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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 Apr 12 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
IGF-1 , Leptin & AIP in relation to Osteoarthritis with and without Diabetes Mellitus Type2
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        IGF-1  is a protein  produced  by  the liver in  response  to  growth hormone   stimulus.One important  key in effectively  preventing  and   treating  osteo arthritis, is establishing a healthy balance of IGF-1.    Leptin is a hormone  produced   by  adipose tissue,   acting as a  sensor  of  fat  mass in  part  of   a negative   feedback   loop   that maintains  a  set  point  for  body  fat  stores.  Leptin  plays  an important  role  in &nbs

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Publication Date
Sun Dec 06 2009
Journal Name
Baghdad Science Journal
Preparation of Electrical Conducting Polymer CompositesFrom Polyvinylchloride (PVC) Resin and StudyingSome its Electrical Properties
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The D.C electrical and thermoelectrically properties of randomly mixed isolator – electrolyte system as (Al/ PVC – LiF/Al) junction consisting of polyvinyl chloride (PVC)resin reinforced with Lithium Fluoride (LiF) powder were studied. A comparison is made the properties of (PVC) material with varying percentage of (LiF) powder (0%, 30%, 50%, 80%)to find out the effect of reinforcement of isolator material. The composites dissolving in 10ml form tettraHaedroflourn (THF) and Solution were the castled in Petri dish and Laved it dry in the air, The out coming Sample were disc - Like shape of a diameter of about 3cm and thickness reneged between (0.01- 0.018) cm . The composites dissolving in 10ml form tettraHaedroflourn (THF) a

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Publication Date
Thu Jun 15 2023
Journal Name
Journal Of Legal Sciences
Compulsory Licensing for Patent Exploitation between Exclusion and Restriction Accordance to the Emirati Law
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The patent means that the inventor is granted a right of intellectual property that is solely acquired by the patent's owner. This study highlights the compulsory licensing provisions that entitle government agencies to exploit the inventor's patent and to exploit it in the manufacture of goods and industries by a third party without the consent of the patent owner for reasons required by the interest of society.

This means has been referred to by Decree-Law No. 11 of 2021 on the regulation and protection of industrial property rights. However, the UAE legislator has made recourse to this means an exception, restricting this means by justification required by the public interest of society.

The study will focus on the des

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Publication Date
Sun Apr 04 2010
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Possible Association of HLA-DR and DQ Molecules with Autoimmune Hepatitis in Iraqi Patients
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Background: Human leukocyte antigen (HLA) is the most polymorphic genetic system in man. The genes of this region seem to influence susceptibility to certain diseases.
Patients and methods: Polymerase chain reaction-Sequence Specific Primers PCR-SSP is the method used to asses HLA-typing of 100 blood samples of 60 AIH patients and 40 healthy normal controls.
Results: An increased frequency of HLA-DR3, DR4 and DR7 was observed for patients group versus control group with P-value (0.0001, 0.05, and 0.001) respectively, while DR*0211 (DR2) may be formed the basis for protection against the disease. HLA-DQ on the other hand, yielded on association in Iraqi patients with AIH.
Conclusions: This finding de

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Publication Date
Sun Dec 16 2018
Journal Name
Al-academy
The Overlap of Visions between the Scenographer and the Director in the Theatrical Show
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After the spread of the function of the scenographer in the modern theater, his vision has become present in most of the theatrical works and because the director is the master of the work and the owner of the vision that appears in front of the audience, the overlap between the visions of each of them was required. This research is an attempt to detect the overlap and disengagement in the work of each of them.
The research is divided into a methodological framework that included the research problem, importance, limits, and purpose, and then the definition of terms. In the theoretical framework, the research dealt with two theoretical sections that pave the way for raising ideas related to this subject: the first section (scenography

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Effect of thickness on the structure, morphology and A.C conductivity of Bi2S3 thin films
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Thin films samples of Bismuth sulfide Bi2S3 had deposited on
glass substrate using thermal evaporation method by chemical
method under vacuum of 10-5 Toor. XRD and AFM were used to
check the structure and morphology of the Bi2S3 thin films. The
results showed that the films with law thickness <700 nm were free
from any diffraction peaks refer to amorphous structure while films
with thickness≥700 nm was polycrystalline. The roughness decreases
while average grain size increases with the increase of thickness. The
A.C conductivity as function of frequency had studied in the
frequency range (50 to 5x106 Hz). The dielectric constant,
polarizability showed significant dependence upon the variation of
thic

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Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Determination of uranium concentrations for soil of Tigris river and rainwater of Baghdad city
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In this study, phosphorescence analysis (KPA) is used for determining soil collected from the Tigris River from Al- Karrada and Bab Al-Sharq in Baghdad and samples were taken from rainwater collected from Al-Rashad, Al-Obeidi, Al-Dora and Al-Sadr City in Baghdad. The measurements were carried out by the Iraqi Ministry of Health and Environment, in the Radiation Protection Center. The collection, removal and evaporation of the samples ranged from January to the end of March 2018. The results show the presents of concentration of 238U and 235U in soil samples and the rainwater samples. The conclusion of this work is the concentration of uranium in soil samples is more than recommendations by ICRP value of 1.9 μg /l. While all water sample

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Publication Date
Fri May 01 2015
Journal Name
Journal Of Engineering
Cooling Load Calculations For Typical Iraqi Roof And Wall Constructions Using Ashrae's RTS Method
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The present work is an attempt to develop design data for an Iraqi roof and wall constructions using the latest ASHRAE Radiant Time Series (RTS) cooling load calculation method. The work involves calculation of cooling load theoretically by introducing the design data for Iraq, and verifies the results experimentally by field measurements. Technical specifications of Iraqi construction materials are used to derive the conduction time factors that needed in RTS method calculations. Special software published by Oklahoma state university is used to extract the conduction factors according to the technical specifications of Iraqi construction materials.  Good agreement between the average theoretical and measured cooli

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Publication Date
Mon Oct 02 2023
Journal Name
Journal Of Engineering
Comparative Study between Recycled Fine and Coarse Aggregate Used in Roller Compacted Concrete Pavement
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To decrease the impact on the environment of building waste, the recycled aggregate may be used in various sustainable engineering applications, such as roller compacted concrete pavement (RCCP). This research examined how using recycled aggregate as a partial replacement for natural aggregate as coarse or fine affected the mechanical properties of roller-compacted concrete pavement. The recycled aggregate was crushed and sieved to coarse and fine aggregate before being used in the roller-compacted concrete pavement. Compressive strength, splitting tensile strength, and flexural strength were all evaluated after the samples were prepared at 28 and 90 days of curing. According to the study's findings, the partial replacem

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Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
biofuels industry and impact on the development of the agricultural sector in developing countries
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Abstract

       Although the subject of biofuels industry is linked directly to the energy sector, but has links and numerous indirect effects, in particular effects on the environment and agriculture, this study (opportunities and challenges of biofuels industry and impact on the development of the agricultural sector in developing countries) a modest step to identify the industry in detail and identify the types of products and raw materials entering, then define or limit the positive and negative impacts of this industry in General and for specific products In particular, detailed, and then flip all those effects on the agricultural sector in developing countries can benef

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