Circular thin walled structures have wide range of applications. This type of structure is generally exposed to different types of loads, but one of the most important types is a buckling. In this work, the phenomena of buckling was studied by using finite element analysis. The circular thin walled structure in this study is constructed from; cylindrical thin shell strengthen by longitudinal stringers, subjected to pure bending in one plane. In addition, Taguchi method was used to identify the optimum combination set of parameters for enhancement of the critical buckling load value, as well as to investigate the most effective parameter. The parameters that have been analyzed were; cylinder shell thickness, shape of stiffeners section and the number of stiffeners. Furthermore, to verify the contribution of parameters on buckling response, the analysis of variance technique (ANOVA) method was implemented, which gave the contribution weight as percentages. The analysis of results by these two methods showed that the more effective parameter on the critical buckling load was the thickness of cylinder’s shell and the lowest effective was the number of stiffeners The values of parameters that gave the best critical buckling load combination were: 1) the ratio of cylinder’s diameter to thickness of its shell was 133, 2) the ratio of the depth to thickness of stiffeners was1.6, and 3) the number of stiffeners was 12.
Novel has recently received the attention of readers and writers greatly, because of the role they play, and this indicates an important rule, which is whenever there is an art or creativity, there must be a respective criticism, and this criticism is certainly not less important than the author. So there are critics who have a prestigious literary position in the follow-up story development, and trying to describe the transformation of its elements. One of these critics is professor Fadhel Thamer, and who wants to approach one of the elements of the novel exploring, must stop on the visions of this critic about it , and that’s why we take the (character) element following the most important opinions of this critic about
... Show MoreBenthic invertebrates were used as bio- indicators to evaluate the pollution in -Diwania River . Five stations were selected for this purpose , extending from A1 -?? rtream to A1- Sadeer District downstream . The percentage of?ct uP?str?^ ? ?, oligochaeta to total benthic invertebrates were calculated . The population density of evaluation. 'I'he results Were ??? Tubificid worms without hair ehaetae was ©iso used IOBS(01igochaete Index of Sediment Bioindicati©n ), TUSP ? presented as indices Io (Tubificidae Species Percentage ) & degree of pollution Eo . IT was noticed that the 0 in??37.17 percentage of ©lig©chaeta to the total benthic invertebrates ranged between to 60.685 in station 3 , while the percentage ©f Tubificid w©rms t© ©
... Show MoreBackground: Skull secondary tumors are malignant bone tumors which are increasing in incidence.Objective: The objectives of this study were to present clinical features , asses the outcome of patients with secondary skull tumors ,characterize the MRI features, locations, and extent of secondary skull tumors to determine the frequency of the symptomatic disease.Type of the study: This is a prospective study.Methods: This is a prospective study from February 2000 to February 2008. The patients were selected from five neurosurgical centers and one oncology hospital in Baghdad/Iraq. The inclusion criteria were MRI study of the head(either as an initial radiological study or following head CT scan when secondary brain tumor is suspected , vis
... Show MoreThe research explores the confessional aspect in Audre Lorde's poem" Who Said It Was Simple ". Lorde depicts her personality under the stress of race, sex and sexuality. She discloses her own bitter experience concerning racism, sexism and sexuality in her poem to revive the retrospective truth of the Afro-Americans' life in the USA. This publicly manifestation of her personality and tribulation throughthe language ofpoetry has been regarded as the hallmark of confessional poetry.
In our research, we seek to shed a light on one of the most important and sensitive issues, namely, the Sufi influence in the Iraqi novel through the lame maqam of the novelist Jumaa Al-Lami, the Sufi discourse contains many semantic paradoxes between the text's apparent pronunciation and its interpretation of the format and the context that produced these patterns, and incited them, which concludes different results from the prevailing provisions and fixed ideas from the narrative text.The Arabic and Iraqi novel in particular became inspired by the power of Sufi discourse by talking about several Sufi figures by referring to it openly, or implicitly inspired by unauthorized concealment, in employing some of the ideas, or summoning
... Show MoreThe aim of this study is to shed light on the importance of biofuels as an alternative to conventional energy, in addition to the importance of preserving agricultural crops, which are the main source of this fuel, to maintain food security, especially in developing countries. The increase in global oil prices, in addition to the fear of global warming, are among the main factors that draw the world’s attention to searching for alternative sources of traditional energy, which are sustainable on the one hand, and on the other hand reduce carbon emissions. Therefore, the volume of global investment in renewable energy in general, and in liquid biofuels and biomass in particular, has increased. Global fears emerged that the excessive
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An experimental study was conducted for measuring the quality of surface finishing roughness using magnetic abrasive finishing technique (MAF) on brass plate which is very difficult to be polish by a conventional machining process where the cost is high and much more susceptible to surface damage as compared to other materials. Four operation parameters were studied, the gap between the work piece and the electromagnetic inductor, the current that generate the flux, the rotational Spindale speed and amount of abrasive powder size considering constant linear feed movement between machine head and workpiece. Adaptive Neuro fuzzy inference system (ANFIS) was implemented for evaluation of a serie
... Show MoreNaber and toning in the modern Arab poetry Mahmoud Darwish, a model