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alkej-29
Design & Implementation of High Switching & Low Phase Noise Frequency Synthesizer
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This research  describes the design & implementation of frequency synthesizer using single loop Phase lock loop with the following specifications: Frequency range (1.5 – 2.75) GHz,Step size (1 MHz), Switching time 36.4 µs, & phase noise @10 kHz = -92dBc & spurious -100 dBc

  The development in I.C. technology provide the simplicity in the design of frequency synthesizer because it implements the phase frequency detector(PFD) , prescalar &  reference divider in single chip. Therefore our system consists of  a single chip contains (low phase noise PFD, charge pump, prescalar  & reference divider), voltage controlled oscillator , loop filter & reference oscillator. The single chip is used to provide the following properties :

  • Low power consumption.
  • Small size, light weight.
  • Flexibility in selecting crystal oscillator frequencies to fit into the system frequency planning.
  • High reliability.

The application of this synthesizer  in frequency hopping systems, satellite communications & radar because it has high switching speed  ,low phase noise & low spurious level.

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Publication Date
Wed Jan 02 2019
Journal Name
Journal Of Educational And Psychological Researches
An Instructional Design According to the Active Learning Model and Its Effect on Students' Achievement in Chemistry for Fifth Intermediate Stage
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The objective of the research is to identify the effect of an instructional design according to the active learning modelsالباحثين in the achievement of the students of the fifth grade, the instructional design was constructed according to the active learning models for the design of education. The research experience was applied for a full academic year (the first & the second term of 2017-2018). The sample consisted of 58 students, 28 students for the experimental group and 30 students for the control group. The experimental design was adopted with partial and post-test, the final achievement test consisted of (50) objectives and essays items on two terms, the validity of the test was verified by the adoption of the Kudoric

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Publication Date
Fri Jun 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Relationship between federal budget estimates And actual implementation
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he public federal budget of the state includes estimated figures for state revenues and expenditures for the next fiscal year. The estimation process is one of the main parts of the preparation of the general budget of the state and the accuracy in the estimation of revenues and expenditures of the most important principles that should be based on the process of making estimates and should not overestimate the assessment process to ensure the availability of funds in the future in all cases, which lead to unfair distribution of allocations, so the research aims to study The case of preparing the budget in the Directorate and how to estimate the expenditure in, by the analysis of operating budgets and identify deviations in the implementa

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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Synthesis and Characterization of Nanocrystalline Zeolite Y
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Worldwide attention is being focused on  nanocrystalline  zeolites  and they are replacing conventional ones due to their pronounced potential in many fields. In this study, NaY zeolite has been prepared hydrothermally using sol –gel method and modified to the proton type by ion –exchange process. Characterization is made using X-ray diffraction (XRD), thermogravimetric analysis (TGA),  Fourier transform infrared spectroscopy (FTIR),  Atomic force microscopy (AFM), Brunauer –Emmet- Teller (BET) nitrogen adsorption method, Ammonia Temperature programmed desorption (NH3-TPD) and Scanning electron microscopy( SEM).  The effect of aging time, silica to alumina ratio is studied and the results sh

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Publication Date
Tue Jan 03 2023
Journal Name
College Of Islamic Sciences
Narrative Structures in the Novel “Qiamat Baghdad” for the Novelist Alia Talib – Semiotic Study
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Abstract

The human mind knew the philosophy and logic in the ancient times, and the history afterwards, while the semiotics concept appeared in the modern time, and became a new knowledge field like the other knowledge fields. It deals, in its different concepts and references, with the processes that lead to and reveals the meaning through what is hidden in addition to what is disclosed. It is the result of human activity in its pragmatic and cognitive dimensions together. The semiotic token concept became a knowledge key to access all the study, research, and  investigation fields, due to its ability of description, explanation, and dismantling. The paper is divided into two sections preceded by a the

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Publication Date
Wed Jun 11 2003
Journal Name
Iraqi Journal Of Laser
The Use of Pulse Frequency Modulation Technique for Optical Video Communication System
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An optical video communication system is designed and constructed using pulse frequency modulation (PFM) technique. In this work PFM pulses are generated at the transmitter using voltage control oscillator (VCO) of width 50 ns for each pulse. Double frequency, equal width and narrow pulses are produced in the receiver be for demodulation. The use of the frequency doubling technique in such a system results in a narrow transmission bandwidth (25 ns) and high receiver sensitivity.

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Publication Date
Tue Dec 11 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Assessment of Food Frequency Intake and Dietary Habits for Diabetic Pregnant Women
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Objective: The study aims at assessing the food frequency intake and dietary habits for diabetic pregnant
women.
Methodology: A descriptive study is carried out for the period from November4th 2013 to August
25th 2014. A purposive "non-probability" sample of one hundred diabetic pregnant women is selected from
the Diabetic and Endocrine Center in Al-Amarha City. A questionnaire is developed as a tool of data
collection. Content validity of the study instrument is determined through panel of experts. Split-half
reliability technique is used for reliability determination of the study instrument which depicts a reliability
coefficient of (0.79) for the entire scale. A structured interview with each diabetic pregnant wom

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Publication Date
Thu Oct 01 2009
Journal Name
High Performance Logistics: Methods And Technologies
High Performance Logistics
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Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Languages (jcl)
Symbolism in Nathaniel Hawthorne’s The House of the Seven Gables
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Nathaniel Hawthorne is famous for his psychological and moral themes. He is also famous for using symbolism in presenting his poignant themes of sin and its consequences. This research paper studies the use of symbols in Hawthorne's The House of Seven gables as an example of his general use of symbolism in his novels. The general pattern of Hawthorne's symbolism is that he presents one major symbol that embodies the main idea, and supports it with a number of minor symbols that develop and elucidate it. In The House of the Seven Gables, the major symbol is the house itself, which stands for corruption, evil, and the injustice of the past. This symbol is supported by such secondary symbols as the heart, the fountain, the

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Publication Date
Thu Nov 21 2019
Journal Name
Journal Of Engineering
Assessment of Observed Building Structure Setback of Shops along an Arterial Road and Noise Intrusion Level
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Roads irrespective of the type have specific standard horizontal distance measured at 90 degrees from a lot boundary to a development known as a setback. Non-observance of the recommended setbacks accommodated in any urban center’s master plan creates noise hazard to the public health and safety as the movement of vehicular traffic is not without the attendant noise. This study assessed noise intrusion level in shops along a section of Ibadan-Abeokuta road with due consideration to compliance with the recommended building structure setback. Analysis of noise descriptors evaluated in this study gave A-weighted equivalent sound pressure level average of 91.3 dBA, the daytime average sound level (LD) 92.27 dBA,

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Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Reduction of Noise and Vibration of Spur Gear by Using Asymmetric Teeth Profiles with Tip Relief
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Reduction of noise and vibration in spur gear experimentally by using asymmetric teeth profiles with tip relief was presented. Both of classical (symmetric) and asymmetric (with and without tip relief) spur gears are used in this work. Gear test rig was constructed to achieve torsional vibration measuring, and two modified cutters are designed and manufactured to achieve tooth profile modifications. First to cut asymmetric gear tooth with pressure angles (14.5o/25 o) without tip relief for loaded and unloaded tooth sides respectively, and second to cut asymmetric gear tooth with pressure angles (14.5o/25 o) for loaded and unloaded tooth sides respectively with tip relief to ach

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