Preferred Language
Articles
/
alkej-29
Design & Implementation of High Switching & Low Phase Noise Frequency Synthesizer

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Apr 05 2015
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Evaluation of the Effects of Surgical Varicocelectomy on the Seminal Fluid Parameters in Patients with Clinical and Subclinical Varicocele

Backgound: Varicoceles defined as abnormally dilated testicular veins (pampiniform plexus) of in the scrotum and it is found in approximately 15% of the general population and associated with adverse effects on the seminal fluid and fertility. According to size of that blood vessels; the varicocele is divided into clinical that are discovered in physical examination and subclinical that are only discovered by Doppler examination. It is well known that clinical varicocele affect the seminal fluid and always treated surgically as a part of treatment of infertility or because of pain or cosmetic purpose but the controversy is about the cases of subclinical varicocele and the indication of surgery and its outcome.
Objective: To assess the

... Show More
Crossref
View Publication Preview PDF
Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Using modern techniques for determining the location of marketing outlet for product of the state company for vegetables oil

Were arranged this study on two sections, which included first section comparison between markets proposed through the use of transport models and the use of the program QSB for less costs , dependant the optimal solution  to chose the suggested market  to locate new market that achieve lower costs in the transport of goods from factories (ALRasheed ,ALAmeen , AlMaamun ) to points of sale, but the second part has included comparison of all methods of transport (The least cost method ,Vogels method , Results Approximations method , Total method) depending on the agenda of transport, which includes the market proposed selected from the first section and choose the way in which check the solution first best suited in terms

... Show More
Crossref
View Publication Preview PDF
Publication Date
Mon Oct 22 2018
Journal Name
Journal Of Economics And Administrative Sciences
Measuring and analyzing the relationship between the volatility of US stock market indices and the volatility of oil prices

The volatility of the financial markets and the oil market plays a major role in influencing macroeconomic activity, as well as the high interaction between the both markets and the remarkable sensitivity to their each other fluctuations which cause the undesirable impact on other economic sectors as an expected result due the mentioned interaction.

The study aimed to analyze the relationship between the volatility of the major US market indices represented by the DJIA index, S & P500, due to their comprehensiveness of the financial market, as they summarize the performance of the entire US market which is the largest economy in the world, as well as the difference in the calculation mechanism, and oi

... Show More
Crossref (1)
Crossref
View Publication Preview PDF
Publication Date
Mon Feb 25 2019
Journal Name
Iraqi Journal Of Physics
Effects of multi- Deposition on the structural and optical properties of CdS nanocrystalline thin film prepared by CBD technique.

Cadmium sulfide (CdS) nanocrystalline thin films have been prepared by chemical bath deposition (CBD) technique on commercial glass substrates at 70ºC temperature. Cadmium chloride (CdCl2) as a source of cadmium (Cd), thiourea (CS(NH2)2) as a source of sulfur and ammonia solution (NH4OH) were added to maintain the pH value of the solution at 10. The characterization of thin films was carried out through the structural and optical properties by X-ray diffraction (XRD) and UV-VIS spectroscopy. A UV-VIS optical spectroscopy study was carried out to determine the band gap of the nanocrystalline CdS thin film and it showed a blue shift with respect to the bulk value (from 3.9 - 2.4eV). In present w

... Show More
Crossref
View Publication Preview PDF
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
The reality of the colleges of education in quality assurance for professors teaching methods in educational and psychological science

     That achieve a level of excellence for the quality of university education cannot be achieved only by uniting the efforts of all employees at the university and active participation by students and by alumni and the labor market and society, however we can say that the administrative and academic  university staff play an active role and the largest in achieving equivalent quality of higher education, It should unite the efforts of all employees in the educational institution in order to achieve quality education. It is the concept of quality of education, quality assurance and overall management of the quality of the basic pillars on which it is based university education. That highlight the need fo

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 01 2010
Journal Name
Iraqi Journal Of Physics
The effect of anode temperature on the Optical characteristic of Se films prepared by direct current planar magnetron sputtering

This work describes, selenium (Se) films were deposited on clean glass substrates by dc planar magnetron sputtering technique.The dependence of sputtering deposition rate of Se film deposited on pressure and DC power has been studied. The optimum argon pressure has range (4x10-1 -8x10-2 )mbar. The optical properties such as absorption coefficient (α) was determined using the absorbance and transmission measurement from UnicoUV-2102 PC spectrophotometer, at normal incidence of light in the wavelength range of 200-850 nm. And also we calculated optical constants(refractive index (n), dielectric constant (εi,r), and Extinction coefficient (κ) for selenium films.

View Publication Preview PDF
Publication Date
Thu Jan 31 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Strategic Management of Cost of Production Operations In the 0il Fields: بحث تطبيقي في شركة نفط الوسط (شركة عامة)

The use of the entrance diffraction hexagon continuous improvement of operations in order to achieve the rationalization of activities, costs and efficiency in the use of available resources and reduce the incidence of damage and waste and recycling, as the accounting information system does not meet the surface production processes oil fields cost management requirements in the measurement and evaluation of the costs of each activity and development of indicators to evaluate the efficiency and effectiveness of production processes and to cover the shortcomings of currently approved by the company so cost accounting system has Find addressed the use of strategic cost management techniques, including the entrance diffraction hexagon for c

... Show More
Crossref
View Publication Preview PDF
Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Educational And Psychological Researches
Employing electronic supervision applications in developing the teaching performance of teachers in the Sultanate of Oman: a suggested vision

The study aimed to investigate the employment of electronic supervision applications in developing the teaching performance of teachers in Oman. Based on the qualitative method and the study population consisted of all the teachers of the first cycle in the Governorate of Muscat. The study sample amounted to 24 female teachers. The interview was used as a tool for data collection. The study reached several results, including: There are difficulties in employing electronic supervision applications, which are weak network, density of curricula, lack of experience in applying technology, and the large number of tasks assigned to the teacher. These difficulties can also be overcome by strengthening the network, training teachers, reducing th

... Show More
View Publication Preview PDF
Publication Date
Sat Sep 15 2018
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation of Anti-Centromere Antibodies, Anti-SSA and Anti-SSB in Serum and Saliva of Patients with Systemic Sclerosis

Background: Systemic sclerosis (SSc) is a chronic autoimmune illness, which is consider by three main features: Sclerotic changes in the skin and internal organs, Vasculopathy of small blood vessels, Particular autoantibodies (1). The most important autoantibodies appeared significantly in SSc patients are anti-topoisomerase I autoantibody (Scl-70), anti-centromere autoantibody (ACA), and anti-RNA polymerase III autoantibody (RNAP3) (2). Anti-centromere antibodies (ACA) are infrequent in rheumatic conditions and in healthy persons but occur commonly in limited systemic sclerosis (CREST syndrome), and rarely appeared in the diffuse form of systemic sclerosis (3). Anti-Ro/SSA and antiLa/SSB, antibodies directed against Ro/La ribonucleoprot

... Show More
Crossref
View Publication Preview PDF
Publication Date
Wed Mar 30 2022
Journal Name
Iraqi Journal Of Science
Impact of Varying Viscosity with Hall Current on Peristaltic Flow of Viscoelastic Fluid Through Porous Medium in Irregular Microchannel

    In this article the peristaltic transport of viscoelastic fluid through irregular microchannel under the effect of Hall current, varying viscosity and porous medium is investigated. The mathematical expressions for the basic flow equations of motion are formulated and transformed into a system of ordinary differential equations by utilizing appropriate non dimensional quantities. The exact solution for the temperature distribution is obtained, while perturbation series solution for the stream function in terms of tiny viscosity parameter is used. Graphical illustrations are  presented to capture the physical impact of embedded parameters in the fluid flow i.e. the fluid velocity field, temperature distribution, pressure rise, and

... Show More
Scopus (4)
Crossref (1)
Scopus Crossref
View Publication Preview PDF