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You searched for subject:( Spectropolarimetric). Showing records 1 – 3 of 3 total matches.

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University of Delaware

1. Fu, Chen. Compressive polar spectral and polarization imaging.

Degree: PhD, University of Delaware, Department of Electrical and Computer Engineering, 2018, University of Delaware

Conventional digital imaging captures the desired image information directly on an imaging sensor. When high dimensional imaging capability is required such as spectral imaging and spectropolarimetric imaging, inecient sampling strategies are usually involved, such as scanning and division of the focal plane array, resulting in either poor real-time imaging capability or sensor resolution reduction. Compressive sensing solves these problems via sampling of the high-dimensional image cubes below the Nyquist sampling rate, and recovering the image signal with sparsity constraints. In this dissertation, a newly proposed compressive spectral imaging and a compressive spectropolarimetric imaging system are described. In particular, a novel polar-shaped pixelated coding mask is proposed, optimized and implemented in spinning imaging systems. Multi-snapshots are achieved through the coding mask rotation. By combin- ing with a circular variable lter and a low-resolution monochrome sensor array, super- resolution in both spatial and spectral dimensions is attained. Both the geometry and the pattern of binary polar coded aperture are further optimized. A continuous imager rotation model is developed and simulated to resolve the rotation blur. Finally, the imaging system is tested with experimental measurements and reconstructions. On the other hand, a compressive spectropolarimetric imager is developed based on a micro- polarizer array, aiming at obtaining spectral linear Stokes images. Simulation shows a blue-noise pattern of micro-polarizer distribution highly improves the polarization reconstruction quality. A rotating double-amici prism further enables multi-snapshots. Reconstructions of spectral Stokes images as well as the degree and angle of polarization (DoP and AoP) images are then obtained from testbed experiments. Advisors/Committee Members: Arce, Gonzalo R..

Subjects/Keywords: Applied sciences; Compressive sensing; Polar coded aperture; Compressive spectropolarimetric imager

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Fu, C. (2018). Compressive polar spectral and polarization imaging. (Doctoral Dissertation). University of Delaware. Retrieved from http://udspace.udel.edu/handle/19716/23907

Chicago Manual of Style (16th Edition):

Fu, Chen. “Compressive polar spectral and polarization imaging.” 2018. Doctoral Dissertation, University of Delaware. Accessed March 05, 2021. http://udspace.udel.edu/handle/19716/23907.

MLA Handbook (7th Edition):

Fu, Chen. “Compressive polar spectral and polarization imaging.” 2018. Web. 05 Mar 2021.

Vancouver:

Fu C. Compressive polar spectral and polarization imaging. [Internet] [Doctoral dissertation]. University of Delaware; 2018. [cited 2021 Mar 05]. Available from: http://udspace.udel.edu/handle/19716/23907.

Council of Science Editors:

Fu C. Compressive polar spectral and polarization imaging. [Doctoral Dissertation]. University of Delaware; 2018. Available from: http://udspace.udel.edu/handle/19716/23907


Universidade do Rio Grande do Norte

2. Duarte, Tharcisyo Sa e Sousa. Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria .

Degree: 2012, Universidade do Rio Grande do Norte

This study proposes an observing program focused on the investigation of the stellar magnetism and dynamo evolution in cool active solar-like stars. More mainly in the solar analogs and twins. Observations of stars of our base were carried out with two spectropolarimeter ([email protected] and [email protected]). The analyse of stars in stage different allows an understanding of the dependence of magnetic activity on basic stellar parameters such as rotation, mass, age and depth of the convection zone. This study provides measures necessary for testing dynamo theories. The 65 targets for this project are solar type stars with mass spanning from 0:9 M=Mfi 1:075 solar masses and at different evolutionary stages. Our two main science objectives were, (i) To determine how the magnetic field evolved from the ZAMS to the TO (turn off) for stars with 0:9 M=Mfi 1:075; (ii) To determine the impact of convective depth and rotation on magnetic of cool stars of solar type. The main result from this study was the characterization of the dependence of magnetic field intensity as function of age, Rossby number and the convective zone deepening. This context, the availability of ESPaDOnS and NARVAL opens an exceptional possibility to study the magnetic properties of Sun-like stars by means of spectropolarimetric observations Advisors/Committee Members: Nascimento Júnior, José Dias do (advisor), CPF:85106038472 (advisor), http://lattes.cnpq.br/5498036360601584 (advisor).

Subjects/Keywords: Magnetismo estelar; Evolução; Estrelas análogas solares; Estrelas gêmeas solares; Espectropolarimetria; Stellar magnetism; Spectropolarimetric

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Duarte, T. S. e. S. (2012). Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria . (Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/18597

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Duarte, Tharcisyo Sa e Sousa. “Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria .” 2012. Thesis, Universidade do Rio Grande do Norte. Accessed March 05, 2021. http://repositorio.ufrn.br/handle/123456789/18597.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Duarte, Tharcisyo Sa e Sousa. “Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria .” 2012. Web. 05 Mar 2021.

Vancouver:

Duarte TSeS. Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria . [Internet] [Thesis]. Universidade do Rio Grande do Norte; 2012. [cited 2021 Mar 05]. Available from: http://repositorio.ufrn.br/handle/123456789/18597.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Duarte TSeS. Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria . [Thesis]. Universidade do Rio Grande do Norte; 2012. Available from: http://repositorio.ufrn.br/handle/123456789/18597

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Universidade do Rio Grande do Norte

3. Duarte, Tharcisyo Sa e Sousa. Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria .

Degree: 2012, Universidade do Rio Grande do Norte

This study proposes an observing program focused on the investigation of the stellar magnetism and dynamo evolution in cool active solar-like stars. More mainly in the solar analogs and twins. Observations of stars of our base were carried out with two spectropolarimeter ([email protected] and [email protected]). The analyse of stars in stage different allows an understanding of the dependence of magnetic activity on basic stellar parameters such as rotation, mass, age and depth of the convection zone. This study provides measures necessary for testing dynamo theories. The 65 targets for this project are solar type stars with mass spanning from 0:9 M=Mfi 1:075 solar masses and at different evolutionary stages. Our two main science objectives were, (i) To determine how the magnetic field evolved from the ZAMS to the TO (turn off) for stars with 0:9 M=Mfi 1:075; (ii) To determine the impact of convective depth and rotation on magnetic of cool stars of solar type. The main result from this study was the characterization of the dependence of magnetic field intensity as function of age, Rossby number and the convective zone deepening. This context, the availability of ESPaDOnS and NARVAL opens an exceptional possibility to study the magnetic properties of Sun-like stars by means of spectropolarimetric observations Advisors/Committee Members: Nascimento Júnior, José Dias do (advisor), CPF:85106038472 (advisor), http://lattes.cnpq.br/5498036360601584 (advisor).

Subjects/Keywords: Magnetismo estelar; Evolução; Estrelas análogas solares; Estrelas gêmeas solares; Espectropolarimetria; Stellar magnetism; Spectropolarimetric

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Duarte, T. S. e. S. (2012). Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria . (Masters Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/18597

Chicago Manual of Style (16th Edition):

Duarte, Tharcisyo Sa e Sousa. “Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria .” 2012. Masters Thesis, Universidade do Rio Grande do Norte. Accessed March 05, 2021. http://repositorio.ufrn.br/handle/123456789/18597.

MLA Handbook (7th Edition):

Duarte, Tharcisyo Sa e Sousa. “Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria .” 2012. Web. 05 Mar 2021.

Vancouver:

Duarte TSeS. Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria . [Internet] [Masters thesis]. Universidade do Rio Grande do Norte; 2012. [cited 2021 Mar 05]. Available from: http://repositorio.ufrn.br/handle/123456789/18597.

Council of Science Editors:

Duarte TSeS. Investigando o campo magnético das estrelas análogas e gêmeas solares através da espectropolarimetria . [Masters Thesis]. Universidade do Rio Grande do Norte; 2012. Available from: http://repositorio.ufrn.br/handle/123456789/18597

.