This research sought to present a concept of cross-sectional data models, A crucial double data to take the impact of the change in time and obtained from the measured phenomenon of repeated observations in different time periods, Where the models of the panel data were defined by different types of fixed , random and mixed, and Comparing them by studying and analyzing the mathematical relationship between the influence of time with a set of basic variables Which are the main axes on which the research is based and is represented by the monthly revenue of the working individual and the profits it generates, which represents the variable response And its relationship to a set of explanatory variables represented by the years of service of the working individual and the academic achievement of him and the classifier starting with (graduates of the intermediate school or below, graduates of the preparatory school, graduates of institutes, graduates of colleges and universities) Finally sex was divided into two categories: male and female The sample of the research is a group of individuals (100) individuals working in private sector companies with different commercial agencies in Baghdad with financial, administrative, technical, sales and services sectors, namely, the research community And then to extract the estimates of the parameters of the models and the Variations of errors as well as their testing and analysis where it was observed how to control the heterogeneity of variance and increase in degrees of freedom and less multicollinearity among the variables, which illustrates the efficiency and importance and accuracy of this type of models and their importance in making sound decisions and reliable results The results also showed the importance of the years of service on the performance of the working individual and the increase in productivity and efficiency, adding to the practical experience of utmost importance, as well as distinguished individuals working in the achievement of university degree on the rest of the other educational collections.
تمثل هذه النقوش طبيعة العصر فيه ؛ لذلك نجد الباحثين المهتمين بعلم اآلثار ، والتاريخ القديم هم أكثر من بحث عنها ، ثم حاولوا فك رموزها ، وما زال بعضها قيد الدراسة .
قال احد المربين ( أعطوني طفولة سعيدة ممتلئة وخذوا شباباً ناضجاً سليماً) ويعني بالطفولة السعيدة تلك الطفولة المشبعة بالحب والحنان وتلبية الحاجات المهمة للطفل حيث يتعلم الطفل من احضان العائلة بعض النواهي والاوامر حتى اذا اتسعت دائرة معارفه شملت الرفقة والعصبة حيث يبدأ الطفل بالتحرر شيئاً فشيئأ من الضوابط العائلية وينتقل مركز ولائه واخلاصه من العائلة الى العصبية وكلما تتوسع علاقات الطفل تزداد خبراته وت
... Show MoreThis research aims at studying the websites of Iraqi ministries to determine the extent of the use of electronic communication in the practice of public relations' activities through these sites, which represent a formal means of communication between the ministry and its people.
The research consists of three chapters: chapter one studies the methodological framework of the research; chapter two includes three units: unit one studies technologies of electronic communication including its concept, features and types; unit two studies electronic publications i.e. its concept and features; and unit three deals with designing the electronic websites .it ends with chapter three which is divided into two sections: section one studies the
Sloped solar chimney system is a solar chimney power plant with a sloped collector. Practically, the sloped collector can function as a chimney, then the chimney height can be reduced and the construction cost would be reduced.The continuity, Naver-stockes, energy and radiation transfer equations have been solved and carried out by Fluent software. The governing equations are solved for incompressible, 3-D, steady, turbulent standard model with Boussiuesq approximation to develop for the sloped solar chimney system in this study and evaluate the performance of solar chimney power plant in Baghdad city of Iraq numerically by Fluent (14) software with orking conditions such as solar radiation intensity (30
... Show MoreThis work presents an experimental study of heat transfer and flow of distilled water and metal oxide nanofluid Fe3O4-distilled water at concentrations of (φ = 0.3, 0.6, 0.9 %) by volume in a horizontal pipe with constant magnetic field. All the tests are carried out with Reynolds number range (2900-9820) and uniform heat flux (11262-19562 W/m2). The results show that, the nanofluid concentration and magnetic intensity increase, the Nusselt number increases. The maximum enhancement in Nusselt number with magnetic nanofluid is (5.4 %, 26.4 %, 42.7 %) for volume concentration (0.3, 0.6, 0.9 %) respectively. The enhancement is maximized with magnetic intensity (0.1, 0.2, 0.3 tesla) respectively to (43.9, 44
... Show MoreA solar updraft tower power plant (solar tower) is a solar thermal power plant that utilizes a combination of solar
air collector and central updraft tube to generate an induced convective flow which drives pressure staged turbines to generate electricity.
This paper presents practical results of a prototype of a solar chimney with thermal mass, where the glass surface is replaced by transparence plastic cover. The study focused on chimney's basements kind effect on collected air temperatures. Three basements were used: concrete, black concrete and black pebbles basements. The study was conducted in Baghdad from August to November 2009.
The results show that the best chimney efficiency attaine
... Show MoreIn this study the adsorption of cefixime on to selected Iraqi clay bentonite. The aim of this study is to search for selective active surface in adsorption of the drug and to act as physical antidotes in treatment of poisoning if the drug is taken in quantities higher than the recommended dosages. Quantitative estimation of the drug adsorption has been done by utilizing the technique of UV spectrophotometry in λmax (273) nm at different conditions of temperature (25, 37, 45) ˚C found the adsorption decrease with increase the temperature. Study of clay weight of bentonite (0.1-1.5) gm found the adsorption increase with increase of clay weight, study effect of pH (1.2, 3, 5, 7) on adsorption of bentonite found the optimum adsorption
... Show MoreThis paper deal with the estimation of the shape parameter (a) of Generalized Exponential (GE) distribution when the scale parameter (l) is known via preliminary test single stage shrinkage estimator (SSSE) when a prior knowledge (a0) a vailable about the shape parameter as initial value due past experiences as well as suitable region (R) for testing this prior knowledge.
The Expression for the Bias, Mean squared error [MSE] and Relative Efficiency [R.Eff(×)] for the proposed estimator are derived. Numerical results about beha
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