Orthogonal Frequency Division Multiplexing (OFDM) is one of recent years multicarrier modulation used in order to combat the Inter Symbol Interference (ISI) introduced by frequency selective mobile radio channel. The circular extension of the data symbol, commonly referred to as cyclic prefix is one of the key elements in an OFDM transmission scheme. This paper study The influence of the cyclic prefix duration on the BER performance of an OFDM-VCPL (Orthogonal frequency division multiplexing - Variable Cyclic Prefix Length) system and the conventional OFDM system with frame 64-QAM modulation is evaluated by means of computer simulation in a multipath fading channel. The adaptation of CP is done with respect to the delay spread estimation of the channel.
In The Bluest Eye (1970) , Toni Morrison addresses a timeless problem of white racial dominance in the United States and points to the impact it has on the life of black females growing up in the 1930's. Morrison in this novel explores how Western standards of ideal beauty are created and propagated with and among the black community. The novel not only portrays the lives of those whose dark skinned and negroid features blight their lives; it also shows how the standards of white beauty are imposed on black youth to cause a damage of one's self-love and esteem which usually occurs when beauty goes unrecognized
The study analyzed the current situation of public hospitals in the capital of Baghdad exclusively and diagnosed the resources available; especially after the high demand for these hospitals as a result of the citizen’s need to review the hospital to take care of them, especially after the Corona pandemic. Eight major hospitals in Baghdad were selected to determine the current reality of providing fire safety tools or equipment and what are the preventive measures needed to reduce it. The results after practical study showed many defects and weaknesses in the current situation due to their reliance on the traditional management to manage and provide all preventive measures and safet
Internal conversion coefficients (ICC) and electron–positron pair conversion coefficients (PCC) for multipole transition of the core nucleus 88Sr have been calculated theoretically. The calculation is based on the relativistic Dirac–Fock (DF) solutions using the so called ‘‘Frozen Orbital’’ approximation, takes into account the effect of atomic vacancies created in the conversion process, covering a transition energies of 1–5000 keV. A large number of points were used to minimize any errors due to mesh-size effects. The internal conversion coefficients display a smooth monotonic dependence on transition energy, multipolarity and atomic shell. Comparing the values of PCC to ICC, it is interesting to note, that the energy dep
... Show MoreEarth cover of the city of Baghdad was studied exclusively within its administrative border during the period 1986-2019 using satellite scenes every five years, as Landsat TM5 and OLI8 satellite images were used. The land has been classified into ten subclasses according to the characteristics of the land cover and was classified using the Maximum Likelihood classifier. A study of the changing urban reality of the city of Baghdad during that period and the change of vegetation due to environmental factors, human influences and some human phenomena that affected the accuracy of the classification for some areas east of the city of Baghdad is presented. The year 2019 has been highlighted because of its privacy in changing the land cover of th
... Show MoreThis study can be considered as un introduction to the idioms and the strategy about the productive partnership development connection, that helps the researcher and the organization in their work in to activate development and the natural sources,manegment,to improve the two sides active connected to the local society, and to use it as easier and smoother participation of the people who work in development field and the natural sources management research, That connection depends mostly upon the capability of researcher and the development worker to increase the ability of individual and local society to specify and analyzing their problems and to try solutions to make their life better with good income.
Electrical distribution system loads are permanently not fixed and alter in value and nature with time. Therefore, accurate consumer load data and models are required for performing system planning, system operation, and analysis studies. Moreover, realistic consumer load data are vital for load management, services, and billing purposes. In this work, a realistic aggregate electric load model is developed and proposed for a sample operative substation in Baghdad distribution network. The model involves aggregation of hundreds of thousands of individual components devices such as motors, appliances, and lighting fixtures. Sana’a substation in Al-kadhimiya area supplies mainly residential grade loads. Measurement-based
... Show MoreThe current study included a review of the registration and description of the Theretra alecto Boi, 1827 (Levant hawk moth), samples were collected from various areas of the Baghdad belt and the provinces of the Middle Euphrates, confirmation in the description was on the most important parts of the body included the head and it's appendages, pronotum, wings as well as male and female genitalia. The morphological characteristics under study were enhanced by illustrations and images. Information on the locations and date of the collection was also confirmed. This study aims to identify the most important characteristics of the diagnosis of the species and the review of appearance variations, especially the analytical style of wings, coupling
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