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Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used.

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Publication Date
Wed Jan 30 2013
Journal Name
Al-kindy College Medical Journal
MODIFICATION OF TUBULARIZED INCISED PLATE URETHROPLASTY IN HYPOSPADIUS REPAIR FOR PREVENTING FISTULA AND MEATAL STENOSIS.
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Objective: to evaluate the benefit of coverage of
the urethral repair by dorsal dartos flap as a second
layer for preventing fistula and V like incision on
the tip of the glans for preventing meatal stenosis.
Patients and Methods:
Forty five children included in this study age
ranged ( 11 months – 7 years), they underwent
hypospadias repair between December 2008 to
March 2012, all cases with distal hypospadias,
same technique used for all patients, a combination
of techniques used for reconstruction starting
withtubularized incised plate urethroplasty with deepithelialized
or stripping of the skin from both
sides of U shaped incision surrounding the urethral
plate, adding a V like incision on t

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Publication Date
Mon Mar 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Anti-oxidant Activity of Methanol Extracts of Arum maculatum L. and Physalis peruviana L. Plants
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       Total flavonoid contents, reductive ability and radical scavenging activity were studied in the methanol extracts of Arum maculatum L. and Physalis peruviana L. The results revealed that A. maculatum extract had total flavonoids of 535.3±109.9 µg/ml, which was significantly higher than the recorded flavonoids in P. peruviana extract (352.0±12.7 µg/ml). Assessment of reductive ability revealed that both extract were effective in such activity and concentration-dependent. The highest absorbance was found at the concentration 0.64 mg/ml of A. maculatum methanol extract (0.929±0.006), which was significantly higher (P ≤ 0.05) than the corresponding concentration of P. peruviana extract (0.850

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Publication Date
Thu Mar 31 2022
Journal Name
Journal Of The College Of Education For Women
Social Risks and Development Gaps in Iraq: A Social Study in the City of Baghdad
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Social risks posed a great challenge to the development path in Iraq, which resulted in widening the development gaps, whether these gaps were between rural and embargoed areas, or between Iraqi governorates, and the gender gap. Besides, the nature of the reciprocal relationship between the social risks and the development process requires the adoption of development trends that are sensitive to the risks that take upon themselves the prompt and correct response to these risks, away from randomness and confusion that Iraq suffered from for decades. However, currently, the situation has differed a great deal. This is because the size and types of such gaps have widened and become more complicated than before; a matter which has led to hav

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Requirements of talent management in high- containment organizations/ field study in Technology and Science Ministry
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Human resources constitute the most important recourses that the organization owned today, as it may have developed financial and technology resources to achieve their goals, but they are not able to use it with required efficiency and effective and quality desired unless there is human resources that have good skills, experiences and talents that able to directing and exploited ideally that compatible  with market requirements, where today's market and business organizations which compete naturally inherent talent, so the task is to attracting and developing talented resources and preservation these talented resources from the challenges that facing organizations. 

The research seek to achieve

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Publication Date
Thu May 14 2020
Journal Name
Journal Of Planner And Development
Visual Pollution and its Impact on the Aesthetics: The Town of Eizariya as a Model
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This study seeks to shed light on the aspects of visual pollution and its impact on the aesthetics of the town of Al-Eizariya known to suffer from the phenomenon. In order to identify the real causes of the problem which develops in various forms and patterns, threatening not only the aesthetic appearance of the towns, but also causes the emergence of new problems and phenomena that will have negative repercussions on the population. The researcher uses the analytical descriptive method to analyze the phenomenon of visual pollution in terms of reality, development, manifestations and spread and uses photos which document the visual pollution and its impact on the aesthetics of the known. The study concluded the existence of a strong rela

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Publication Date
Wed Oct 31 2018
Journal Name
Iraqi Journal Of Science
Structural and morphological investigation of bulk heterojunction blend (NiPc/C60) Thin films under heat treatment
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Thin films of the blended solution of NiPc/C60 are fabricated using spin-coating method for three different ratios (100/1, 100/10 and 100/100) according to the weight. The films are deposited on to glass substrates and treated with several annealing temperatures (373, 423 and 473)K. The structure and surface morphology of the as-deposited and annealed films using x-ray diffraction and AFM was studied and exhibited a change and enhanced crystallization and surface morphology caused by changes in heat treatment temperatures. Investigation of X-ray diffraction patterns of NiPc/C60 indicated that it have polymorphism structure, i.e. mix between amorphous and polycrystalline structure. when heat treatment temperatures ch

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Publication Date
Sun Mar 04 2018
Journal Name
Iraqi Journal Of Science
Determination the Quantity of Extreme Rainfall and calculation of the Climatology Mean for Baghdad City
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Recently heavy rainfall that occurs in last decade for Baghdad city is part of climate changes effect on Iraq in general and Baghdad in particular. Rain is considered the main part in the water cycle as it enters mainly within the water system and water balance; therefore present study put of a special criterion to determine the amount of rainfall and analyzed in order to quantify the amount and the diagnosis of heavy rain. The availability of data by Iraqi Metrological  Organization  and Seismology (IMOS) for time period (1985/1986-2014/2015) held achieve the research objective .There are many statistical methods figure out  the difference to determine the amount of rain, Climatology mean  (C M) is one of them specia

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Publication Date
Mon May 02 2022
Journal Name
International Journal Of Research In Social Sciences & Humanities An International Open-access Peer Reviewed Referred Journal
Identity Construction and Social Structures in Sia Figiel&#8217;s Novel Where We Once Belonged
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This article focuses on identity construction and social structures within the Sāmoan community as represented in Sia Figiel’s novel Where We Once Belonged. I argue that however the post/colonial Sāmoan identity is hybridized, the essence of the individual is still connected to Fa’a Sāmoa-the Sāmoan traditions and ways. However rapid are the colonial vicissitudes, the Sāmoan literature and lifestyle are developed to be a resistance platform. This resistance platform is dedicated not only to expose the colonial impact but also to assist the social and political reconstruction of post/colonial Samoa. To this end, this article studies identity construction, and the challenges that women face within Sāmoan social structures.

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Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Languages (jcl)
A Contrastive Study on the Syntactic Structure of Standard English and Standard Arabic Determiner Phrase
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The determiner phrase is a syntactic category that appears inside the noun phrase and makes it definite or indefinite or quantifies it. The present study has found wide parametric differences between the English and Arabic determiner phrases in terms of the inflectional features, the syntactic distribution of determiners and the word order of the determiner phrase itself. In English, the determiner phrase generally precedes the head noun or its premodifying adjectival phrase, with very few exceptions where some determiners may appear after the head noun. In Arabic, parts of the determiner phrase precede the head noun and parts of it must appear after the head noun or after its postmodifying adjectival phrase creating a discontinu

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Publication Date
Sun Feb 02 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The relation between facial prognathism and cervical posture in skeletal class I Iraqi adult sample
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Background: Biologic mechanisms of the form-function interaction are one of important component of orthodontic diagnosis. The purpose of this study is to search for the statistical associations between natural postural and craniofacial morphologic variables of the head. Materials and methods: The sample comprised natural head posture (NHP) cephalograms of 90 subjects, aged 18 to 25 years. Interpretation of the facial structure was made by using both intracranial and the extra-cranial reference lines in AutoCAD computer program. Results The measures of anteroposterior maxillary position, SNA showed a low negative correlations with the anterior cranial base angulation to true vertical (SN.Ver) and with the cranio-cervical position of the head

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