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Design and Simulation of GaussianFSK Transmitter in UHF Band Using Direct Modulation of ΣΔ Modulator Fractional-N Synthesizer
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This research involves design and simulation of GaussianFSK transmitter in UHF band using direct modulation of ΣΔ  fractional-N synthesizer with the following specifications:

Frequency range (869.9– 900.4) MHz, data rate 150kbps, channel spacing (500 kHz), Switching time 1 µs, & phase noise @10 kHz = -85dBc.

New circuit techniques have been sought to allow increased integration of radio transmitters and receivers, along with new radio architectures that take advantage of such techniques. Characteristics such as low power operation, small size, and low cost have become the dominant design criteria by which these systems are judged.

A direct modulation by ΣΔ  fractional-N synthesizer is proposed in this research, because this approach provides the required characteristics such as low power. The Σ∆ modulator placed on digital phase-locked loop to control the fractional value of the frequency division ratio thereby eliminating spurious and allowing good phase noise performance. The modulation type of Gaussian FSK is used to obtain high spectral efficiency of modulated waveform.

The applications of this transmitter in low cost wireless data transfer, security systems, RF remote controls and wireless metering.

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Publication Date
Tue Feb 27 2024
Journal Name
Mathematical Modelling Of Engineering Problems
Dynamics of a Fractional-Order Prey-Predator Model with Fear Effect and Harvesting
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Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Structural and morphological study of nanostructured n-type silicon
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In this study, investigations of structural properties of n-type porous silicon prepared by laser assisted-electrochemical etching were demonstrated. The Photo- electrochemical Etching technique, (PEC) was used to produce porous silicon for n-type with orientation of (111). X-ray diffraction studies showed distinct variations between the fresh silicon surface and the synthesized porous silicon surfaces. Atomic force microscopy (AFM) analysis was used to study the morphology of porous silicon layer. AFM results showed that root mean square (RMS) of roughness and the grain size of porous silicon decreased as etching current density increased. The chemical bonding and structure were investigated by using fourier transformation infrared spec

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Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Bayesian Tobit Quantile Regression Model Using Double Adaptive elastic net and Adaptive Ridge Regression
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     Recently Tobit  Quantile Regression(TQR) has emerged as an important tool in statistical analysis . in order to improve the parameter estimation in (TQR) we proposed Bayesian hierarchical model with double adaptive elastic net technique  and Bayesian hierarchical model with adaptive ridge regression technique .

 in double adaptive elastic net technique we assume  different penalization parameters  for penalization different regression coefficients in both parameters λ1and  λ, also in adaptive ridge regression technique we assume different  penalization parameters for penalization different regression coefficients i

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Publication Date
Thu Dec 13 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Study Some Parameters of HCV Isolated From Sample of Hemophilic Patients in Children Welfare Teaching Hospitalin Medical City/Baghdad
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Objective(s) : This study aimed at evaluating the seroprevalence of anti -HCV and studying the
correlation between hemophilia and risk factors for acquiring HCV such as age , marital status &
occupation among hemophilic patients .
Methodology : 210 hemophilic patients in children welfare teaching hospital/medical city/Baghdad–Iraq
(hemophilia center) were investigated using prepared questionnaire and tested for HCV infection, those
were measuring patient’s age, hemophilia types and severity, marital status, residency and history of
previous HCV infection .
Results : Most hemophilic patients were hemophilia A at severe , hemophilia was at age group 20 – 29
years , the majority of patients were unmarried a

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Publication Date
Mon Dec 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Dehydration of Ethanol Using Pervaporation Separation with Nanoporous Hydrophilic Silica Ceramic Membrane
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The pervaporation using a commercial hydrophilic ceramic membrane supplied from PERVATECH was conducted. The dehydration of ethanol/ water system was used as a model for the pervaporation study. Pervaporation experiments of ethanol/water system were carried out in the temperature range of 303-343K, ethanol concentration in the feed 10-90 vol. % and the feed flow rate in the range of 0.5-10 L/min.  In this work, the effect of operation parameters on permeates fluxes as well as permeates separation factors have been studied. The Water flux is strongly dependent on the temperature; it increased with increasing in temperature, which in turn decreased the selectivity of membrane to water molecules.

In addition water flux was decr

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Publication Date
Sun Sep 01 2019
Journal Name
Civil Engineering Journal
Simulation and Assessment of Groundwater for Domestic and Irrigation Uses
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The alluvial fan of Mandali located between latitude 30˚45’00” N longitude 45˚30’00” E in east of Diyala Governorate, Iraq. Thirty-five wells were identified in the study area with average depth of 84 m and estimated area of 21550 ha. A three-dimensional conceptual model was prepared by using GMS program. From wells cross sections, four geological layers have been identified. The hydraulic conductivity of these layers was calculated for steady state condition, where the water levels for nine wells distributed over the study area were observed at same time. Afterward, PEST facility in the GMS was used to estimate the aquifer hydraulic characteristics. Other characteristics such as storage coefficient and specific yield have

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Publication Date
Mon Mar 14 2022
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Mathematical simulation of memristive for classification in machine learning
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Publication Date
Tue Dec 01 2020
Journal Name
Baghdad Science Journal
Novel use of XRF in the adsorption processes for the direct analysis of cadmium and silver in absorbent Na-alginate beads
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         The Na-alginate bead is commonly used in biotechnology fields such as adsorption due to ion exchange between Ca and Na with elements. Scanning electron microscopy (SEM-EDX) has proven to be a comparative method in the detections of these adsorbed elements, but the un-flat forming area of beads that can introduce impossible of the detection of element adsorbed. In contrast, X-ray fluorescence (XRF) documents analysis of elements, direct examination, which may analysis the adsorbents of elements. Here, this Study evaluated the possibility by using XRF for the direct analysis for examples of Cd and Ag in a bench stand. This Study compared this to commonly use

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Publication Date
Mon Dec 01 2014
Journal Name
Journal Of Al-nahrain University Science
Synthesis, Spectroscopic and Antibacterial Studies of N(4-amino phenyl)-N- ((pyridine-4-yl)methyl)Benzene-7,4-Diamine Complexes
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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Experimental Investigations Performance for (VCC) Using 2-Way (PFCV) Type (2FRE)
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In modern hydraulic control systems, the trend in hydraulic power applications is to improve efficiency and performance. “Proportional valve” is generally applied to pressure, flow and directional-control valves which continuously convert a variable input signal into a smooth and proportional hydraulic output signal. It creates a variable resistance (orifice) upstream and downstream of a hydraulic actuator, and is meter in/meter out circuit and hence pressure drop, and power losses are inevitable. If velocity (position) feedback is used, flow pattern control is possible. Without aforementioned flow pattern, control is very “loose” and relies on “visual” feed back by the operator. At this point, we should examine how this valv

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