A theoretical study to design a conformal microstrip antennas was introduced in this work. Conformal microstrip antennas define antennas which can be conformed to a certain shape or to any curved surface. It is used in high-speed trains, aircraft, defense and navigation systems, landing gear and various communications systems, as well as in body wearable. Conformal antennas have some advantages such as a wider-angle coverage compared to flat antennas and low radar cross-sectional (RCS) and they are suitable for using in Radome. The main disadvantage of these antennas is the narrow bandwidth. The FDTD method is extremely useful in simulating complicated structures because it allows for direct integration of Maxwell's equations depending on time. The 1x2 cylindrical circular microstrip antennas array is designed and simulated vertically via Finite Difference Time Domain (FDTD) method where can directive antenna be achieved through antennas array design. Mutual coupling between the antennas in the array and the different separation between them were studied. The circular patch is excited by a probe feed method for several reasons including providing less spurious radiation from the probe current, in addition to the simplicity in theoretical engineering installation and practical manufacturing. It is well known that the values of the coupling are decreased as the distance separation increased. Cylindrical circular microstrip antenna with resonant frequency operating is 3.5GHz for mode, several parameters like return loss, band width, and input impedance are calculated. Also, for isolated coupling, mutual coupling coefficients, directivity gain, for different separations between the centers of the two adjacent circular patches in terms the wave length operating are calculated. Moreover, the electromagnetic band gap EBG structure is used for reducing the mutual coupling created by the surface waves in order to enhance the antenna's performance in an array has become smaller than before. The proposed EBG is a three triangular-shape equal sides metallic structure, utilizing the inter-element spacing in an array. The less value of for the spacing between the two centers of patches is . BW percentage increased to 34.3% and the directivity is enhanced also. Additionally, simulations were done using MATLAB 2017b.
The results of analyzing BVRI CCD photometry of the spiral galaxies NGC 7339, NGC 7537, and NGC 7541 are presented using the observations acquired with the 1.88m Kottamia telescope (Egypt). The overall structure of the galaxies is analyzed together with isophotal contour maps. The surface brightness profiles of the galaxies are decomposed to bulge and disk components by fitting a de Vaucouleurs law for the bulge and an exponential law for the disk to obtain photometric parameters for each component. The corrected total and absolute magnitudes and integrated color are also obtained and found to be close to the published values. The radial profiles of ellipticity, major-axis position angle, and color are also obtained and discussed.
Background: The pandemic crisis prompted the world to adopt unexpected approaches to continue life as normally as possible. The education sector, including professors, students, and the overall teaching system, has been particularly affected. Objective: This study seeks to evaluate the benefits, challenges, and strategies related to COVID-19 from the perspectives of college students, particularly those in higher education in Iraq. Method: The online survey questionnaire was distributed via Google Forms and specifically aimed at undergraduate dental students. Results: A total of 348 students participated in the survey. There was a significant correlation (P > 0.01) between student satisfaction with hybrid learning and their experi
... Show MoreAchieving high achievement in the sport of fencing requires thinking, awareness and visual tracking, as visual tracking is one of the important visual abilities that a fencing player needs and is considered one of the special visual abilities as it contributes and helps in the correct motor, mental and mental performance and gives the fencing the ability to perfect and accomplished performance in training and competition. Where the research problem lies in the weak skill performance of the fencing players as a result of the weakness in possessing visual and mental abilities. The two researchers used the experimental method in a controlled manner (experimental and control groups) with a pre and post-test. The research community was identifie
... Show MoreComplex and complex psychological processes are complexand are the result of convergence, convergence and interaction between variables, including the subject of mediation or group or individual and psychological processes involved in the variance, including - personal knowledge and emotional tone (Osman, 1987, p. 8 ). An emotionally balanced individual has the ability to endure and delay meeting needs and has the ability to endure as much as possible. Of the emotional balance of the individual is characterized by emotional stability, show some signs of emotional agitation toward any kind of opposition, anger and realism in self-life and discipline (Swift, 1996, p. 44) Van, et al. , Indicates that people with low emotional balance,
... Show MoreMessage in the tune of readers and denial to those who say infidelity tunes
Abstract
The extremes effects in parameters readings which are BOD (Biological Oxygen Demands) and DO(Dissolved Oxygen) can caused error estimating of the model’s parameters which used to determine the ratio of de oxygenation and re oxygenation of the dissolved oxygen(DO),then that will caused launch big amounts of the sewage pollution water to the rivers and it’s turn is effect in negative form on the ecosystem life and the different types of the water wealth.
As result of what mention before this research came to employees Streeter-Phleps model parameters estimation which are (Kd,Kr) the de oxygenation and re oxygenation ratios on respect
... Show MoreThe present study focuses on the deformation of neutron-rich nuclei near the neutron drip line. The nuclei of interest include 28O, 42Si, 58Ca, 80Ni, 100Kr, 122Ru, 152Ba, 166Sm, and 176Er. The relativistic Hartree - Bogoliubov (RHB) approach with effective density-dependent point coupling is utilized to investigate the triaxial deformation, and Skyrme - Hartree - Fock + Bardeen - Cooper - Schrieffer is used to analyze the axial deformation. The study aimed to understand the interplay between nuclear forces, particle interactions, and shell structure to gain insights into the unique behavior of neutron-rich nuclei. Despite these nuclei containing magic numbers, their shapes are still affected by the nucleons' collective behavior and
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