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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
Fri Aug 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Efficiency Measurement Model for Postgraduate Programs and Undergraduate Programs by Using Data Envelopment Analysis
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Measuring the efficiency of postgraduate and undergraduate programs is one of the essential elements in educational process. In this study, colleges of Baghdad University and data for the academic year (2011-2012) have been chosen to measure the relative efficiencies of postgraduate and undergraduate programs in terms of their inputs and outputs. A relevant method to conduct the analysis of this data is Data Envelopment Analysis (DEA). The effect of academic staff to the number of enrolled and alumni students to the postgraduate and undergraduate programs are the main focus of the study.

 

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Publication Date
Mon Jun 01 2015
Journal Name
Journal Of Engineering
Variation of Compression Index and Swelling Index with Degree of Saturation in Unsaturated Soils
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The variation of compression index Cc and swelling index Cs with the degree of saturation S was studied on unsaturated and fully saturated soils for different degrees of saturation (100%, 91%, 85%, 75%, 60%), several mathematical equations were found to describe these relationships, these equations can be used to predict settlement during the consolidation process in unsaturated and fully saturated soils.

 

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Publication Date
Mon Nov 01 2010
Journal Name
Iraqi Journal Of Physics
Plasma Dynamics and Pulse Shape Rules in Laser Heating of Opaque Targets in Ai
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A theoretical model is developed to determine time evolution of temperature at the surface of an opaque target placed in air for cases characterized by the formation of laser supported absorption waves (LSAW) plasmas. The model takes into account both plasma dynamics and time variation of incident laser pulse (i.e. pulse shape or profile).Shock tube relations were employed in formulating plasma dynamics over target surface. Gaussian function was chosen in formulating the pulse profile in the present modeling

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Publication Date
Tue Sep 15 2020
Journal Name
Al-academy
The actor's Body Language and its significance in Iraqi Theatre Show: نوار علي محمد
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  The theatrical show has gone through a lot of changes where the actor was the most significant factor in all the theatrical shows since the very beginning of the art of acting by the Greeks until the present day. The actor went through many stages that employed his tools in different ways. The body in the theatre had a great importance because it is the perceived physical element that creates the communication between the actor and the audience in the theatrical show. The actor's body had a special language that carries different meanings and creates the communication between the actor and the audience in the theatrical show. The audience can decipher the codes of that body, thus, the researcher found the compatibility and differe

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Publication Date
Wed Oct 28 2020
Journal Name
Iraqi Journal Of Science
Relationship Between Osteopontin Biochemical Parameters and BMD Status in Iraqi Postmenopausal Women with Osteoporosis
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Osteopontin hormone (OPN) is an extracellular matrix protein that is expressed in bone cells such as osteoblasts and osteoclasts and associated with bone turnover and bone mineral density (BMD) in postmenopausal women with osteoporosis.

     The aim of the study is to investigate serum levels of circulating OPN and its relationship with biochemical parameters and BMD in postmenopausal women with osteoporosis in Iraq. Serum samples from fifty postmenopausal women were selected from patients attending two educational hospitals in Baghdad, which are AL Wasity Educational Hospital and Baghdad Educational Hospital, during the period from November 2018 to March 2019. Twenty five postmenopausal healthy women were inc

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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
International Auditing Standards and their role in rationalizing the auditor's personal judgment in Iraq"
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The impact of the auditor's personal judgment starts from the beginning of the audit process to the formation of the final opinion and the issuance of the report, and because of the possibility of bias in the auditor's judgment for various reasons that may relate to the auditor himself or the circumstances surrounding it, which requires assessing the current reality of the auditor's personal judgments In the local environment and determining their determinations. To clarify the concept and determinants of the auditor's personal judgments when implementing the audit work, prepare the report and determine the role of the international auditing standards in rationalizing the auditor's personal judgment when conducti

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Publication Date
Wed Aug 28 2019
Journal Name
Journal Of Engineering
Influence of Liquid Asphalt on Resilient Modules and Permanent Deformation of Recycled Asphalt Concrete
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Tests were performed on Marshall samples and were implemented for permanent deformation and resilient modulus (Mr) under indirect tensile repeated loading (ITRL), with constant stress level. Two types of liquid asphalt (cutback and emulsion) were tried as recycling agents, aged materials that were reclaimed from field (100% RAP), samples were prepared from the aged mixture, and two types of liquid asphalt (cutback and emulsion) with a weight content of 0.5% were utilized to prepare a recycled mixture. A group of twelve samples was prepared for each mixture; six samples were tested directly for ITRL test (three samples at 25˚C and three samples at 40˚C), an average value for ITRL for every three samples was calculated (

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Publication Date
Tue Aug 31 2021
Journal Name
Iraqi Journal Of Science
Biochemical and Genetic Study in Blood of β– Thalassaemia Children in Mosul City, Iraq
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The present study aimed to demonstrate the extent to which the activity of a number of enzymes and genetic variation of β-globin genes were affected in the blood of 65 children with β - thalassemia major of both sexes. The patients, with an age range of 2 – 15 years, were registered in the Thalassemia Center at Ibn Al-Atheer Teaching Hospital for Children in the city of Mosul / Iraq. They were under continuous treatment after being diagnosed by specialist doctors. The study also involved 30 healthy children of both sexes with the same age range who were considered as a control group.

       The results showed significant increases (p≤0.05) in the activities of alanine transaminase (ALT), aspart

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Publication Date
Fri Jan 08 2010
Journal Name
Al-kindy College Medical Journal
Maternal and fetal outcomes in emergency versus elective two or more previous cesarean deliveries
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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Pharmaceutical Sciences And Research
Synthesis and biological activity of new esters derived from D-fructose-containing isoxazole moiety
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Background: Isoxazoles are an important class of five-membered unsaturated heterocyclic compounds. They show several applications in diverse areas such as pharmaceuticals, agrochemistry and industry. Isoxazoles are also found in natural sources showing insecticidal, plant growth regulation and pigment functions. Current study was conducted for synthesis of twenty five new Isoxazole derivatives and to evaluate the in vitro antibacterial activities of these derivatives. Methods: Benzaldoxime and their substituted [I] ae were prepared via addition-elimination reactions between aromatic aldehyde and hydroxylamine hydrochloride. In a second step, para-or meta-substituted benzaldoximes [I] ae were reacted with N-chlorosucceinimide in DMF to yield

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