One of the wellbore instability problems in vertical wells are breakouts in Zubair oilfield. Breakouts, if exceeds its critical limits will produce problems such as loss circulation which will add to the non-productive time (NPT) thus increasing loss in costs and in total revenues. In this paper, three of the available rock failure criteria (Mohr-Coulomb, Mogi-Coulomb and Modified-Lade) are used to study and predict the occurrence of the breakouts. It is found that there is an increase over the allowable breakout limit in breakout width in Tanuma shaly formation and it was predicted using Mohr-Coulomb criterion. An increase in the pore pressure was predicted in Tanuma shaly formation, thus; a new mud weight and casing programs are proposed to overcome such problems in the drilling operations in field developments plans.
Ti6Al4V alloy is widely used in aerospace and medical applications. It is classified as a difficult to machine material due to its low thermal conductivity and high chemical reactivity. In this study, hybrid intelligent models have been developed to predict surface roughness when end milling Ti6Al4V alloy with a Physical Vapor Deposition PVD coated tool under dry cutting conditions. Back propagation neural network (BPNN) has been hybridized with two heuristic optimization techniques, namely: gravitational search algorithm (GSA) and genetic algorithm (GA). Taguchi method was used with an L27 orthogonal array to generate 27 experiment runs. Design expert software was used to do analysis of variances (ANOVA). The experimental data were
... Show MoreIn this research an Artificial Neural Network (ANN) technique was applied for the prediction of Ryznar Index (RI) of the flowing water from WTPs in Al-Karakh side (left side) in Baghdad city for year 2013. Three models (ANN1, ANN2 and ANN3) have been developed and tested using data from Baghdad Mayoralty (Amanat Baghdad) including drinking water quality for the period 2004 to 2013. The results indicate that it is quite possible to use an artificial neural networks in predicting the stability index (RI) with a good degree of accuracy. Where ANN 2 model could be used to predict RI for the effluents from Al-Karakh, Al-Qadisiya and Al-Karama WTPs as the highest correlation coefficient were obtained 92.4, 82.9 and 79.1% respe
... Show MoreThe behavior and shear strength of full-scale (T-section) reinforced concrete deep beams, designed according to the strut-and-tie approach of ACI Code-19 specifications, with various large web openings were investigated in this paper. A total of 7 deep beam specimens with identical shear span-to-depth ratios have been tested under mid-span concentrated load applied monotonically until beam failure. The main variables studied were the effects of width and depth of the web openings on deep beam performance. Experimental data results were calibrated with the strut-and-tie approach, adopted by ACI 318-19 code for the design of deep beams. The provided strut-and-tie design model in ACI 318-19 code provision was assessed and found to be u
... Show MoreThirty uropathogenic E. coli isolates were isolated from hospitalized and non hospitalized patients, complaining of urinary tract infections, of Al-Kadhymia Teaching Hospital and subjected to tRNA extraction. A method of tRNA extraction was modified by adding sodium dodecyl sulfate (SDS) instead of urea. Polyacrylamide gel electrophoresis and two methods of staining, ethidium bromide staining and silver staining, as well as spectrophotometric detection were used.
Abstract Background: This in-vitro study was to evaluated bitewing radiograph and tactile examination for detection secondary caries adjacent to amalgam restorations. Material and method: Sixty primary extracted molars with class I and class II amalgam restorations were selected from children, and examined by bitewing radiographs were taken by using film holders and interpreted on a backlit screen without magnification. Then, we used tactile examination with blunt probe. Result: The result of this study showed that the best cut-off points for the sample were found by a Receiver Operator Characteristic (ROC) analysis, and the area under the ROC curve and the sensitivity, specificity and accuracy of the techniques were calculated for enamel (
... Show MoreStatistical studies are reported in this article for an active galactic nuclei sample of different type of active galaxies Seyferts 1, Seyferts 2, and Quasars. These sources have been selected from a Catalogue for bright X-ray galaxies. The name of this index is ROSAT Bright Source Catalogue (RBSC) and the NRAO VLA Sky Survey (NVSS). In this research, multi-wavelength observational bands Radio at 1.4 GHz, Optical at 4400 A0, and X-ray at energy 0.1-2.4 KeV have been adopted in this study. The behavior of flux density ratios has been studied , with respect to the absolute magnitude . Furthermore, the Seyfert1 and Seyfert 2 objects are combined in one group and the QSOs are collectest in another group. Also, it has been found that t
... Show MoreBackground: Denture lining materials are widely used in prosthodontic treatment and management of traumatized oral mucosa. A contaminated prosthesis can provide a source of cross-contamination between patients and dental personnel as well as a cause for denture stomatitis. Therefore, denture disinfection has been recommended as an essential procedure for maintenance of a healthy oral mucosa. This study investigated the effect of SOLO disinfectant solution on some properties of different denture lining materials. Materials and methods: Three different solutions were used in this study; SOLO disinfectant solution, sodium hypochlorite solution, and water on three types of acrylic denture lining materials; hot cure, cold cure, and soft acrylic
... Show More