The Maxwell equations have been formulated for a composite slab waveguide at x-band wave propagation. The eigenvalues of the system equations are obtained by using MATLAB program. These eigenvalues are used to obtain the wave propagation constant and a number of modes inside the slabs. A good correspondence was seen between the number of modes and the cut off thickness. The parameter that affects the performance of waveguide is the slab thickness. The propagation constant is usually adopted to characterize this type of waveguide and show how the cutoff frequency of the mode in the slab is increased dramatically by decreasing the frequency.
Our study focused on lower modes, the results for the transmission coefficient are then used to study the propagation properties of the guided modes in waveguides. Characteristic equations, solutions for TE (transverse electric) modes are presented. Numerical results for the propagation constant and field distributions of several lower-order modes are presented.
By finding the exact transmission coefficient of lower mode of a plane wave incident at a normal incidence on composite slabs, the propagation properties of guided modes in planar slab were studied.
It is important to find suitable materials for the transmitting and receiving of microwave frequencies and useful for designing a waveguide filter to separate waves of the same frequency but with different transmission modes.
The research has tackled about an important transformation within the whole region of middle east, especially there were more challenges which revealed under the huge pivotal interests of global powers that ruled the new world order by United states of America ; being very affected over the international and regional relations than any situations appeared previously within political realities. So that, many of variables inside the international scene which happened during of this period of contradicting strategic policies by the process of reforming and restructuring of difficult equations that imposed by international and regional allies and blocs . This article had concentrated over various strategic and political studies which reflect
... Show MoreBimetallic Au –Pt catalysts supporting TiO2 were synthesised using two methods; sol immobilization and impregnation methods. The prepared catalyst underwent a thermal treatment process at 400◦ C, while the reduction reaction under the same condition was done and the obtained catalysts were identified with transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS). It has been found that the prepared catalysts have a dimension around 2.5 nm and the particles have uniform orders leading to high dispersion of platinum molecules .The prepared catalysts have been examined as efficient photocatalysts to degrade the Crystal violet dye under UV-light. The optimum values of Bimetallic Au –
... Show MoreThe process of evaluating data (age and the gender structure) is one of the important factors that help any country to draw plans and programs for the future. Discussed the errors in population data for the census of Iraqi population of 1997. targeted correct and revised to serve the purposes of planning. which will be smoothing the population databy using nonparametric regression estimator (Nadaraya-Watson estimator) This estimator depends on bandwidth (h) which can be calculate it by two ways of using Bayesian method, the first when observations distribution is Lognormal Kernel and the second is when observations distribution is Normal Kernel
... Show MoreBiodiesel production process was attracted more attention recently due to the surplus quantity of glycerol (G) as a byproduct from the process. Glycerol Utilization must take in to consideration to fix this issue also, to ensure biodiesel industry sustainability. Highly amount of Glycerol converted to more benefit material Glycerol carbonate (GC) was one of the most allurement compound derived from glycerol by transesterification of glycerol with dimethyl carbonate (DMC). Various parameters have highly impact on transesterification was investigated like catalyst loading (1-5) %wt., molar ratio of DMC: glycerol (5:1 – 1:1), reaction time (30 - 150) min and temperature (40 – 80) ᴼC. The Optimum glycerol carbonate yie
... Show MoreThe service system has become a necessity of life in modern cities to be the most basic necessities of modern humans, they constitute a major base, which is based on the sustainability of life in the city and a standard measured through the degree of well-being and progress of civilized peoples and their interaction with the surrounding environment, making the services sector as a need not be an option, whenever the cities widened in population and space whenever provision of services and upgrading the quality and quantity more pressing, which made the subject of the services takes the biggest area of the trends and thinking of urban planners and those who in charge of drawing the cities policies. Consideri
... Show MoreThe Frequency-hopping Spread Spectrum (FHSS) systems and techniques are using in military and civilianradar recently and in the communication system for securing the information on wireless communications link channels, for example in the Wi-Fi 8.02.X IEEE using multiple number bandwidth and frequencies in the wireless channel in order to hopping on them for increasing the security level during the broadcast, but nowadays FHSS problem, which is, any Smart Software Defined Radio (S-SDR) can easily detect a wireless signal at the transmitter and the receiver for the hopping sequence in both of these, then duplicate this sequence in order to hack the signal on both transmitter and receiver messages using the order of the se
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Patient aggression is a global health care problem. This study examined the impact of patient aggression on the quality of care that patients receive as perceived by their family members and the ethical challenges involved from the nurse’s perspective. A descriptive–analytical method was used. The participants of this study were nurses working on psychiatric units and family members of patients in Iraq. Two questionnaires were used: one on nursing care quality and one on ethical challenges in clinical situations. The results showed that the quality of care for these patients was reduced, with a