The Effect of Mechanical Combined Contact Stress with Buckling Load on the Stress Distribution in the Ball and SocketJoint Mechanism

The design of components subjected to contact stress as local compressive stress is important in engineering application especially in ball and socket Joining. Two kinds of contact stress are introduced in the ball and socket joint, the first is from normal contact while the other is from sliding contact. Although joining two long links (drive shaft in steering cars) will cause the effect of flexural and tensional buckling stress in hollow columns through the ball and socket ends on the failure condition of the joining mechanism. In this paper the consideration of the combined effect of buckling Load and contact stress on the ball and socket joints have been taken, epically on the stress distribution in the contact area. Different parameters have been taken in the design of joint. This is done by changing the angles for applied loads with the principle axis, the angle of contact between ball and socket and using different applied loads. <br />The problem has been solved using analytical solution for computing the critical loads and using these loads for calculating the stress distribution with finite element method using ANSYS 10. The numerical results have been compared with the experimental method using photo elasticity pattern which shows good agreement between experimental and simulation results

Behavior of High Strength Hybrid Reinforcement Concrete Beams

Six proposed simply supported high strength-steel fiber reinforced concrete (HS-SFRC) beams reinforced with FRP (fiber reinforced polymer) rebars were numerically tested by finite element method using ABAQUS software to investigate their behavior under the flexural failure. The beams were divided into two groups depending on their cross sectional shape. Group A consisted of four trapezoidal beams with dimensions of (height 200 mm, top width 250 mm, and bottom width 125 mm), while group B consisted of two rectangular beams with dimensions of (125 ×200) mm. All specimens have same total length of 1500 mm, and they were also considered to be made of same high strength concrete designed material with 1% volume fraction of steel fiber. Different types and ratios of FRP rebar were used to reinforce these test beams. The study’s principle variables were the amount and type of flexural reinforcement (glass FRP and basalt FRP) and beam cross-sectional shape (rectangular and trapezoidal). The load-deflection behavior and ultimate load capacity of the beams were studied and compared with one another under flexural test with symmetrical two-point loading. The results show that increasing the reinforcement ratio resulted in higher post cracking flexural stiffness, and higher residual strength, as well as caused an increase in the first cracking load and ultimate load capacity ranged from 3 to 16.9%, and 4.6 to 7.3% respectively. When the GFRP rebars replaced by BFRP, the overall beams flexural performance showed outstanding improvements. Moreover the results indicate that increasing the top width of the beam cross section led to a significant enhancement in the first crack load ranged from 16 to 32.4%, also a remarkable increases in the ultimate load capacity in the range of 35.5 to 35.8% were indicated in the trapezoidal beams compared to rectangular beams. However the results show that the deflections were similar and were approximately 1.07–1.54 mm for all test beams. It is worth noting that the general flexural behavior of all the test beams indicated a ductile behavior with a gradual reduction in strength and high residual strength pre to failure due to proposing steel fiber presence

Influence of limestone filler and of the size of the aggregates on DEF

This experimental study aims to determine the effect of limestone filler on concrete expansion due to delayed ettringite formation (DEF). Different mortars made with different sizes and percentages of limestone filler and Portland cement CEM I 52.5N are conserved in water. The expansion of the specimens is measured. Results show that DEF is not inhibited by limestone filler. The kinetics and the amplitude of the swelling depend on the size of the limestone filler. The volume fraction of aggregates changes only the kinetics: the relation between swelling and water uptake depends only on the size of the aggregates.Comment: 16 pages, 9 figures, 4 table

Asymmetric Cascaded Multilevel Inverter with Unequal Dc Sources using SPWM and MSVPWM Topologies

This paper introduces the modeling design and simulation of seven and thirteen levels cascaded asymmetric multilevel inverter (MLI) with reduced number of switches.  MLI is the most efficient energy converters which are essentially appropriated for high power applications with decrease total harmonics distortion (THD). MLI doesn't only get high power in the output but it is also utilized in renewable energy resources such as fuel cells, wind and photovoltaic cells. This paper principally focuses on a hybrid cascaded MLI with two and three unequal dc supplies which decreases the number of semiconductor power switches. Sinusoidal PWM (SPWM) and modified space vector PWM (MSVPWM) techniques are used to improve an ac output with reduced THD. The gating pulses for seven and thirteen level hybrid cascaded converter using SPWM and MSVPWM techniques are introduced. The results of these proposed modulation strategies reduce the percentage magnitude of THD. The performance of the proposed SPWM and MSVPWM topologies are verified using seven and thirteen levels cascaded asymmetric MLI via simulink/matlab. Keywords: Sinusoidal Pulse Width Modulation (SPWM), Modified Space Vector Pulse Width Modulation (MSVPWM), Multilevel Inverter (MLI), Total Harmonics Distortion (THD)

Some Water Properties and Suitability of Shatt Al-Hilla in Babil Governorate, Iraq

يعتبر شط الحلة في محافظة بابل احد المصادر الرئيسية للماء في مدينة الحلة ويستخدم لاغراض مختلفة. الهدف من البحث هو دراسة نوعية المياه السطحية ضمن منطقة الدراسة ومدى ملائمتها للاغراض المذكورة سابقا ,كذلك تصنيف نوعية المياه. تضمنت الدراسة تحليل 9 نماذج للمياه السطحية على طول شط الحلة, من العناصر الكيميائية التي تم تحليلها (Ca2+, Mg2+, Na+, K+) &nbsp;و (HCO3=, CO3=, SO42-, Cl-) ومن العناصر الاخرى (NO3=) و(PO43-), وكذلك قياس العسرة الكلية و التوصيلية الكهربائية والاملاح الكلية الذائبة . اظهرت نتائج مؤشر نوعية المياه ان المياه تراوحت بين الجيد الى الممتاز, مخطط بابيبر اظهر نوع المياه من النوع c &nbsp;والذي يدل المياه ذات اصل قلوي ارضي مع زيادة القلوية بزيادة الكبريتات والكلورديات. تم قياس ملائمة المياه للاغراض المختلفة وذلك بمقارنتها مع مقياس منظمة الصحة العالمية ومع المقياس العراقي وقد اظهرت نتائج المقارنة ان المياه ملائمة للاغراض والاستخدامات المختلفة ( لغرض الشرب, الري, للمواشي, لغرض البناء) عدا عن استخدامها للاغراض الصناعية وذلك لزيادة تراكيز العناصر الكيميائية عن الحد المسموح به.Shatt Al Hilla River within Babylon Governorate is one of the main water resources in Hilla citys which uses for different purposes. The object of this paper is studying the quality of surface water resources in the study area besides determining its suitability for different anthropogenic uses and classifying the water type. This study included the analysis of (9) surface water samples along the river, those analyses included chemical parameters such as (Ca2+, Mg2+, Na+, K+) and main anions (HCO3=, CO3=, SO42-, Cl-) and other important anions, i.e. Nitrate (NO3=) and (PO43-), Total Hardness, Electrical Conductivity, Total Dissolved Salts. Results of Water quality index ranged from good to excellent type, Piper Diagram referred to water of class (c) which means the water of Earth Alkaline source with increasing in portions of Alakalis under prevailing sulfate and Chloride. Water suitability conducted by comparing with World health organization standers and Iraqi standers, the result of water suitable for different uses (drinking, irrigation, livestock, building purposes) except for industrial uses because of the high concentrations of the chemical parameters

EVOLVING ROLE OF CAR T-CELL IN CANCER IMMUNOTHERAPY

Safety profiles of newly developed anti-cancer therapies is the main goal for efficient treatments to improve survival rates. Therefore, continuous efforts carried out to develop a therapeutic strategy with better outcomes. The concept of immune-oncology, which utilizes and enhances the capacity of human immune system was developed as an eventual opportunity to enhance remissions and limit the relaps of the disease. Later progression of cellular immunetherapies involve the introduction of genetically engineered T cells having chimeric antigen receptors (CARs) that embraced an antibody-derived antigen recognition domain connected to an internal T-cell signaling domain, so can recognize their targets with high degree of tumor selectivity. This approach showed vigorous antitumor outcomes and full recovery in end-stage patients suffering from liquid cancers as leukemia and lymphoma. However, still there is a challenge for bringing genetically modified T-cell immunotherapy to many patients with different tumor types including solid tumor. On other hand, studies indicated the potential to broaden T-cell–based therapies and foster for other possible applications beyond oncology as organ transplantation and autoimmunity. Therefore, this review aimed to illustrate the clinical applications, challenges, and approaches for more efficient clinical employment of CAR T cell therapies

Modernism and after: Modern Arabic literary theory from literary criticism to cultural critique.

This thesis aims to provide the interested reader with a critical account of far-reaching changes in modem Arabic literary theory, approximately since the 1970s, in the light of an ascending paradigm in motion, and of the tendency by subsequent critics and commentators to view literary criticism in terms of a self-elaborating category morphing into cultural critique. The first part focuses on interdisciplinary problems confronting Arab critics in their attempt "to modernize but not to westernize", and also provides a comparative treatment of the terms, concepts and definitions used in the context of an ever-growing Arabic literary canon, along with consideration of how these relate to European modernist thought and of the controversies surrounding them among Arab critics. The second part explores some distinguishable morphological markers whose deployment involves a more or less radical distinction between, on the one hand, renovationist assumptions of cultural change as an uninterrupted process of historical continuity, and, on the other, innovationist assumptions based on discontinuity. The first of these modernizing models, involving revivalist ideas from the age of al-Nahdah, laid the foundation for a double dependency, on the past, serving to compensate, through remembering and reviving, for lack of creativity; and on the European-American West, serving to compensate, through intellectual and technical adaptation and borrowing, for the failure to invent and innovate. However, it is the second, counter-revivalist model that has assumed pride of place through the work of various poets, theorists and critics considered here. By the end of the eighties a self-generating, self-referential modernist theory had become the dominant critique. The third part proffers the case for a new paradigm. Drawing on the arguments and views of numerous scholars, the emphasis here is that "difference" establishes a distinctive mode of autonomy vis-a-vis Western Eurocentric theory

Experimental Study of Behaviour of Reactive Powder Concrete Strengthening by NSM-CFRP Corbels

The research contain an experimental examination for the behaviour of reactive powder concrete corbels, strengthened with  varying orientation of  Near Surface Mounted Carbon Fiber Reinforcement Polymers (CFRP) strips. Six reactive powder concrete corbels were tested. Divided into two groups, each group contain three specimens, one of them without strengthening takes as control corbel specimen, two corbels in each group strengthened by inclined and horizontal near surface mounted carbon fiber reinforced polymer (NSM-CFRP) stripes, other variable was the shear span to the effective depth ratio (a/d) to study the influences of those variables on the ultimate strength carrying capacity, cracking pattern, cracking load, vertical deflection, failure modes. The results showed an important improvement in the behaviour and load capacity of strengthened reinforced RPC corbels in addition to enhancing the stiffness of corbels. For group A where a/d =0.65, the percentages of increase in load failure were about (10.3% - 15.45%) for inclined and horizontal strengthening respectively, and for group B where  a/d =0.4, the percentages of  increase in load failure were about  (7.1% - 14.6%) for inclined and horizontal strengthening respectively

Étude du risque de développement d'une réaction sulfatique interne et de ses conséquences dans les bétons de structure des ouvrages nucléaires

La réaction sulfatique interne (RSI) dans les ouvrages en béton est une pathologie susceptible de se développer lorsque des conditions particulières portant sur la composition du béton, les conditions thermiques au jeune âge et l'environnement sont réunies. Ce phénomène est attribué à la formation d'ettringite différée qui provoque un gonflement du matériau et une fissuration dans la structure. Deux types de béton sont concernés par cette pathologie : les bétons préfabriqués traités thermiquement et les bétons coulés en place dans les pièces massives. Bien que largement étudiée depuis une dizaine d'années, la RSI n'est pas à ce jour parfaitement connue du fait de la complexité du phénomène au niveau des mécanismes mis en jeu, des paramètres influents et de ses conséquences tant à l'échelle microscopique qu'à l'échelle de l'ouvrage. Ce travail vise donc à apporter des éléments de réponse à plusieurs interrogations concernant cette pathologie, en se focalisant sur l'étude de l'impact de certains facteurs intervenant lors de la réaction et sur l'application nucléaire. De nombreuses études expérimentales ont été ainsi mises en œuvre. Une large étude est consacrée à évaluer le risque de développement de la RSI dans une enceinte de confinement d'une centrale nucléaire, du fait de la présence de structures massives dans ce type d'ouvrages. Ces travaux ont permis de mettre en évidence dans quelle mesure la pathologie influe sur les caractéristiques mécaniques et sur les propriétés de transfert du béton, et ainsi de vérifier si les exigences de sûreté attendues par ces structures sont mises en cause. Ensuite, nous nous sommes intéressés à étudier l'impact de l'hygrométrie du béton sur le développement de la RSI. Nous avons pu identifier le couplage qui existe entre l'humidité environnante et le gonflement. Le rôle joué par la lixiviation des alcalins a été également mis en évidence. Des suivis des propriétés de transfert ont été menés et confrontés aux gonflements observés. Enfin, nous nous sommes intéressés à caractériser le rôle joué par le squelette granulaire sur la cinétique et l'amplitude du gonflement par RSI. Les paramètres étudiés concernent la taille et la fraction volumique des inclusions granulaires. De plus, un exemple d'application d'une modélisation numérique mésoscopique du gonflement est proposéDelayed ettringite formation (DEF) in concrete structures is a pathology that can develop when special conditions on the concrete composition, the thermal conditions at the young age and the environment are met. This phenomenon provokes swelling of the material and cracking in the structure. It affects two types of concrete : the concrete heat-treated and the concrete cast in place in massive parts. Although many studies were done before in order to better understand this pathology, the DEF is still not well known. This is due to its complex mechanism, the influential parameters and its consequences on microscopic and structural scales. For that purpose, the thesis work was designed in order to better understand this pathology. Experimental studies were done to evaluate the impact of certain factors during the reaction, by focusing on nuclear application. An important part of this study was dedicated to assess the risk of DEF development in a nuclear power plant, and to understand how this pathology affects the mechanical characteristics and transfer properties of the concrete. Then, we have studied the impact of the hygrometry on the development of DEF. This has lead to identify a relation between environmental humidity and swelling. We have also examined the role of alkali leaching. A follow up study of the transfer properties was also done and was confronted to the observed swelling. Finally, we were interested in the characterization of the aggregates effect on the kinetics and the amplitude of DEF swelling. So, we have examined the parameters related to the size and the volume fraction of granular inclusions. Furthermore, an application of a mesoscopic numerical modeling of swelling is proposedPARIS-EST-Université (770839901) / SudocSudocFranceF

Knowledge about stroke among adults in Sharjah, United Arab Emirates

Background: In UAE, stroke is the second leading cause of disability after RTA, where annually 8,000 to 10,000 patients get a stroke. Our aim is to identify the knowledge levels of stroke among Sharjah’s adult citizens.Methods: Using self-administered questionnaires, in a cross-sectional design, a non-probability convenience sampling method was used to enrol subjects. Eligible subjects were above 18 years of age, comprehended Arabic or English, and are currently residing in Sharjah. The questionnaire was 17 questions structured in 5 sections which included: demographics, general knowledge, knowledge of signs and symptoms, risk factors, and appropriate response towards stroke. SPSS V.22 was used to analyse the data. Percentages, means, and ANOVA were used. A P-value less than 0.05 was considered to be statistically significant.Results: The study included 426 subjects, mean age was 35.1 years, 65.2% were females. 51.8% of the subjects claimed they know what stroke is, out of whom 24.3% provided incorrect descriptions. The mean knowledge level of signs and symptoms was 55.4%, and of risk factors was 40.6%. Visual disturbance was the least identified of the five signs and symptoms (38.0%). Female gender, African American race, and age above 60, were the least identified of the 8 risk factors (4.7%, 3.5%, 19.8% respectively). Better knowledge was associated with increased age and higher education. Conclusion: The majority of the sample showed an average to low level of knowledge. Such results indicate the importance of implementing more awareness programs that target younger age groups in the community