The presentwork is a theoretical study in the field of charged particle optics. It concentrates on the design of electrostatic enzil lens for focusing charge particles beams, using inverse method in designingthe electrostatic lens. The paraxial ray equation was solved to obtain the trajectory of the particles, the optical properties such as the focal length and spherical and chromatic aberration coefficients were determined. The shape of the electrode of the electrostatic lens were determined by solving poison equation and the results showed low values of spherical and chromatic aberrations, which are considered as good criteria for good design.
A cantilever beam is made from composite material which is consist of (matrix: polyester) and (particles: Silicon-Carbide) with different volume fraction of particles. A force is applied at the free end of beam with different values. The experimental maximum deflection of beam which occurs at the point of the applied load is recorded. The deflection and slope of beam are analyzed by using FEM modeling. MATLAB paltform is built to assemble the equations, vector and matrix of FEM and solving the unknown variables (deflection and slope) at each node. Also ANSYS platform is used to modeling beam in finite element and solve the problem. The numerical methods are used to compare the results with the theoretical and experimental data. A good ag
... Show MoreThe present study includes a theoretical treatment to derive the general equations of pumping threshold power ( ), laser output power (Pout), and laser device efficiency (ƞ) of the element-doped thin-disk laser (Yb3+) with a quasi-three-level pumping scheme in the continuous wave mode at a temperature of (299K°). In this study, the host crystals (YAG) were selected as typical examples of this laser design in a Gaussian transverse mode. The numerical solution of these equations was made using Matlab software by selecting the basic parameters from the recently published scientific articles for the laser design of these crystal hosts. According to this simulation, this article studied the effect o
... Show MoreAbstract
This paper represents a study of the effect of the soil type, the drilling parameters and the drilling tool properties on the dynamic vibrational behavior of the drilling rig and its assessment in the drilling system. So first, an experimental drilling rig was designed and constructed to embrace the numerical work.
The experimental work included implementation of the drill-string in different types of soil with different properties according to the difference in the grains size, at different rotational speeds (RPM), and different weights on bit (WOB) (Thrust force), in a way that allows establishing the charts that correlate the vibration acceleration, the rate of penetration (ROP), and the power
... Show MoreIn this paper, the theoretical cross section in pre-equilibrium nuclear reaction has been studied for the reaction at energy 22.4 MeV. Ericson’s formula of partial level density PLD and their corrections (William’s correction and spin correction) have been substituted in the theoretical cross section and compared with the experimental data for nucleus. It has been found that the theoretical cross section with one-component PLD from Ericson’s formula when doesn’t agree with the experimental value and when . There is little agreement only at the high value of energy range with the experimental cross section. The theoretical cross section that depends on the one-component William's formula and on-component corrected to spi
... Show MoreThis work is concerned with a two stages four beds adsorption chiller utilizing activated carbon-methanol adsorption pair that operates on six separated processes. The four beds that act as thermal compressors are powered by a low grade thermal energy in the form of hot water at a temperature range of 65 to 83 °C. As well as, the water pumps and control cycle consume insignificant electrical power. This adsorption chiller consists of three water cycles. The first water cycle is the driven hot water cycle. The second cycle is the cold water cycle to cool the carbon, which adsorbs the methanol. Finally, the chilled water cycle that is used to overcome the building load. The theoretical results showed that average cycle cooling power
... Show MorePurpose: studying and analyzing the nature of uncertainty as part of strategy formulation, through analyzing the uncertainty faced by managers in the modern business environment characterized by high complexity and dynamism, though developing of an idea about the uncertainty cases and how enable the mind to understand these cases.
Methodology: It was the use of inductive and analytical approach, in order to study the accumulation of knowledge towards development areas that could contribute to strengthening the strategy formulation.
Findings: Mentoring the future will not make the success for business organization but thought business organization ability to developing share mental
... Show MoreThis research tackles the semantic function of colors in the poetry of Gada Al Samman, in the introduction the research explores the difference in the semantic colors for people and the function of these colors in arising the feelings for the human spirit and its influence on that spirit. The research tackles the poems of this poetess that are full of symbolic colors that convey positive and negative meanings related to the poetess herself. In addition the research shows the functions of colors in her poetry through the compatibility of colors by employing colors in her poetry in terms of compatibility with the vision of community to denote colors. Beside using the function of colors contrast by employing the colors in different meaning
... Show MoreThis study attempts to focus on there lation ship between employment policies andsocietal changesinIraq.Theconstruction ofoperational policyincommunitiesin crisis remains fraught with challenges and risks, especially in countries that have longoutstanding conflict sand crises, it is important in this context to achieve those policy and build the foundations of human security and poverty alleviation, unemployment, to find effective ways to help the community to achieve stability and reduce the risk of renew edorrepeat the cycleofviolence-butthatwouldrequirearadicalrethinking, including rethinking the way evaluating therisksandchallengesand management.And thatsuchaprojectshouldbe based ona clear roadmap, andthevisionsofdevelopmentanda clea
... Show MoreThe sunna has the great effect in building the Islamic civilization, and the formulation of the Islamic thinking. It worked at spreading of soicinces at every district of Islam. The purified sunna represent one of the main monuments of Islam after Quran in clarifying the basics of the human intercommunication, and the divine reality. It comes as an explanation to the myertious accounts in the shariaa and sunna that it has begun to form an intellectual depth of the Mulsims' life. The importance ofsunna is it is the second source of legislation in Islamic after the holt Quran. It comes only to affirm what have been mentioned already in theHoly Quran, or clarifying what is not clear in the Quran.
The Maghreb Did not know modern problem more complex and dangerous than the problem of Western Sahara, which is the first obstacle in front of building Arab Maghreb, did not enter Post-independence governments in attrition mutual since liberation wars until today, as happened with this problem between Morocco and Algeria supporting the Polisario Front separatist and did not know the end after so, this research focused on the show dimensional geopolitical to this problem and reveal the role of regional and international behind its continuation and the latest developments after the revolutions Arab Spring and its impact on the problem and the end of UN mission new to the Sahara and results.