات النظام السوري في مدينة دير الزور: من هم الفاعلون المحليون؟

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    This paper analyses the transformations that have taken place within Deir Ez-Zor city’s local elite since the outbreak of the revolution in Syria. It examines the various effects that the conflict has had on the roles and nature of this elite and focuses especially on how the war economy has shaped.تستعرض هذه الورقة تحولات النخب المحلية في مدينة دير الزور بعد اندلاع الثورة في سورية. وترصد الورقة الآثار المختلفة التي خلفها الصراع في أدوار وطبيعة النخب، وترصد أثر اقتصاد الحرب على وجه الخصوص في صعود فاعلين رئيسيين جاؤوا عبر مسارات مختلفة، احتلوا اليوم مواقع هامة إلى جانب فاعلين سابقين وتكنوقراط ضمن شبكات السيطرة المحلية التي يعيد نظام الأسد بنائها على صعد مختلفة، سياسية، وإدارية، واقتصادية في مدينة دير الزور

    الجمعيات غير الحكومية في مدينة حلب: تحت قبضة النظام وفي خدمته

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    Non-governmental organisations in the city of Aleppo have undergone deep transformations since 2011. Relying on various tools, the regime ensures its domination over registered local NGOs and their international backers, primarily to serve its own interests and those of its war-born networks and only marginally to address the needs of the local population. Based on qualitative interviews with local actors and a sample of 17 local NGOs, this paper examines the role of the biggest charity and development associations which operate in the fields of relief aid, healthcare, education and care for orphans and the disabled. The paper also analyses the different levels and mechanisms of intervention used by the regime in the NGO sector.بالاعتماد على أدوات متنوعة، يسيطر النظام السوري على قطاع الجمعيات غير الحكومية في مدينة حلب، ويوجّه أعمالها بما يخدم مصالحه الاقتصادية والاجتماعية ومصالح الشبكات التابعة له قبل مصالح السكان. تشرح هذه الورقة آليّات تدخل النظام في هذا القطاع، والدور الذي تؤديه الجمعيات الخيرية والتنموية في حياة المحتاجين لخدماتها، في المدينة التي مرت بحرب مدمرة وتمر اليوم بأزمة اقتصادية متصاعدة خلقت المزيد من مستحقي العون والمساعدة

    Carcinoma of the Tail of the Pancreas Presenting As Acute Abdomen

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    Context Large bowel obstruction with perforation is an anomalous presentation of pancreatic tail carcinoma. Pancreatic cancer is often difficult to diagnose clinically and is especially furtive when it is located in the tail of the pancreas. Case report We describe a patient who presented with large bowel obstruction due to splenic flexure mass which proved to be due to pancreatic mucinous adenocarcinoma. Conclusions Pancreatic adenocarcinoma can rarely have the same presentation as colon cancer, and should therefore be considered in the differential diagnosis of large bowel obstruction

    Laparoscopic Management of Sigmoidorectal Intussusception

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    This case of sigmoidorectal intussusception was caused by a large tubovillous adenoma and managed with laparoscopic sigmoidectomy

    MERS coronavirus outbreak: Implications for emerging viral infections

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    In September 2012, a novel coronavirus was isolated from a patient who died in Saudi Arabia after presenting with acute respiratory distress and acute kidney injury. Analysis revealed the disease to be due to a novel virus which was named Middle East Respiratory Coronavirus (MERS-CoV). There have been several MERS-CoV hospital outbreaks in KSA, continuing to the present day, and the disease has a mortality rate in excess of 35%. Since 2012, the World Health Organization has been informed of 2220 laboratory-confirmed cases resulting in at least 790 deaths. Cases have since arisen in 27 countries, including an outbreak in the Republic of Korea in 2015 in which 36 people died, but more than 80% of cases have occurred in Saudi Arabia.. Human-to-human transmission of MERS-CoV, particularly in healthcare settings, initially caused a ‘media panic’, however human-to-human transmission appears to require close contact and thus far the virus has not achieved epidemic potential. Zoonotic transmission is of significant importance and evidence is growing implicating the dromedary camel as the major animal host in spread of disease to humans. MERS-CoV is now included on the WHO list of priority blueprint diseases for which there which is an urgent need for accelerated research and development as they have the potential to cause a public health emergency while there is an absence of efficacious drugs and/or vaccines. In this review we highlight epidemiological, clinical, and infection control aspects of MERS-CoV as informed by the Saudi experience. Attention is given to recommended treatments and progress towards vaccine development
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