A method for the use of ellipticities and spot diameters for the measurement of aberrations in wide-field telescopes

2014 ◽  
Vol 3 (3) ◽  
Author(s):  
Lothar Noethe ◽  
Pietro Schipani ◽  
Ronald Holzlöhner ◽  
Andrew Rakich
Keyword(s):  
Field Dependence ◽  
Gravitational Lensing ◽  
Closed Loop ◽  
Field Survey ◽  
Closed Loop Control ◽  
Zernike Polynomials ◽  
Wide Field ◽  
Loop Control ◽  
Wavefront Aberrations ◽  
Telescope Optics

AbstractIn wide-field survey telescopes, the patterns of spot sizes and ellipticities can be used to determine wavefront aberrations generated by the telescope. The calculation of spot sizes and ellipticities generated by telescope aberrations is most conveniently done if the aberrations are expressed in terms of Zernike-type polynomials whose derivatives are orthonormal. The field dependence of the spot sizes and ellipticities generated by the telescope can conveniently be expressed by low-order Zernike polynomials. Because the exposure times in astronomical survey work are typically rather short, this information may be used for a quasi-closed loop control of the telescope optics. The ability to accurately subtract ellipticities generated by telescope errors could also be useful for observations such as gravitational lensing surveys.

The Impact of Visual Feedback Type on the Mastery of Visuo-Motor Transformations

2012 ◽  
Vol 220 (1) ◽  
pp. 3-9 ◽  
Author(s):  
Sandra Sülzenbrück
Keyword(s):  
Empirical Research ◽  
Visual Feedback ◽  
Closed Loop ◽  
Motor Planning ◽  
Visual Input ◽  
Closed Loop Control ◽  
Loop Control ◽  
Feedback Type ◽  
Effective Use ◽  
The Impact

For the effective use of modern tools, the inherent visuo-motor transformation needs to be mastered. The successful adjustment to and learning of these transformations crucially depends on practice conditions, particularly on the type of visual feedback during practice. Here, a review about empirical research exploring the influence of continuous and terminal visual feedback during practice on the mastery of visuo-motor transformations is provided. Two studies investigating the impact of the type of visual feedback on either direction-dependent visuo-motor gains or the complex visuo-motor transformation of a virtual two-sided lever are presented in more detail. The findings of these studies indicate that the continuous availability of visual feedback supports performance when closed-loop control is possible, but impairs performance when visual input is no longer available. Different approaches to explain these performance differences due to the type of visual feedback during practice are considered. For example, these differences could reflect a process of re-optimization of motor planning in a novel environment or represent effects of the specificity of practice. Furthermore, differences in the allocation of attention during movements with terminal and continuous visual feedback could account for the observed differences.

118-LB: Glucose Variability throughout the Menstrual Cycle on Closed-Loop Control in Type 1 DM

Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 118-LB
Author(s):  
CAROL J. LEVY ◽  
GRENYE OMALLEY ◽  
SUE A. BROWN ◽  
DAN RAGHINARU ◽  
YOGISH C. KUDVA ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Closed Loop ◽  
Glucose Variability ◽  
Closed Loop Control ◽  
Loop Control ◽  
Type 1 Dm

101-LB: Eighteen-Month Use of Closed-Loop Control (CLC): A Randomized, Controlled Trial

Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 101-LB
Author(s):  
SUE A. BROWN ◽  
DAN RAGHINARU ◽  
BRUCE A. BUCKINGHAM ◽  
YOGISH C. KUDVA ◽  
LORI M. LAFFEL ◽  
...  
Keyword(s):  
Randomized Controlled Trial ◽  
Closed Loop ◽  
Controlled Trial ◽  
Closed Loop Control ◽  
Loop Control ◽  
Randomized Controlled
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