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.
In this paper a comparison of the experimental of evacuated tube solar water heater systems with and without mirror flat reflector. The aim of using the reflector to improve thermal efficiency, and the data gathered which are (temperature, solar irradiation and time) for three days were compared. the results from compared data the temperature lower increase in evacuated tube solar water heater system without reflector than the temperature increase in evacuated tube solar water heater system with reflector .The results show (53, 39, 35) % for three days respectively that the evacuated tube solar water heater system with reflector has higher thermal efficiencies than the results (47, 28, 30) % for three days respectively thermal efficiencies
... Show MoreNearly a century and a half has passed since Sarah Orne Jewett published her much anthologized short story “A White Heron” (1886), but commentators on the tale missed one of the most important points in the text. It is the story’s similarity to the traditional Euro-centric fairy tale of “Little Red Riding Hood”. As an author, writing at the end of the ninetieth century, a time that witnessed the demise of the Romantic movement in America and the beginning of the age of Realism, Jewett did not romanticize her characters, despite the idyllic landscape in which “A White Heron” is set. Her story can be analyzed as a text that aims at disseminating ecological awareness among her young readers. This study focuses on Jewett
... Show MoreBackground: Determination of sex from an unknown human bone is an important role in forensic and anthropology field. The mandible is the largest and hardest facial bone, that commonly resist postmortem damage and forms an important source of information about sexual dimorphism. Mandibular ramus can be used to differentiate between sexes and it also expresses strong univariate sexual dimorphism. This study was undertaken to assess the usefulness of mandibular ramus as an aid in sex differentiation using CT scanning among Iraqi population. Materials and methods: 3D reconstructed computed tomography scanning of 140 Iraqi Arab subjects, (7 0 males and 70 females) were analyzed with their age range from 20-60 years old. The linear measurements w
... Show MoreOne of the most important problems in the oil production process and when its continuous flow, is emulsified oil (w/o emulsion), which in turn causes many problems, from the production line to the extended pipelines that are then transported to the oil refining process. It was observed that the nanomaterial (SiO2) supported the separation process by adding it to the emulsion sample and showed a high separation rate with the demulsifiers (RB6000) and (sebamax) where the percentage of separation was greater than (90 and 80 )% respectively, and less than that when dealing with (Sodium dodecyl sulfate and Diethylene glycol), the percentage of separation was (60% and 50%) respectively.
The high proportion
... Show MoreThe heat transfer and flow resistance characteristics for air flow cross over circular finned tube heat exchanger has been studied numerically and experimentally. The purpose of the study was to improve the heat transfer characteristics of an annular finned-tube heat exchanger for better performance. The study has concentrated on the effect of the number of perforations and perforations shapes on the heat transfer and pressure drop across a staggered finned tube heat exchanger. The Numerical part of present study has been performed using ANSYS Fluent 14.5 using SST Turbulent model, while the experimental study consist from a test rig with different models of heat exchangers and all required measurement devices were build
... Show MoreRandom matrix theory is used to study the chaotic properties in nuclear energy spectrum of the 24Mg nucleus. The excitation energies (which are the main object of this study) are obtained via performing shell model calculations using the OXBASH computer code together with an effective interaction of Wildenthal (W) in the isospin formalism. The 24Mg nucleus is assumed to have an inert 16O core with 8 nucleons (4protons and 4neutrons) move in the 1d5/2, 2s1/2 and 1d3/2 orbitals. The spectral fluctuations are studied by two statistical measures: the nearest neighb
Sickle cell disease (SCD) is a hereditary ailment that can cause severe pain and suffering to people who are affected. However, with continued investment in research and treatment options, we can make progress towards improving the lives of those with SCD. Over 40% of patients experience painful vaso-occlusive crises (VOCs), so we must work towards finding solutions and providing support for those living with this condition, These episodes, a hallmark of SCD, significantly contribute to morbidity, mortality, and a diminished quality of life, while also incurring substantial healthcare costs. Chronic pain particularly affects older adolescents and adults with SCD, with over half reporting daily discomfort. Opioid-based analgesics, though sti
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