This research presents a method for calculating stress ratio to predict fracture pressure gradient. It also, describes a correlation and list ideas about this correlation. Using the data collected from four wells, which are the deepest in southern Iraqi oil fields (3000 to 6000) m and belonged to four oil fields. These wells are passing through the following formations: Y, Su, G, N, Sa, Al, M, Ad, and B. A correlation method was applied to calculate fracture pressure gradient immediately in terms of both overburden and pore pressure gradient with an accurate results. Based on the results of our previous research , the data were used to calculate and plot the effective stresses. Many equations relating horizontal effective stress and vertica
... Show MoreRisk factors can be considered unique in construction projects, especially in tendering phase. This research is directed to recognize and evaluate the importance of critical risk factors in the tendering phase related to Iraq’s construction project. As a rule, construction projects are impacted by risk factors throughout the project life cycle; without identifying and allocating these risk factors, the project cannot succeed. In this paper, the open and closed questionnaires are used to categorize the critical risk factors in tendering phase. Research aims to recognize the factors that influence the success of tendering phase, to determine the correct response to the risk’s factors in this research article, (IBM, SPSS, V23) package has
... Show MoreRates of zinc consumption during cathodic protection of a copper pipeline carrying saline water were measured by the loss in weight technique. The study of sacrificial anode cathodic protection of short copper tube using zinc strip extended axially in the pipe revealed that : (i) The increase of zinc consumption with time of exposure (1-3 h's) at different flow rates (turbulent flow) (300-600 l/hr) while the temperature , solution concentration and the pH were fixed at 20ºC, 3.5%wt NaCl, and pH=8 respectively in absence and presence of bacteria.(ii)Increase of zinc consumption with flow rates (300-600 l/hr) at different temperatures (10-40ºC) while solution concentration and time of exposure were fixed at 3.5 %wt NaCl and 3hr's respective
... Show MoreIn 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
... Show MoreThis study is to investigate the possibility of using activated carbon prepared from Iraqi date-pits (ADP) which are produced from palm trees (Phoenix dactylifera L.) as low-cost reactive material in the permeable reactive barrier (PRB) for treating lead (Pb<sup>+2</sup>) from the contaminated groundwater, and then compare the results experimentally with other common reactive materials such as commercial activated carbon (CAC), zeolite pellets (ZP). Factors influencing sorption such as contact time, initial pH of the solution, sorbent dosage, agitation speed, and initial lead concentration has been studied. Two isotherm models were used for the description of sorption data (Langmuir and Freundlich). The maximum lead sorp
... Show MoreThis work was conducted to study the ability of locally prepared Zeolite NaY for the reduction of sulfur compounds from Iraqi natural gas by a continuous mode adsorption unit. Zeolite Y was hydrothermally synthesized using abundant kaolin clay as aluminum precursor. Characterization was made using chemical analysis, XRD and BET surface area. Results of the adsorption experiments showed that zeolite Y is an active adsorbent for removal H2S from natural gas and other gas streams. The effect of temperature was found inversely related to the removal efficiency. Increasing bed height was found to increase the removal efficiency at constant flow rate of natural gas. The adsorption capacity was evaluated and its maximum uptake was 5.345 mg H2S/g z
... Show MoreThis work presents experimental research using draped prestressed steel strands to improve the load-carrying capacity of prestressed concrete non-prismatic beams with multiple openings of various designs. The short-term deflection of non-prismatic prestressed concrete beams (NPCBs) flexural members under static loading were used to evaluate this improvement. Six simply supported (NPCBs) beams, five beams with openings, and one solid specimen used as a reference beam were all tested as part of the experiment. All of the beams were subjected to a monotonic midpoint load test. The configuration of the opening (quadrilateral or circular), as well as the depth of the chords, were the varia
The MTS-88. c trainer is a training system targeting students in the microprocessors course. It has a built in single-line assembler allowing the users to enter programs in assembly. It has the problem that long programs cannot be traced and tested efficiently. A simple error may cause all the code to be erased and the system to stop responding. Also, this system lacks the ability to be connected to the PC. The aim of this work is to modify the system to make it possible to be connected to the PC through the parallel port. This gives the capability to download long programs to the system after being developed in the PC. The 8255 Programmable Peripheral Interface available in the teaching system is interfaced to the parallel port and used as
... Show MoreDynamic loads highly influence soil properties and may cause real damage to structures and buildings. This article reports the experimental results from 24 tests to study the settlement of flexible and rigid raft foundation with different embedment depth rested on dense sandy soil. A small scale building model of dimension 200*200 mm and 320 mm in height was performed with reinforced concrete raft foundation of 10 mm thickness for flexible raft and 23 mm for rigid raft, The shaking table technique was used to simulate the seismic effect, the shaker was sat to give three different excitation frequencies 1,2,and3 Hz and displacement amplitude equal to 13 mm, the foundation was placed at
In this paper, the Active Suspension System (ASS) of road vehicles was investigated. In addition to the conventional stiffness and damper, the proposed ASS includes a fuzzy controller, a hydraulic actuator, and an LVDT position sensor. Furthermore, this paper presents a nonlinear model describing the operation of the hydraulic actuator as a part of the suspension system. Additionally, the detailed steps of the fuzzy controller design for such a system are introduced. A MATLAB/Simulink model was constructed to study the proposed ASS at different profiles of road irregularities. The results have shown that the proposed ASS has superior performance compared to the conventional Passive Suspension System (PSS), where the body displacemen
... Show MoreThis paper discusses a comparative study to relate parametric and non-parametric mode decomposition algorithms for response-only data. Three popular mode decomposition algorithms are included in this study: the Eigensystem Realization Algorithm with the Natural Excitation Technique (NExT-ERA) for the parametric algorithm, as well as the Principal Component Analysis (PCA) and the Independent Component Analysis (ICA) for the non-parametric algorithms. A comprehensive parametric study is provided for (i) different response types, (ii) excitation types, (iii) system damping, and (iv) sensor spatial resolution to compare the mode shapes and modal coordinates of using a 10-DOF building model. The mode decomposition results are also compared using
... Show MoreIn the context of normed space, Banach's fixed point theorem for mapping is studied in this paper. This idea is generalized in Banach's classical fixed-point theory. Fixed point theory explains many situations where maps provide great answers through an amazing combination of mathematical analysis. Picard- Lendell's theorem, Picard's theorem, implicit function theorem, and other results are created by other mathematicians later using this fixed-point theorem. We have come up with ideas that Banach's theorem can be used to easily deduce many well-known fixed-point theorems. Extending the Banach contraction principle to include metric space with modular spaces has been included in some recent research, the aim of study proves some pro
... Show MorePermanent deformation (rutting) of asphalt mixtures is one of the major forms of distress. Aggregate gradation is one of the most important factors affecting the permanent deformation of asphalt mixtures. Other variables are also important to understand their effects on the mixture such as temperature, binder content and compaction level. For this purpose 6 different aggregate gradations have been chosen and each one of them has been manufactured / tested with different variables. The results showed that at relatively low temperature there is little effect of aggregate packing on the permanent deformation. However, as the temperature increases the effect of gradation becomes apparent, in that the better the packing the better the resistance
... Show MoreReinforced concrete (RC) beams containing a longitudinal cavity have become an innovative development and advantage for economic purposes of light-weight members without largely affecting their resistance against the applied loads. This type of openings can also be used for maintenance purposes and usage space of communication lines, pipelines, etc. RC beams are primarily loaded in the plane of the members, which are two-dimensional in a plane stress state and the dominant structural behaviours include bending, shear, or combination of both. In the present study, six numerical models of RC beams with and without openings were simulated by using commercial finite element software ANSYS to evaluate the structural behaviours of those b
... Show MoreWater treatment plants play an important role in the purification and distribution of safe drinking water to the public. The present study focused on the performance assessment of the Al-Rasheed water treatment plant [ARWTP]. The main objectives of the assessment were to determine the efficiency of various plant units as well as the quality of inlet water from the Tigris River. Results obtained from the collected data indicated the presence of high concentrations of soluble nitrate and phosphate ions in the filtered water. The removal efficiency of alkalinity, EC, total hardness, SO4, Cl, NO3 and PO4 were found to be (+11.05%), (-0.67%), (-29.33%), (-2.64%), (-6.25%), (-32.13%), and (0%) respecti
... Show MoreDelays and disruption are a common issue in both community and personal building programs The problem exists all throughout the world, but it is particularly prevalent in Iraq, where millions of dollars are squandered each time as a outcome. Delays and interruptions may have serious consequences not just for Iraq's construction plans, but also for the country's economic and social status. While numerous studies have been conducted to investigate the factors driving delays and disruption in Iraqi construction projects, slight consideration has been given to by what means project management implements and approaches have affected the occurrence of project delays and disruption. After analyzing the crucial reasons for delays and instability in
... Show MoreSix 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.
... Show MoreThis research focuses on studying the effects of soil movement on the behavior of an existing pile driven in sandy soil. A physical model has been manufactured to investigate the effect of construction of an embankment adjacent to free head single pile driven in sand of dry unit weight of 13.5 kN/m3. The model pile of diameter (D) of 10 mm are tested under two conditions of loading: loaded axially and without load. The model piles are instrumented with strain gauges along the embedded length to measure strains resulting from the soil movement. The embankment loads are applied at distances of 2.5, 5, and 10D from the edge of the pile. The results obtained from the
The drones have become the focus of researchers’ attention because they enter into many details of life. The Tri-copter was chosen because it combines the advantages of the quadcopter in stability and manoeuvrability quickly. In this paper, the nonlinear Tri-copter model is entirely derived and applied three controllers; Proportional-Integral-Derivative (PID), Fractional Order PID (FOPID), and Nonlinear PID (NLPID). The tuning process for the controllers’ parameters had been tuned by using the Grey Wolf Optimization (GWO) algorithm. Then the results obtained had been compared. Where the improvement rate for the Tri-copter model of the nonlinear controller (NLPID) if compared with
Sub-threshold operation has received a lot of attention in limited performance applications.However, energy optimization of sub-threshold circuits should be performed with the concern of the performance limitation of such circuit. In this paper, a dual size design is proposed for energy minimization of sub-threshold CMOS circuits. The optimal downsizing factor is determined and assigned for some gates on the off-critical paths to minimize the energy at the maximum allowable performance. This assignment is performed using the proposed slack based genetic algorithm which is a heuristic-mixed evolutionary algorithm. Some gates are heuristically assigned to the original and the downsized design based on their slack time determined by static tim
... Show MoreThis paper describes flexural behavior of two spans continuous rectangular concrete beams reinforced with mild steel and partially prestressing strands, to evaluate using different prestressing level and prestressing area in continuous prestressed beams at serviceability and ultimate stages. Six continuous concrete beams with 4550 mm length reinforced with mild steel reinforcement and partially prestressed with two prestressing levels of (0.7fpy or 0.55fpy.) of and different amount of 12.7 mm diameter seven wire steel strand were used. Test results showed that the partially prestressed reinforced beams with higher prestressing level exhibited the narrowest crack width, smallest deflection and strain in both steel and concrete at ul
... Show MoreThe central marshes are one of the most important wetlands/ecosystems in the southern area of Iraq. This study evaluates the bed soil's mechanical, physical, and chemical properties at certain southern Iraqi central marshes sites. This was conducted to investigate their types and suitability for enhancing the agricultural reality of most field crops and for construction purposes. Soil samples were collected from 15 sites at 10-100 cm depth. Hence, numerous parameters were determined: index properties, unconfined compressive strength, direct shear strength, consolidation, texture, and sieve analysis, water content, specific gravity, dry density, permeability, pH, total soluble salts (TSS), organic materials (OM) and total
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