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.
In this paper, we studied the spark corona discharge in tap and distillited waters. The results show the shape of cone that generated on the tip of capillary tube is different with conductivity of liquids. The blue glow appears at the end of capillary tube and the drop extends into a cone. In addition, the conducitivity is affected on the relationship between the appearance of the blue glow discharge with the applied voltage. The size of the cone decreases with an increase in applied voltage. The cone diameter at the base of capillary tube oscillates with period approximately 1 Sec. this oscillates in the cone diameters is due to the change distance between the liquid electrode and the surface of liquid. The intensity of spark corona dis
... Show MoreLaser-Induced Breakdown Spectroscopy (LIBS) has been documented as an Atomic Emission Spectroscopy (AES) technique, utilising laser-induced plasma, in order to analyse elements in materials (gases, liquids and solid). The Nd:YAG laser passively Q-switched at 1064nm and 9ns pulse duration focused by convex lens with focal length 100 mm to generates power density 5.5×1012 Mw/mm2 with optical spectrum in the range 320-740 nm. Four soil samples were brought from different northern region of Iraq, northern region (Beiji, Sherkat, Serjnar and Zerkary).
The soil of the Northern region of Beige, Sherkat, Serjnar and Zarkary has abundant ratios of the elements P [0.08, 0.09, 0.18, 0.18] and Ca [0.61, 0.15, 0.92, 0.92] while it lack of Si [0.0
Small and Medium Enterprises (SMEs) in Iraq have experienced low performance due to the limited usage of accounting information systems (AIS) and the inability to exploit knowledge of management capabilities (KMC). These deficiencies have led to competitive pressures in the marketplace that have adversely affected their sales and production. This study investigates the role of AIS in terms of operation support, knowledge support, regulatory support, and the role of KMC, including knowledge acquisition, knowledge transfer, and knowledge utilized to enhance organizational performance in Iraqi SMEs. The target population was managers and owners in SMEs using AIS in Iraq’s cities. A non-probability purposive sampling technique was use
... Show MoreMarketing plays a role in the transfer of consumer desires through research, studies and satisfy the needs process, and with the technical development has evolved and marketing departments in the world of commerce has made great strides since the expansion of the trade deal, especially in light of spread of the Internet and the culture of use where he became a lot as individuals or institutions are dealings via electronic shopping . In all cases, we find that the consumer is important party, and that the legal rules did not leave the shopping process or contracting E without protection and I've dealt with so many studies through the civil protection for the consumer in electronic contracts legally with an analytical study of the
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Language is one of God’s blessings to human beings through which he
distingushed them from other creatures, then how if this language was arabic.
God honored this language and in which he descended his Gracious Boole
that gave it glory and magnificance, and made it an immortal revelation to the
arab nation in their poetry, oration, history and human tendency to the life of
knowledge, mind leadershipe, innovation and progress.
This study aimed at evaluating the arabic language come program for
the new teachers. The sample was of (25) participants who were shown a
questionaire consisting of (60) items distributed on (9) fields. Then, the data
was processed statisically by using preauency rate, Kai s
The present research aims to design an electronic system based on cloud computing to develop electronic tasks for students of the University of Mosul. Achieving this goal required designing an electronic system that includes all theoretical information, applied procedures, instructions, orders for computer programs, and identifying its effectiveness in developing Electronic tasks for students of the University of Mosul. Accordingly, the researchers formulated three hypotheses related to the cognitive and performance aspects of the electronic tasks. To verify the research hypotheses, a sample of (91) students is intentionally chosen from the research community, represented by the students of the college of education for humanities and col
... Show MoreThis research aims at studying and analyzing the creative research thinking of the educational staffs in private universities and colleges, and also the role of incentives, in its materialistic and moral sides in the development of such thinking and the pack of restraints which cause decline in interest level of the scientificresearch, and its weak role in the development of universities in Iraq, despite the interest of the Ministry of Higher Education and Scientific Research in Iraq in scientific research as part ofits academic and humanitarian targets.Based on study and analysis, and the using if some of statistical methods such as the Alpha Chronobaghcoefficient and the (T. Test)(F. Test),the research reached a number of conclusions.
... Show MoreBackground: Debonding orthodontic brackets and removal of residual bonding material from the enamel surface include critical steps that may cause enamel damage. The aim of the present study was to evaluate and compare the site of bond failure and enamel surface damage after debonding of three types of esthetic brackets (composite, ceramic, sapphire) bonded with light cure composite and resin-modified glass ionomer adhesive. Materials and methods: Seventy two maxillary premolars teeth were divided into three groups each group consisted of 24 teeth according to the type of brackets. Each group was subdivided into two subgroups (12 teeth for each) according to the bonding material that was used. After 7 days of bonding procedure, the brackets
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