Preferred Language
Articles
/
bsj-2666
Space-Charge Effect on the Theoretical Design of Electron Gun Operated under Zero Magnification Condition
...Show More Authors

A computational investigation is carried out in the field of charged –particle optics with the aid of numerical analysis method using the personal computer. The work is concerned with the design of electron gun with space-charge effect. The Finite element method (FEM) used in the solution of Poison's equation for determine the axial potential distribution of the two-electrode immersion lens operated under zero magnification condition , and from the solution of the paraxial ray equation the optical properties such as the focal length , spherical and chromatic aberration coefficients are determined, also a calculation of the brightness and perveance for the lens. The electrodes geometry was determined in two and three dimension with the aid of new drawing software called SIMION 7 and the electron beam trajectory under zero magnification conditions has been determine for these electrodes.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Effect of Polymers on Permanent Deformation of Flexible Pavement
...Show More Authors

The permanent deformation of flexible pavement represent serious problem in hot climate region. Numerous efforts are devoted to mitigate this distress such as modifying asphalt binder by polymers. The present study demonstrate the effect of utilizing four types of polymers to reduce the permanent deformation, these polymers are Polyethylene Wax (PEW), Styrene Butadiene Rubber (SBR), Ethylene Propylene Dien Monomer (EPDM) and Ethylene Vinyl Acetate (EVA). The prepared mixtures composed of 4.9 % of 40/50 asphalt binder, 12.5 mm nominal aggregate maximum size and limestone dust as filler. The permanent and resilient strains have been recorded when the cylindrical specimens, 101.6 mm in diameter and 203.2 mm in height, tested by repeated loa

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Sep 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Effect of Additives on Rheological Properties of Invert Emulsions
...Show More Authors

This research deals with study of the effect of additives on rheological properties (yield point, plastic viscosity ,and apparent viscosity) of emulsions. Twenty seven emulsion samples were prepared; all emulsions in this investigation are invert emulsions when water droplets are dispersed in diesel oil. The resulting emulsions are called water-in-oil (W/O) emulsions. The rheological properties of these emulsions were investigated using a couett coaxial cylinder rotational viscometer (Fann-VG model 35 A), by measuring shear stress versus shear rate. It was found that the effect of additives on rheological properties of emulsions as follow: the increase in the concentration of asphaltic material tends to increase the rheological propertie

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
Effect of Biopolymer Alginate on some properties of concrete
...Show More Authors

Alginate from Large brown seaweeds act as natural polymer has been investigated as polymer and has been added to concrete in different percentages ( 0% , 0.5% , 1% and 1.5% ) by the cement weight and the study show the effect of using alginate biopolymer admixtures on  some of the fresh properties of the concrete (slump &  the density  fresh) also in the hardened state (  Compressive strength , Splitting tensile strength  and Flexural strength ) at 28 days. The mix proportion was (1:2.26:2.26) (cement: sand: gravel) respectively and at constant w/c equal to 0.47. The results indicate that the use of alginate as a percent of the cement weight possess a positive effect on fresh properties of co

... Show More
View Publication Preview PDF
Crossref (7)
Crossref
Publication Date
Mon Oct 01 2018
Journal Name
International Journal Of Civil Engineering And Technology
NUMERICAL ANALYSIS OF PILES FOUNDATION TO REDUCE THE ZONE OF LIQUEFACTION OF SANDY SOIL UNDER DYNAMIC LOADS
...Show More Authors

The major cause of destruction during vertical vibration is the failure of the soil structure. The soil may fail due to loss of strength during continues vibration. The saturated sandy soil losses strength due to an increase in pore pressure, this phenomenon is called "liquefaction". Piled foundations are usually adopted as a foundation solution in potentially liquefiable soil under dynamic loading. In this research, 3D finite element model using PLAXIS Software was employed for pile foundation in saturated sandy soil. The results show the acceleration mobilization and velocity on the footing increases with increasing the intensity of dynamic loads and it becomes zero at maximum value of vertical settlement which indicates the end of the ti

... Show More
View Publication Preview PDF
Publication Date
Thu Mar 01 2018
Journal Name
Journal Of Engineering And Sustainable Development
MEASURING THE URBAN INTEGRAL SUSTAINABILITY IN “MUSTANSIRIYA UNIVERSITY “ACCORDING TO THE INTEGRAL DESIGN THEORY
...Show More Authors

View Publication
Crossref
Publication Date
Sun Mar 20 2016
Journal Name
Al-academy
The Floors and transparent role in the design studios satellite channels: وسام صالح حمد
...Show More Authors

The search (floors and transparent role in the design studios satellite channels) and presented as a study-oriented, and the research aims to identify the role of flooring transparent spaces studios satellite channels and side performative and aesthetic, and formulas design to highlight the role floors transparent spaces studios satellite channels. And highlight the importance of research, particularly in its contribution to the clarification of the concept of the relationship between transparency and performing aesthetic treatments for floors by clarifying its role in the designs of the internal spaces of the studios, as well as his contribution to the founding of the theory of looking at the base of such concepts. To achieve the object

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Technological Change in Process Design Decisions (Applied study in an organization)
...Show More Authors

Abstract:

     Due to the importance of technology and the accompanying changes of the environment affecting companies that use the technology mainly in their work, especially as most companies live in an unstable dynamic environment, which motivated the researchers to choose the International Company for smart card (Keycard) as a field of research and find ways to them to face Those changes.

     The problem of the study was "limited attention to the components of technological change", which included research and development, innovation and information technology, which had an impact on the design decisions of the process (process selection, cust

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Dec 16 2020
Journal Name
Electronics
Downlink Training Design for FDD Massive MIMO Systems in the Presence of Colored Noise
...Show More Authors

Massive multiple-input multiple-output (MaMi) systems have attracted much research attention during the last few years. This is because MaMi systems are able to achieve a remarkable improvement in data rate and thus meet the immensely ongoing traffic demands required by the future wireless networks. To date, the downlink training sequence (DTS) for the frequency division duplex (FDD) MaMi communications systems have been designed based on the idealistic assumption of white noise environments. However, it is essential and more practical to consider the colored noise environments when designing an efficient DTS for channel estimation. To this end, this paper proposes a new DTS design by exploring the joint use of spatial channel and n

... Show More
View Publication
Scopus (15)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Wed Dec 15 2021
Journal Name
Al-academy
Simulation of myths in industrial product design "the seven eyes amulet as a model"
...Show More Authors

The research is to identify the legend of the seven eyes amulet of Babylonian origin and the representations it carried of the link between the Babylonian past and the Islamic present presented in the design works of the promoted products, preserving its impact in the souls as a way to avoid the act of envy, and from this was the research problem that I want to get answers to, which That is (How was the legend of the seven-eyes amulet represented in the design of industrial products?), making its goal to identify how that legend was represented within the design work of marketed industrial products, and in order to reach the answer, the research presented many concepts starting with the legend in its various forms in industrial products.

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Design of Achromatic Combined Quadrupole Lens Using the Modified Bell-Shaped Field Distribution Model
...Show More Authors

The optimization calculations are made to find the optimum properties of combined quadrupole lens consist of electrostatic and magnetic lenses to produce achromatic lens. The modified bell-shaped model is used and the calculation is made by solving the equation of motion and finding the transfer matrices in convergence and divergence planes, these matrices are used to find the properties of lens as the magnification and aberrations coefficients. To find the optimum values of chromatic and spherical aberrations coefficients, the effect of both the excitation parameter of the lens (n) and the effective length of the lens into account as effective parameters in the optimization processing

View Publication Preview PDF