Power loss due to beam splitter cascade in the simultaneous sampling of a volume speckle field for phase retrieval

2008 ◽  
Author(s):  
Anne Margarette S. Maallo ◽  
Percival F. Almoro
2010 ◽  
Author(s):  
Mingguang Shan ◽  
Pei Zhi ◽  
Zhi Zhong ◽  
Bo Zhu

2007 ◽  
Vol 32 (7) ◽  
pp. 733 ◽  
Author(s):  
P. Almoro ◽  
G. Pedrini ◽  
W. Osten

2012 ◽  
Author(s):  
Percival F. Almoro ◽  
Laura Waller ◽  
Mostafa Agour ◽  
Claas Falldorf ◽  
Giancarlo Pedrini ◽  
...  

2012 ◽  
Vol 37 (11) ◽  
pp. 2088 ◽  
Author(s):  
Percival F. Almoro ◽  
Laura Waller ◽  
Mostafa Agour ◽  
Claas Falldorf ◽  
Giancarlo Pedrini ◽  
...  

2009 ◽  
Vol 34 (10) ◽  
pp. 1522 ◽  
Author(s):  
Arun Anand ◽  
Vani K Chhaniwal ◽  
Percival Almoro ◽  
Giancarlo Pedrini ◽  
Wolfgang Osten

Author(s):  
W. Coene ◽  
A. Thust ◽  
M. Op de Beeck ◽  
D. Van Dyck

Compared to conventional electron sources, the use of a highly coherent field-emission gun (FEG) in TEM improves the information resolution considerably. A direct interpretation of this extra information, however, is hampered since amplitude and phase of the electron wave are scrambled in a complicated way upon transfer from the specimen exit plane through the objective lens towards the image plane. In order to make the additional high-resolution information interpretable, a phase retrieval procedure is applied, which yields the aberration-corrected electron wave from a focal series of HRTEM images (Coene et al, 1992).Kirkland (1984) tackled non-linear image reconstruction using a recursive least-squares formalism in which the electron wave is modified stepwise towards the solution which optimally matches the contrast features in the experimental through-focus series. The original algorithm suffers from two major drawbacks : first, the result depends strongly on the quality of the initial guess of the first step, second, the processing time is impractically high.


Author(s):  
Peter P. J. L. Verkoeijen ◽  
Remy M. J. P. Rikers ◽  
Henk G. Schmidt

Abstract. The spacing effect refers to the finding that memory for repeated items improves when the interrepetition interval increases. To explain the spacing effect in free-recall tasks, a two-factor model has been put forward that combines mechanisms of contextual variability and study-phase retrieval (e.g., Raaijmakers, 2003 ; Verkoeijen, Rikers, & Schmidt, 2004 ). An important, yet untested, implication of this model is that free recall of repetitions should follow an inverted u-shaped relationship with interrepetition spacing. To demonstrate the suggested relationship an experiment was conducted. Participants studied a word list, consisting of items repeated at different interrepetition intervals, either under incidental or under intentional learning instructions. Subsequently, participants received a free-recall test. The results revealed an inverted u-shaped relationship between free recall and interrepetition spacing in both the incidental-learning condition and the intentional-learning condition. Moreover, for intentionally learned repetitions, the maximum free-recall performance was located at a longer interrepetition interval than for incidentally learned repetitions. These findings are interpreted in terms of the two-factor model of spacing effects in free-recall tasks.


2007 ◽  
Author(s):  
Peter M. Wessels ◽  
Jonathan Schnader ◽  
Allison Smith ◽  
Christopher Thomas ◽  
Haley Titus

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