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Zernike Polynomiales· for Opticl Ssytew. With Borizantal Recta_nguJar Aperture
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For  small   aberrations,  the  Â·suehl'  ratio of  an . im i'ng syStem

  • depends on trne aberration v·ariance. Its· aberration fu.nct1on ·is e:qJanded in terms 9f-l nike polynomials. which are_ oirrh6goilal over a circular apeltitte. Their advane Uejn the    f;:l t tbat they call be icl.eritified. witl·c1a:s.sh::aj. abe,ttati{)ns 'balanced to jield  minimum varia,.o_q,and

thuS maximum St:rehl  t"a;tio. [n r«enr pap-er, we derived Cl<lse4 .fonn or

Zmike   polyhotnials  that  ate  orthonormal  over "- horizontal rect'angul'ar pupil'. (p.anil.lel to· the >Htxi.es) with ar'€a equal 1t.  Ustng the circle pO:lynomials as the · basis functions. f(;)r  th:ehl- onb.ogonalization

p_ver  such   pupil,    we: ;derive   closed-foim  polyr.wmials   that   are ortbonormaJ  over   rectangular  pupil  by us ng,  Gram-sl1m.it  method These· polynomials,  we unique in that they  rue_ not  <:>nly  orthogonal

acrossuch- pupils,. but aJ:so -re.present balanced -classicl aberrations,

just as tbe Zemike ·circlpolyiiornials are unique in- these respects but

also repr sent balanced dasskal  aberration$.

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Publication Date
Tue Jan 01 2013
Journal Name
Iraqi Journal Of Physics
Describing the Wavefront Aberrations of the Hexagonal Aperture Using Modified Zernike Polynomials
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n Segmented Optical Telescope (NGST) with hexagonal segment of spherical primary mirror can provide a 3 arc minutes field of view. Extremely Large Telescopes (ELT) in the 100m dimension would have such unprecedented scientific effectiveness that their construction would constitute a milestone comparable to that of the invention of the telescope itself and provide a truly revolutionary insight into the universe. The scientific case and the conceptual feasibility of giant filled aperture telescopes was our interested. Investigating the requirements of these imply for possible technical options in the case of a 100m telescope. For this telescope the considerable interest is the correction of the optical aberrations for the coming wavefront, th

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Describing the Wavefront Aberrations of the Hexagonal Aperture Using Modified Zernike Polynomials
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The concept of the optical telescope is the primary mirror design, the Next Generation Segmented Optical Telescope (NGST) with hexagonal segment of spherical primary mirror can provide a 3 arc minutes field of view. Extremely Large Telescopes (ELT) in the 100m dimension would have such unprecedented scientific effectiveness that their construction would constitute a milestone comparable to that of the invention of the telescope itself and provide a truly revolutionary insight into the universe. The scientific case and the conceptual feasibility of giant filled aperture telescopes was our interested. Investigating the requirements of these imply for possible technical options in the case of a 100m telescope. For this telescope the conside

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Publication Date
Fri Apr 02 2021
Journal Name
New Trends In Information And Communications Technology Applications: 4th International Conference, Ntict 2020, Baghdad, Iraq, June 15, 2020, Proceedings 4
Iris recognition using localized Zernike features with partial iris pattern
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Publication Date
Sat Jan 01 2005
Journal Name
Iraqi Journal Of Science
Comparison between Zernike moment and central moments for matching problem
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Moment invariants have wide applications in image recognition since they were proposed.

Publication Date
Thu Jun 20 2019
Journal Name
Baghdad Science Journal
A Comparative Analysis of the Zernike Moments for Single Object Retrieval
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Zernike Moments has been popularly used in many shape-based image retrieval studies due to its powerful shape representation. However its strength and weaknesses have not been clearly highlighted in the previous studies. Thus, its powerful shape representation could not be fully utilized. In this paper, a method to fully capture the shape representation properties of Zernike Moments is implemented and tested on a single object for binary and grey level images. The proposed method works by determining the boundary of the shape object and then resizing the object shape to the boundary of the image. Three case studies were made. Case 1 is the Zernike Moments implementation on the original shape object image. In Case 2, the centroid of the s

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Publication Date
Thu May 28 2020
Journal Name
Iraqi Journal Of Science
Synthetic Aperture Radar Image Classification: a Survey: Survey
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In this review paper, several studies and researches were surveyed for assisting future researchers to identify available techniques in the field of classification of Synthetic Aperture Radar (SAR) images. SAR images are becoming increasingly important in a variety of remote sensing applications due to the ability of SAR sensors to operate in all types of weather conditions, including day and night remote sensing for long ranges and coverage areas. Its properties of vast planning, search, rescue, mine detection, and target identification make it very attractive for surveillance and observation missions of Earth resources.  With the increasing popularity and availability of these images, the need for machines has emerged to enhance t

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Publication Date
Wed May 31 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Studying of Optical System Includes Elliptical Aperture Point Spread Function
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In this work, optical system with elliptical aperture using point spread function was studied. This is due to its comparison with an optical system with a circular aperture. The present work deals with the theoretical study of intensity distribution within the image. In this work, a special formula was derived which is called the point spread function (PSF) by using a pupil function technique. The work deals with the limited optical system diffraction only (ideal system), and the system with focal shift. Also a graphic relation was founded between eccentricity and the best of focal depth given to at least (80%) of intensity.

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Publication Date
Sun Jun 03 2012
Journal Name
Baghdad Science Journal
Study of effect of non-central obscuration to obscured circular aperture on third order spherical aberration
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In this research we have been studied the 3rd order spherical aberration for an optical system consisted of obscured circular aperture with non central circular obscuration through the calculation of point spread function (P.S.F) in presence of the obscuration in the center and comparing the obtained results with that results of moving obscuration far away from the center, where the results showed significant improvement for(P.S.F) value. The study was done of different obscurities ratios in addition to the different 3rd order spherical aberration values (W40=0.25 ,0.5 ,0.75 ,1 ).

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Publication Date
Tue Feb 02 2021
Journal Name
Journal Of Engineering Science And Technology
INVESTIGATING THE EFFECT OF INLET APERTURE AND BAFFLE POSITION IN IMPROVING THE EFFICIENCY OF PRIMARY SETTLING TANKS
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Publication Date
Fri Sep 09 2022
Journal Name
Revista Mexicana De Oftalmología (english Edition)
Posterior subtenon triamcinolone acetonide combined with phacoemulsification for patients with diabetic maculopathy
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