Understanding sedimentation behavior and its transport capacity in the Tigris River is of significant importance owing to the detrimental consequences caused by it. This study investigates the sediment amounts transported along the reach of the Tigris River in Baghdad. The CCHE2D model which is a common tool developed by the National Center for Computational Hydrological Science and Engineering (NCCHE) was applied to investigate the flow pattern and sediment amounts within 7 km reach. The model was initially calibrated and validated under steady-state conditions at the Sarai gauging station (upstream) and its performance was evaluated around the Abu Nawas water treatment plant (downstream). The result shows that the water surfac
... Show MoreThis paper aims to decide the best parameter estimation methods for the parameters of the Gumbel type-I distribution under the type-II censorship scheme. For this purpose, classical and Bayesian parameter estimation procedures are considered. The maximum likelihood estimators are used for the classical parameter estimation procedure. The asymptotic distributions of these estimators are also derived. It is not possible to obtain explicit solutions of Bayesian estimators. Therefore, Markov Chain Monte Carlo, and Lindley techniques are taken into account to estimate the unknown parameters. In Bayesian analysis, it is very important to determine an appropriate combination of a prior distribution and a loss function. Therefore, two different
... Show MoreIn this study, we used Bayesian method to estimate scale parameter for the normal distribution. By considering three different prior distributions such as the square root inverted gamma (SRIG) distribution and the non-informative prior distribution and the natural conjugate family of priors. The Bayesian estimation based on squared error loss function, and compared it with the classical estimation methods to estimate the scale parameter for the normal distribution, such as the maximum likelihood estimation and th
... Show MoreSamples from tap water were chosen to be examined as one of the possible modes of G. lamblia and other parasites transmission. 144 domestic filter units were randomly distributed to houses in Baghdad in Al-Sadr City and surrounding regions then the suspended materials were examined microscopically by direct wet mount after centrifugal sedimentation method, and after staining with modified Ziehl-Neelsen (acid fast) stain. The results showed that 5/144 (3.47%) samples contained G. lamblia cysts, 3/144 (2.08%) contained E. histolytica/E. dispar cyst, while each of Cryptosporidium spp. and Cyclospora cayetanensis oocysts were observed in two samples (1.38%); also free living amoeba, ciliates and flagellates were detected in all samples. This
... Show MoreHeat transfer around a flat plate fin integrated with piezoelectric actuator used as oscillated fin in laminar flow has been studied experimentally utilizing thermal image camera. This study is performed
for fixed and oscillated single and triple fins. Different substrate-fin models have been tested, using fins of (35mm and 50mm) height, two sets of triple fins of (3mm and 6mm) spacing and three frequencies
applied to piezoelectric actuator (5, 30 and 50HZ). All tests are carried out for (0.5 m/s and 3m/s) in subsonic open type wind tunnel to evaluate temperature distribution, local and average Nusselt number (Nu) along the fin. It is observed, that the heat transfer enhancement with oscillation is significant compared to without o
Gypseous soil, which covers vast area in west, middle, east and south west regions of Iraq exhibit acceptable strength properties when dry, but it is weak and collapsible when it comes in touch with moisture from rain or other sources. When such weak soil is adopted for earth reinforced embankment construction, it may exhibit hazardous situation. Gypseous soil was investigated for the optimum liquid asphalt requirements of both cutback and emulsion using the one-dimensional unconfined compression strength test. The optimum fluid content was 13% (7% of cutback with 6% water content), and 17% (9% of emulsion with 8% water content). A laboratory model box of 50x50x25 cm was used as a representative of embankment; soil or asphalt stabilize
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