In practical engineering problems, uncertainty exists not only in external excitations but also in structural parameters. This study investigates the influence of structural geometry, elastic modulus, mass density, and section dimension uncertainty on the stochastic earthquake response of portal frames subjected to random ground motions. The North-South component of the El Centro earthquake in 1940 in California is selected as the ground excitation. Using the power spectral density function, the two-dimensional finite element model of the portal frame’s base motion is modified to account for random ground motions. A probabilistic study of the portal frame structure using stochastic finite elements utilizing Monte Carlo simulation is presented using the finite element program ABAQUS. The dynamic reliability and probability of failure of stochastic and deterministic structures based on the first-passage failure were examined and evaluated. The results revealed that the probability of failure increases due to the randomness of stiffness and mass of the structure. The influence of uncertain parameters on reliability analysis depends on the extent of variance in structural parameters.
BaCoxTixFe12-2xO19 (x=0.1, 0.5, 0.7, 0.9, 1.7) were prepared using powder technology technique . X-ray diffraction with diffractometer CuKα radiation analysis and Rietveld refinement of the samples were studied and showed a single phase of hexagonal structure with SP63/mmc space group . Lattice parameters, cell volume , crystallite size and x-ray density were determined .The hexagonal structure was represented by using PowderCell program showing the atomic positions of Co ,Ti, and Fe ions.
In this study, experimental and numerical applied of heat distribution due to pulsed Nd: YAG laser surface melting. Experimental side was consists of laser parameters are, pulse duration1.3
The researchers wanted to make a new azo imidazole as a follow-up to their previous work. The ligand 4-[(2-Amino-4-phenylazo)-methyl]-cyclohexane carboxylic acid as a derivative of trans-4-(aminomethyl) cyclohexane carboxylic acid diazonium salt, and synthesis a series of its chelate complexes with metalions, characterized these compounds using a variety technique, including elemental analysis, FTIR, LC-Mass, 1H-NMRand UV-Vis spectral process as well TGA, conductivity and magnetic quantifications. Analytical data showed that the Co (II) complex out to 1:1 metal-ligand ratio with square planner and tetrahedral geometry, respectively while 1:2 metal-ligand ratio in the Cu(II), Cr(III), Mn(II), Zn(II), Ru(III)and Rh(III)complexes
... Show MoreThe agricultural sector suffers from many risks and natural disasters, such as droughts and heavy rains that cause floods, as well as hail and agricultural pests, etc., that threaten agricultural activity and reduce it, which leads to the failure of farmers and peasants for fear of being subjected to continuous losses. Nevertheless, we notice almost complete reluctance to move towards agricultural insurance, due to the dependence of farmers on the government, which adopts the principle of compensation instead of agricultural insurance when natural disasters happen despite the difficulties and financial hardship as well as the suspicion of corruption that haunt the compensation process and this represents the most important problem for resea
... Show Morepatterns of utterance stress in discourse direct attention to specific themes and reactions, controlling the flow and coherence of conversation. this study examines the utterance stress in Steve Harvey's selected episodes from a phono-stylistic perspective. this study is hoped to improve understanding of linguistic mechanism in talk show communication, highlighting the importance of phonetic features in transmitting meaning and increasing broadcast conversation participation. the researcher concentrates on the types of focus functions of utterance stress of some episodes available on YouTube. to conduct the analysis, the researcher adopts (Carr, 2013; Davenport& Hannahs 2005) to analyze utterance stress and Leech and Short (2007
... Show MoreIn this paper, I highlight the bishops mentioned in the Bible in its sections
(The Old and New Testaments) where these books still retain the remaining remnant of the Bible
Issuing the prophets who preceded the mission of the Prophet Muhammad (peace and blessings of Allaah be upon him) and they must pray
And peace, as those bishops were mentioned in the Book of Formation through the recitation of the psalms
To Habakkuk, Malakhi, and Hajji.
As well as in the New Testament, which we see clearly in the four Angels: Matthew, Luke,
Disco, John.
Then the male lamented what was said of those bishops by expressing the eternal heavenly book (the Qur'an)
Al - Karim) as he focuses on this subject from multiple angles and exp
The influence of Cr3+ doping on the ground state properties of SrTiO 3 perovskite was evaluated using GGA-PBE approximation. Computational modeling results infered an agreement with the previously published literature. The modification of electronic structure and optical properties due to Cr3+ introducing into SrTiO 3 were investigated. Structural parameters assumed that Cr3+ doping alters the electronic structures of SrTiO 3 by shifting the conduction band through lower energies for the Sr and Ti sites. Besides, results showed that the band gap was reduced by approximately 50% when presenting one Cr3+ atom into the SrTiO 3 system and particularly positioned at Sr sites. Interestingly, substituting Ti site by Cr3+ led to eliminating the ban
... Show MoreUndoubtedly, Road Traffic Accidents (RTAs) are a major dilemma in term of mortality and morbidity facing the road users as well as the traffic and road authorities. Since 2002, the population in Iraq has increased by 49 percent and the number of vehicles by three folds. Consequently, these increases were unfortunately combined with rising the RTAs number, mortality and morbidity. Alongside the humanitarian tragedies, every year, there are considerable economic losses in Iraq lost due to the epidemic of RTAs. Given the necessity of understanding the contributory factors related to RTAs for the implementation by traffic and road authorities to improve the road safety, the necessity have been a rise for this research which focuses into
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