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bsj-7050
Reducing the Mutual Coupling of Cylindrical Circular Microstrip Antennas (CCMAs) Array Using EBG Structure
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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.

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Publication Date
Tue Dec 01 2020
Journal Name
Baghdad Science Journal
A Modified Support Vector Machine Classifiers Using Stochastic Gradient Descent with Application to Leukemia Cancer Type Dataset
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Support vector machines (SVMs) are supervised learning models that analyze data for classification or regression. For classification, SVM is widely used by selecting an optimal hyperplane that separates two classes. SVM has very good accuracy and extremally robust comparing with some other classification methods such as logistics linear regression, random forest, k-nearest neighbor and naïve model. However, working with large datasets can cause many problems such as time-consuming and inefficient results. In this paper, the SVM has been modified by using a stochastic Gradient descent process. The modified method, stochastic gradient descent SVM (SGD-SVM), checked by using two simulation datasets. Since the classification of different ca

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Publication Date
Thu Jun 30 2022
Journal Name
Iraqi Journal Of Laser
PDF Temporal Pulse Compression Using Double Cladding Polarization Maintaining Fiber Nested Mach- Zehnder Interferometer
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Abstract: Narrow laser pulses have been essential sources in optical communication system. High data rate optical communication network system demands compressed laser source with unique optical property. In this work using pulsed duration (9) ns, peak power 1.2297mW, full width half maximum (FWHM) 286 pm, and wavelength center 1546.7 nm as compression laser source. Mach Zehnder interferometer (MZI) is built by considering two ways. First, polarization maintaining fiber (PMF) with 10 cm length is used to connect between laser source and fiber brag grating analysis (FBGA). Second, Nested Mach Zehnder interferometer (NMZI) was designed by using three PMFs with 10 cm length. These three Fibers are splicing to sing

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
تقويم قانون الخدمة الجامعية رقم 23 لسنة 2008 وأثره في تقليل مظاهر الفساد الإداري والمالي: دراسة تحليلية قدية لنصوص القانون وتطبيقاته
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This research includes an analytical and critique study for the version of the University Service Law No.23 for the year 2008, containing all its aspects and failure whether in its legislation or its applications.

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Publication Date
Mon Mar 23 2020
Journal Name
Journal Of Engineering
Experimental and Numerical Investigation on the Performance of Straight-Bladed Vertical Axis Wind Turbine by Adding Cavities to it Structure
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As the prices of the fuel and power had fluctuated many times in the last decade and new policies appeared and signed by most of the world countries to eliminate global warming and environmental impact on the earth surface and humanity exciting, an urgent need appeared to develop the renewable energy harnessing technologies on the short-term and long-term and one of these promising technologies are the vertical axis wind turbines, and mostly the combined types. The purpose of the present work is to combine a cavity type Savonius with straight bladed Darrieus to eliminate the poor self-starting ability for Darrieus type and low performance for Savonius type and for this purpose, a three-bladed Darrieus type with symmetric

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The Study of properties structure and some optical properties forcopper Oxid (CuO) Thin film prepared by thermal evaporation in Vacume
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in this paper copper oxide (cuO thin films were prepared by the method of vacum thermal evaporation a pressure.

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Publication Date
Wed Mar 01 2023
Journal Name
Chalcogenide Letters
Preparation and analysis of Ag2Se1-xTe x thin film structure on the physical properties at various temperatures by thermal evaporation
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Silver selenide telluride Semiconducting (Ag2Se0.8Te0.2) thin films were by thermal evaporation at RT with thickness350 nm at annealing temperatures (300, 348, 398, and 448) °K for 1 hour on glass substrates .using X-ray diffraction, the structural characteristics were calculated as a function of annealing temperatures with no preferential orientation along any plane. Atomic force microscopy (AFM) and X-ray techniques are used to analyze the Ag2SeTe thin films' physical makeup and properties. AFM techniques were used to analyze the surface morphology of the Ag2SeTe films, and the results showed that the values for average diameter, surface roughness, and grain size mutation increased with annealing temperature (116.36-171.02) nm The transm

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Publication Date
Wed May 03 2023
Journal Name
Chalcogenide Letters
Preparation and analysis of Ag2Se1-xTe x thin film structure on the physical properties at various temperatures by thermal evaporation
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Silver selenide telluride Semiconducting (Ag2Se0.8Te0.2) thin films were by thermal evaporation at RT with thickness350 nm at annealing temperatures (300, 348, 398, and 448) °K for 1 hour on glass substrates .using X-ray diffraction, the structural characteristics were calculated as a function of annealing temperatures with no preferential orientation along any plane. Atomic force microscopy (AFM) and X-ray techniques are used to analyze the Ag2SeTe thin films' physical makeup and properties. AFM techniques were used to analyze the surface morphology of the Ag2SeTe films, and the results showed that the values for average diameter, surface roughness, and grain size mutation increased with annealing temperature (116.36-171.02) nm The transm

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Publication Date
Mon Dec 02 2013
Journal Name
Al-nahrain Journal Of Science
Effect of Magnetized Water on Histological Structure of Heart, Lung and Spleen of Albino Rats
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The aim of the study was to investigate the effect of magnetized water on the histological structure of heart, lung and spleen. For this purpose, twenty five albino rats were divided into five equal groups, the first group was considered as control group. The other groups were given magnetized water with intensity of 250, 750, 1000, 1500 gause every day for 30 days. Then the animals were sacrificed and the histological change on heart, lung and spleen was studied. Histopathology of heart in rats treated with magnetic water with intensity of 250, 750, 1000, 1500 gause showed no clear pathological lesion. Lung section of rats treated with 250 gause of magnetic water showed no pathological lesion, while lung section belongs to rats group given

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
اثر برنامج تعليمي – تعلمي وفقاً لمفاهيم الطاقة المتجددة والنانوتكنولوجي على التنور التكنولوجي عند طلبة قسم الكيمياء
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The research aims to build an educational program - learning, according to the concepts of renewable energy and nanotechnology And knowledge of its impact on the technological enlightenment when the third phase students in the Department of Chemistry, and to verify the goal and put the researcher null hypothesis the following: No Statistically significant difference at the level (0.05) between the average scores of the experimental group students who are studying material nanotechnology and renewable energy program Altalima- learning and the average score for the control group of students who are studying the same article the usual way in technological enlightenment. The search was limited to the third row in the Department of Chemistry,

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Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
The Concept of Value in De Saussair Linguistics and their Extension in the Book (Arabic Language, Its Meaning and Structure) by Tammam Hassan
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This research was distributed into two sections, the first section was concerned with the concept of value for De Saussair and its methodological impact on his linguistic structural conceptions with respect of the distinction between synchronism and diachronism, the value role of linking function between the sounds and the though, the basing of his theoretical conception on the language being a form and not a material according to this principle and the value impact on the demonstration that the linguistic element acquires its functional importance from the relations inside the language system. It also stopped at the methodological impact of value on defining the analytical linguistic unit and the value role in semantics through the prin

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