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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
Mon Dec 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
أتجاهات مقارنة في تنظيم الادارة المحلية دراسة تحليلية
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ليست الادارة المحلية أو نظام الحكم المحلي ابتكاراُ حديثاً للانسان، بل أنه لازم البشرية منذ أقدم العصور وحتى الآن، إذ الملاجظ أن القرى الصغيرة نشأت قبل أن تنشئ الدولة أو قيل أن يتبلور مفهوم الدولة في الوقت الحاضر وكانت القرى والمدن تجتمع بين حين وأخر- اجتماع أفرادها- لادارة شؤونهم وحل مشاكلهم، وكان هذا خير دليل لتطبيق مفهوم الديمقراطية المباشرة بين أفراد المجتمع الواحد، ولذلك فإن الحك

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Publication Date
Fri Jun 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
مكانية استخدام السوق المالية في التنبؤ بالدورات الاقتصادية
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مكانية استخدام السوق المالية في التنبؤ بالدورات الاقتصادية

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Publication Date
Thu Mar 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
فلسفة نوعية حياة العمل في منظمات الألفية الثالثة
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المقدمة

تجدد الاهتمام بموضوع نوعية حياة العمل (Quality of life) الذي يرمز له اختصارا (QWL)، في السنوات الأخيرة الماضية، وبمطلع الألفية الثالثة على وجه التحديد، من قبل الباحثين الأكاديميين والمهتمين الممارسين في منظمات الأعمال، وذلك بوصفهم إليه بأنه أهم مصادر الرضا للعاملين، والعنصر المميز لبيئة عمل منظمة ما عن غيرها. وهنا، قد برزت الاضطلاع بالمسؤولية الأخ

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Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
المقالات البارزة في الفكر الاداري والاقتصادي والمحاسبي والاحصائي
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انطلاقاً من ضرورات التجديد والتطوير لمجلتنا العزيزة، ستجرى اضافات عليها بين الحين والآخر، قد تتناول شكلياتها و/ او محتوياتها. والبداية ستكون بترجمة المقالات والبحوث التي تقع في اختصاصها من المجلات الاجنبية المرموقة عالمياً، فإختارت هيئة التحرير المقالات الخمسة التي سيرد ذكرها لاحقاً للقيام بترجمتها بأسلوب علمي يعطي للتصرف والاضافات حدوداً لتصبح مقبولة وسهلة على القراء. فالمهمة هذه وان كانت صعبة وتت

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Effect of Nickel Substitution On Structural and Electrical Properties of Hg<sub>0.5</sub>Pb<sub>0.5</sub>Ba<sub>2</sub>Ca<sub>2</sub>Cu<sub>3-y</sub>Ni<sub>y</sub>O<sub>8+δ</sub> Superconductor Composite
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Abstract<p>six specimens of the Hg<sub>0.5</sub>Pb<sub>0.5</sub>Ba<sub>2</sub>Ca<sub>2</sub>Cu<sub>3-y</sub> <italic>Ni<sub>y</sub> </italic>O<sub>8+δ</sub> (y=0.2,0.4,0.6,0.8,1.0) superconducting compound were prepared by solid state reaction method, with sintering temperature equal to 1123K for 24 hours. The electrical resistivity was examined by the four probe technique, It was found that all the specimens have metallic behavior and increasing the critical temperature with increasing nickel concentration. The optimum critical temperature T<sub>c</sub> was found equal </p> ... Show More
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Publication Date
Sat Mar 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
تقويم واقع نشاط التدريب وتوثيقه في إطار تطبيقات المواصفة الإرشادية الدولية (10015 ISO) دراسة حالة في وزارة البلديات والأشغال العامة
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This research has taken to the knowledge of the scope of  applying the international specification of (ISO 10015) which is regarded to training by the Iraqi ministry of municipalities and public works ,in order to determine its training quality .By using the checklist made based upon the items of the specification ,after translating the English copy into Arabic ,which takes the indications of training depending on qualitative bases. The results of the analysis emphasized that occurred total average by comparison the evaluation of the training activity in the mentioned ministry with the international specification in all of its main items, which was (%55) ,and totally documented ,which finally refer to the existence of great

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Publication Date
Sun Jun 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
اختبار أساليب تحديد حجم الدفعة المستخدمة في نظام MRP II* دراسة حالة في الشركة العامة لصناعة البطاريات معمل بابل /1
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      MRP is a system intended for the batch manufacturing of discrete parts including assemblies and subassemblies that should be stocked to support future manufacturing needs.  Due to the useful information provided by MRP it has evolved into a Manufacturing Resources Planning, MRP II, a system that ties the basic MRP system to the other functional areas of the company such as marketing, finance, purchasing, etc.  The objective of this research, which was conducted at the State Company for Batteries Manufacturing, is to test the performance of some popular lot-sizing techniques used within MRP II framework. It is hypothesized that the technique which minimizes the total inventory costs does no

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Publication Date
Wed Dec 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
تقنيات شبكة المعلومات ودورها في إنجاز عمليات الشراء الالكتروني والتسويق الالكتروني* دراسة حالة في شركة بغداد للمشروبات الغازية- المساهمة المختلطة
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Information Technology has become one of the Most Prominent tools in the Era of Technology and Telecommunication of our Digital World. For that Reasons most Organizations had taken the tools Adapted to their Present and Future Directions and for the Improvement for it's Operations and Workability in Internal or External Enviroment. Consequently the Points of Strength Beats the Weakness and as Result of Increase Opportunities and Decrease the Threats Facing these Organizations. This Search has been made to test the Existence or not Existence role of the Information Network Technologies that Include {Internet and Extranet} in Application of Information Technology t

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Publication Date
Mon Dec 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
استخدام البرمجة الديناميكية في حل انموذج المعاينة الدورية الثابته لمشكلة الخزين مع تطبيق عملي في شركة الاقصى التجارية لاستيراد المولدات
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The purpose of this paper is use the Dynamic Programming to solve a deterministic periodic review model for inventory problem and then to find the optimal policies that the company must uses in the purchase or production  (in the practical application example the Al Aksa company purchase the generators from out side country).

 

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Publication Date
Sun Jul 14 2024
Journal Name
مجلة دراسات وبحوث التربية الرياضية
Construction and Validation of a Cognitive Engagement Scale and Its Relationship with Ball Movement Sequence Performance in Rhythmic Gymnastics
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The research aims to: build and record a measure of cognitive participation among second-year female students at the College of Physical Education and Sports Sciences, University of Baghdad. The researchers used the descriptive approach in the survey style for the research sample. The sample was selected from female students and divided into: (10) female students for the survey sample, and (80) female students for the construction and codification sample. The data were statistically analyzed by the researchers using SPSS, the T-test for independent and correlated samples, Pearson's simple correlation coefficient, Cronbach's alpha, Chi-square, and Spearman-Brown. They were recruited for the samples. The study concluded that constr

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