The current study was conducted in the environment of the Martyr Monument Lake in the city center of Baghdad during 2019 to monitor the impact of climatic conditions such as drought, water shortage, high temperatures in the environment of the city and the lack of water flow during the years 2015 to 2018 and their effects on some of the physical and chemical factors of water and the dynamics of the phytoplankton community in the lake environment. Heterogeneity of some studied environmental factors, including air and water temperature, permeability, water depth, pH, DO, BOD5, nutrients, nitrate, NO3, and phosphates were found. The results showed the effect of climate change and the presence of organic pollution in addition to the influence of the nature of sites. Sampling on the studied characteristics, which in turn affected the phytoplankton community. The results showed the fluctuations in the rates of air and water temperature, which were between 17 - 41 ° C and 10 - 32 ° C, respectively, as well as the fluctuation of light transmittance rates and water depth according to the different stations and seasons, as they ranged between 0.12-57.02 cm and 120.5- 289.30cm. The pond water was characterized by being neutral and tilted to alkaline in terms of pH 7.0-9.1. The values of dissolved oxygen and vital oxygen requirement rise in winter and gradually decreased in spring and autumn, and the lowest values in summer were 2.4-15.13 mg / liter 0.4-10.6 mg / liter, respectively. The changes in nitrate values rise in winter and decreased in summer in all locations, where they ranged between 2.2 - 12.4 mg, in contrast to phosphate, it increased in the summer winter 0.0033 - 0.5 mg / liter. The qualitative study of phytoplankton identified 125 species belonging to 46 genera. It belongs to 5 classes in which the class of green algae prevailed with 69 species, followed by blue-green algae (39 species), while Euglenophyta and Pyrrophyta recorded 7 species each, while the Cryptophyta algae recorded only 3 types. The study showed that the decrease in the water level and the fluctuation of temperature led to an increase in blue-green algae in areas of organic pollution in which some species such as Microcystis aeruginosa and Oscillatoria spp. Causing the appearance of unpleasant odors and the secretion of deadly toxins to the aqueous medium.
The study conducted on the compositions of epiphytic diatoms on three taxa of aquatic plants were selected (Phragmites australis Trin ex stand , Ceratophyllum demersum L. and Typha domengensis Pers) in three sites within Al-Auda Marsh, from autumn 2013 to summer 2014 . The study was measured physical and chemical factors of all the study sites, such as: air temperature, power of hydrogen (pH), electrical conductivity (EC), salinity (S‰), total hardness(TH), dissolved oxygen (DO), and plant nutrient. The results showed that water of marsh was oxygenated and it was very hard. A total of 111 taxa of phytoplankton were identified, which belonged to 13 families and 26 genus (one family and two genus of centric diatoms, 12 families and 26 ge
... Show MoreThe theory of Pilgrims in the Magra is based on Dekru's view that the mgha is considered a pilgrim, and that the pilgrims are pilgrims
Tujia purely exposes the abstract temptation structure, and that the discharge of the Mfezouz Mfarouz is through factors
This theory tends to highlight the role of pilgrim function as a language
There is no preservation unless directed towards a particular outcome. Gemma can include morphine blindness
Or formulas that allow for the presentation of a pilgrimage to a writer in addition to the content of the news, and the guidance of the recipient
In one direction or another.
The orbital masses are one of these morphines and functional components that achieve function
The Togolese
In this article, we developed a new loss function, as the simplification of linear exponential loss function (LINEX) by weighting LINEX function. We derive a scale parameter, reliability and the hazard functions in accordance with upper record values of the Lomax distribution (LD). To study a small sample behavior performance of the proposed loss function using a Monte Carlo simulation, we make a comparison among maximum likelihood estimator, Bayesian estimator by means of LINEX loss function and Bayesian estimator using square error loss (SE) function. The consequences have shown that a modified method is the finest for valuing a scale parameter, reliability and hazard functions.
In this paper, variable gain nonlinear PD and PI fuzzy logic controllers are designed and the effect of the variable gain characteristic of these controllers is analyzed to show its contribution in enhancing the performance of the closed loop system over a conventional linear PID controller. Simulation results and time domain performance characteristics show how these fuzzy controllers outperform the conventional PID controller when used to control a nonlinear plant and a plant that has time delay.
In this paper, variable gain nonlinear PD and PI fuzzy logic controllers are designed and the effect of the variable gain characteristic of these controllers is analyzed to show its contribution in enhancing the performance of the closed loop system over a conventional linear PID controller. Simulation results and time domain performance characteristics show how these fuzzy controllers outperform the conventional PID controller when used to control a nonlinear plant and a plant that has time delay.
In this paper, we present a comparison of double informative priors which are assumed for the parameter of inverted exponential distribution.To estimate the parameter of inverted exponential distribution by using Bayes estimation ,will be used two different kind of information in the Bayes estimation; two different priors have been selected for the parameter of inverted exponential distribution. Also assumed Chi-squared - Gamma distribution, Chi-squared - Erlang distribution, and- Gamma- Erlang distribution as double priors. The results are the derivations of these estimators under the squared error loss function with three different double priors.
Additionally Maximum likelihood estimation method
... Show MoreThe steady state performance of the counter rotating floating ring Journal bearing is analyzed with isothermal finite bearing theory. The effect of different parameters affecting the performance of the bearing (namely speed ratio, clearance ratio and radii ratio), have been investigated. The load carrying capacity of the bearing increasing with decreasing the radii ratio (R2/R1) of the ring and clearance ratio (c1/c2), in the other hand, the coefficient of friction increases with increasing the clearance and radii ratios, while decreases with incre4asing the bearing to journal speed ratio (γ). It is shown during this work that different operating conditions are greatly enhanced the performance
... Show MoreExperimental investigation for small horizontal portable wind turbine (SHPWT) of NACA-44, BP-44, and NACA-63, BP-63 profiles under laboratory conditions at different wind velocity range of (3.7-5.8 m/s) achieved in present work. Experimental data tabulated for 2, 3, 4, and 6- bladed rotor of both profiles within range of blade pitch angles . A mathematical model formulated and computer Code for MATLAB software developed. The least-squares regression is used to fit experimental data. As the majority of previous works have been presented for large scale wind turbines, the aims were to present the performance of (SHPWT) and also to make a comparisons between both profiles to conclude which is the best performance. The overall efficiency and el
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