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.
The research aims to study the contribution of tax information systems to increase tax revenues, and to identify how efficiently used information systems currently by the tax authority and their effectiveness in the detection of irregularities by the tax payers such as the cleclaration of incorrect statements that do not show real results of their business activities or hide information from sources related to their income subject to tax, which would negatively affect the outcome of tax revenues and thus damage important sourse of the public treasury of the states resources. The data of research was collected by studying and analysing the tax information systems used by the General Commission of taxs and its branches and a number of prac
... Show MoreThin films of ZnSe arc deposited on glass substrates by thermal evaporation in vacuum with different thickness (1000, 2700, 4000) A° temperature (293-373) °K are studies the electrical properties before and after annealing. The result show decrease D.0 conductivity and increasing the activation energy Eat.
The progress of science in all its branches and levels made great civilized changes of
our societies in the present day, it's a result of the huge amount of knowledge, the increase of
number of students, and the increase of community awareness proportion of the importance of
education in schools and universities, it became necessary for us as educators to look at
science from another point of view based on the idea of scientific development of curricula
and teaching methods and means of education, and for the studying class environment as a
whole, by computer and internet use in education to the emergence of the term education
technology, which relies on the use of modern technology to provide educational content to<
Background: The use of the cone beam computed tomography for analysing the position of the greater palatine foramen in relation to various anatomical landmarks is crucial in dentistry. The aims of the current study, firstly is to determine the greater palatine foramen position in relation to various anatomical landmarks by using cone beam computed tomography and secondly is to make a comparison of the measurements according to side, gender, and age. Materials and methods: This prospective study included 60 Iraqi patients (28males and 32 females) who selected according to availability of Inclusion criteria, which include age range (21 - 60 years), with no dentofacial deformities or pathological lesion at the maxilla. All patients had inform
... Show MoreThe oxidative degradation of Orange G dye by nanosized CeO2 catalyst has been performed in this study. The catalyst was prepared by precipitation method. Various characterization techniques were carried out to study the physical and chemical properties of the synthesized catalyst. The XRD result confirms well the formation of CeO2 cubic phase. The FTIR result showed the effect of calcination temperature for CeO2 was clearly observed due to reduction in band intensity compared to uncalcined Ce nitrate sample. Meanwhile, the diffused reflection spectra recorded reflection spectra at 414 nm with an energy gap of 3.2 ev. The decolorization of Orange G dye by oxidation process were carried out unde
... Show MoreThe present study aims at knowing the effect of instrumental enrichment in the acquisition of geographical concepts for first grade student in intermediate school. The study is restricted in the students of first grade student in intermediate school\ The EducationalDirectorate of Rusafa for academic (2013/2014),for the purpose of achieving the objective, the following hypotheses:
There is no statistical significant different at the level of (0.5) between the scores of the experimental group who study geography according to the instrumental enrichment and the scores of the control group who learned geographical according to the traditional methods.
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... Show MoreThe researchers in this study, which aimed to find out Degree contribution of Iraqi
women in development from the perspective faculty members of the complex Jadriya
University in Baghdad, and the the impact of demographic variables (gender, college, place of
living, school level,) for its contribution.
The study population consisted of some faculty members Jadiriyah compound in
Baghdad's University for the academic year 20012/2013. This study followed a descriptive
approach the field, and the analytical method, the study sample consisted of (250) teaching all
of College of Science for girls and education for girls, and to achieve objective of the study
was the development of a questionnaire, was sure of its sincer
The research Reviews the sides of highlight importance of the Nano-Accounting which doing the accounting performance functions fully computerized without the intervention of an accountant, to solve the problem of not keeping up the rationalization of recording and accounting systems, with the rationalization of production which fully computerized.(be invisible and hidden accounting), resulting by linking or interaction of the accounting, additive production system represented three-dimensional printers, open source and recycling. That which result the rationalizing the facilities of production, organization and self-control which derived nanotechnology idea, which aims to minimize materials and change it properties, then view the a
... Show MoreThe present study aimed at identifying the level of psychological alienation and motivation of achievement among the incoming teachers in the schools of Dhofar Governorate in the Sultanate of Oman a well as to explore the correlation relationship between psychological alienation and motivation of achievement. The sample of the study consisted of (238) expatriated teachers from Al- Dhofar Governorate in Oman who were selected randomly. The psychological alienation scale and the motivation of achievement scale for teachers were used by researchers and were conducted electronically by google forms. The data were processed statistically using the Statistical Package for Social Sciences (SPSS). The results showed that the level of psy
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