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Directive and Steerable Radiation Pattern using SASPA Array

This work examines the ability of a special type of smart antenna array known as Switched Active Switched Parasitic Antenna (SASPA) to produce a directive and electronically steerable radiation pattern. The SASPA array consists of antenna elements that are switchable between active and parasitic states by using P-Intrinsic-N (PIN) diodes. The active element is the element that is supplied by the radio frequency while short-circuiting the terminals of an element in the array results in a parasitic element. Due to the strong mutual coupling between the elements, a directional radiation pattern with high gain and a small beamwidth can be produced with only one active element operating at a time. By changing the parasitic state to the active state sequentially for all elements, the directed radiation pattern can be easily rotated. The antenna array structure used in this work is the uniform circular array (UCA) to achieve symmetrical radiation patterns and full coverage of the entire azimuth plane. Also, a novel method for reducing the mutual coupling effect in SASPA arrays is proposed in this work. By using this method, some parameters of the generated SASPA’s radiation pattern can be controlled. The simulated results obtained from this work depict that an N-element SASPA-UCA produces N-symmetrical, switchable, and steerable radiation patterns with high gain, small beamwidth, and a high Front-to-Back (F/B) ratio. Also, the results show that further improvements in these parameters can be achieved by increasing the number of elements in the array. Additional simulations demonstrate that by including decaying function weight in each element's circuitry, the mutual coupling between the components of the SASPA-UCA array can be minimized. The aforementioned parameters can then be efficiently modified using this mutual coupling reduction.

 

 

 

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Publication Date
Mon May 14 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Investigation of the Structural, Optical and Electrical Properties of AgInSe2 Thin Films

  The Silver1Indium1Selenide (AgInSe2) (AIS) thin1films of (3001±20) nm thickness  have been1prepared2from the compound alloys2using thermal evaporation2 technique onto the glass2substrate at room temperature, with a deposition rate2(3±0.1) nm2sec-1.

The2structural, optical and electrical3properties have been studied3at different annealing3temperatures (Ta=450, 550 and 650) K.

The amount3or (concentration) of the elements3(Ag, In, Se) in the  prepared alloy3was verified using  an

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Water security in Basra Study economic reality and prospects for future water

It  can be said that the Security of water  in  Basra from the visual task vital strategic issues of concern to the attention of researchers in various attributions and those interested in water, environmental, economic, social, cultural and political affairs ... etc. This view of the great importance of the issue of water in the occupied Basra, which is characterized by parochialism and scarcity, When looking at the sources of our daily lives and in our reality today. We find that millions of people living on the two main exporters Tabaaan oil and water. And depleted oil wealth However Manfred him the most attention because we entered it surpasses all other sources of income, but is not it a littl

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Publication Date
Mon May 20 2019
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Histomorphometrical Study of Placental from Male and Female Neonates of Diabetic Women

      Objective: To investigate occur the histomatrical alternations in placental terminal villi and their vessels of Iraqi diabetes (gestational diabetes and overt diabetes) and normal pregnancies were born male and female neonates. Methods: The hitometrical study of male and female terminal villi of 68 placentae in maternal diabetes mellitus (34 gestational diabetes, 34 overt diabetes (17 DM type 1 and 17 DM type 2) and 34 normal placentae. These placentae obtained from Department of Obstetrics and Gynaecology in three hospitals in Baghdad city. Results: The study showed that there is a statistically significant with higher diameter in central and peripheral sections of the terminal villi and their vessels in m

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Curing of Maleimidyl Phenol-Formaldehyde Resins Via Esterification and Free Radical Polymerization

Three phenol-formaldehyde resins having pendant maleimides were prepared by poly condensation of N-(hydroxyphenyl) maleimides with formaldehyde under conditions similar to those in Novolac preparation. The prepared resins were modified by two methods, the first one includes esterification of phenolic hydroxyl groups in the prepared resins via their treatment with benzoyl, acryloyl, methacryloyl and cinnamoyl chlorides respectively in the presence of triethylamine, while the second modification includes free radical polymerization of vinylic bonds in the prepared resins to produce cross-linked thermally stable polymers.

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Publication Date
Wed Oct 25 2023
Journal Name
College Of Islamic Sciences
The good and bad words in Surah Ibrahim, peace be upon him

In the name of God, the Most Gracious, the Most Merciful

Praise be to God who revived Balu. And the good word brought hard hearts after removing from them what had almost killed them of ignorance, injustice, hatred, hostility, estrangement, and irritation... So God replaced for them what was best with what was best in terms of knowledge and fairness, and what was corrupt, love, and altruism. So the example of a believer and a good word is like a tree with good roots and branches. Then I pray and greet the one who watered it from the pure and inexhaustible spring of Islam, our Master Muhammad, so that the valleys flowed in their capacity, and the crops grew, then they became thicker and became even, and their good fruits in behavi

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Publication Date
Fri Jan 26 2024
Journal Name
Iraqi Journal Of Science
Distribution of Methicillin Resistant Staphylococcus aureus in Iraqi patients and Healthcare Workers

One hundred and six S. aureus were isolated from 250 Nasal swabs of
Healthcare workers and patients at Al- Kadhamia teaching Hospital and Al-
Numan hospital, Baghdad, Iraq. The study was undertaken over a period of
ten months between August 2011 and June 2012. S. aureus isolates were
diagnosed based on phenotypic traits and biochemical tests. Antibiotics
sensitivity to 11 antibiotics, revealed that S.aureus is totally resistant to
Pencillin G (100%), highly resistant to Cefoxitin (alternative to Methicillin)
(94.3%) While there are varied resistance percentage for the rest of
antibiotics: Erythromycin (37.7%), Tetracycline (34.9%), Gentamicin
(29.3%), Trimethoprim/sulfamethoxazole (50%), Ciprofloxacin (29.2%),<

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Publication Date
Sun Jun 30 2013
Journal Name
College Of Islamic Sciences
 Attribution to the verb between the grammatical rule and the linguistic reality

The research discusses the issue of attribution to the verb, because the Arab scholars are unanimous in preventing attribution of the verb, because it is always informed of it, and does not inform about it, but this consensus violates the linguistic use. The research discusses this matter.

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Publication Date
Sun May 07 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Study of Electric Quadrupole Transition (E2) in 56Ba and 62Sm Nuclei

Transition strengths ↓
2
. u . w
2) M(E for gamma transition from first excited 21
+
states to the
ground states that produced by pure electric quadrupole emission in even –even isotopes of
56Ba and 62Sm have been studied through half- lives time for 21
+
excited states with the
intensities of γ0- transitions measurements and calculated as a function of neutron number
(N). The results thus obtained have shown that; the nuclides with magic neutron number such
as 56Ba
138
and 62Sm
144
have minimum value for ↓
2
. u . w
2) M(E .

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Publication Date
Sun May 07 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Preparation of Fine Hydroxyapatite (HA) Powder And Its Characterization As Ceramic Biomaterial

Biomimatic basic calcium phosphate ,known as Hydroxy apatite(HA), was
synthesised using calcium acetate and disodium phosphate dilute hot (boiling) solution of
both salts were added slowly to each other. A colloidal suspension formed was aged for few
days, then boiled for one hour to induced setting and coagulation of preapatite, and left to cool
until they reached room temperature.
The precipitate was filtered and washed with distilled water, then ethanol and dried.
The dried sample was calcined at 1100
o
C.The obtained solid lumps were then crushed
reground fine powder and analyzed for calcium to phosphorous ratio. X-ray analysis was
carried out to examine the solid sample. Chemical analysis for phos

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Publication Date
Wed Mar 20 2019
Journal Name
Journal Of Legal Sciences
Regulation of Contracts for The Representation of Professional Players (Concept and Effects)

Regulation of contracts for the representation of professional players has great theoretical and practical importance; The FIFA has issued a new regulation to deal with football intermediaries instead of the previously exist provision of the former players' agents. The FIFA also committed the national associations to use these new regulations through issuing new national provisions. Regarding the international and national regulations, we address the meaning of the football intermediaries, the characteristics of the contracts concluded by such intermediaries and its legal provisions, the rights of the football intermediaries, and the obligations incumbent on them.

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