A numerical computation for determination transmission coefficient and resonant tunneling energies of multibarriers heterostructure has been investigated. Also, we have considered GaN/Al0.3Ga0.7N superlattice system to estimate the probability of resonance at specific energy values, which are less than the potential barrier height. The transmission coefficient is determined by using the transfer matrix method and accordingly the resonant energies are obtained from the T(E) relation. The effects of both well width and number of barriers (N) are observed and discussed. The numbers of resonant tunneling peaks are generally increasing and they become sharper with the increasing of N. The resonant tunneling levels are shifted inside the well by increasing the well width and vice versa. These features and the transmission coefficient as a function of incident energetic particles play an important role in fabrication of high speed devices and a good factor for determination the peak-to-valley ratio of resonant tunneling devices respectively.
Twilight is that light appear on the horizon before sunrise and after sunset, Astronomically it is known that sunrise and sunset are effected by high above sea level, but the effect of high above sea level on the time of astronomical twilight still not decided and controversy among astronomers, in This research we studies the effect of high above sea level on the time of astronomical twilight, through adding the equation correct high above sea level to equation computation of twilight and then calculate of changing in the time of twilight for different highest (0-10000) meters above sea level , and the ratio of increase for time with high between (15.45-20.5) minutes. It was found that there was an increase in the time of the twilight along
... Show MoreAl-Wasiti's drawings are the first attempt to document the Arab landscape more than 778 years ago. These drawings were associated with a fine literary material, and the relationships between words and poetic sentences are matched by artistic, aesthetic and color relations in drawing, as they are all outputs of a sense that agreed in creativity and differed in the language of expression. Al-Wasiti was creative in drawing these events. Islamic painting has a goal that differs from the goals of the painting arts that preceded it or its contemporary, as it tends to “beautification” only. This is achieved by true copying from nature, just as it is achieved by drawing what is transmitted from nature, transforming and refining it. The
... Show MoreFour metal compounds mixed ligand of azo dye ligand (L) and metformin.(Met) were produced at aquatic ethanol for (1:1:1) (M:L:Met). The prepared compounds were identified by utilizing atomic absorption flame, FT.IR and UV–Vis spectrum manners as well as conductivity mensuration. These compounds was assayed of the gained datum the octahedral geometry was proposed into whole prepared complexes.Also in this research was studied represented examining the antibacterial and antifungal impact of the azo dye ligand (L), metformin.(Met) and (Co,Ni, Cu and Cd complexes) on four types of pathogenic, clinically isolated bacteria that are resistant to antibiotic, like Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneu
... Show MoreThis paper is submitted as anew approach to simulate manufacturing control & planning system to define the problem of designing control system on the needs for materials.
Production planning & control is a total and complex operation, resides in the essence of manufacturing companies operations. The successful process of production planning and control systems is critical for the staying of manufacturing organizations in markets leading to the increasing consumer competition and which dominate most of manufacturing sectors because of the market oriented economy , thus , what has happened previously , that the companies possessed a great inventory of crude material, components, and groupings and they use in flexible techni
... Show MoreThe attention of civil society organizations, governments and international non-governmental organizations in recent years has focused on the acute practices adopted by companies with the aim of reducing the tax burden, and the results of these practices have a negative impact on the tax revenues that the state uses to finance public needsThe aim of the research is to measure the impact of the voluntary disclosure of companies on tax planning for the period from 2011 to 2015 and the research community is in the General Tax Authority. The research sample is 6 companies within the private sector in the financial, banking, insurance and industrial fields. The research was based on a special model to measure the optional disclosure,
... Show MoreThe aim of this study was to measure the effectiveness of a proposed program to develop the creative abilities of the students of Tabuk University and its impact on the creative output of the NEOM project. The sample of the study consisted of (50) university students divided into two groups: an experimental group of 25 students who receive the proposed training program, and control group of (25) students.
To achieve these objectives, the researcher designed and developed tools to collect the required data, which were verified their validity and reliability.
The descriptive statistics of mean, standard deviations, correlation coefficient, T test for the associated sample were used in the analysis of the results of th
... Show Moreولاء طارق حميد, Mustansiriyah Journal of Sports Science, 2021