Characterization of Photon Statistical Properties with Normalized Mandel Parameter

2008 ◽  
Vol 25 (11) ◽  
pp. 3976-3979 ◽  
Author(s):  
Zhang Xin-Zheng ◽  
Wang Zhen-Hua ◽  
Li Hui ◽  
Wu Qiang ◽  
Tang Bai-Quan ◽  
...  
2010 ◽  
Vol 17 (3) ◽  
pp. 283-285
Author(s):  
A. M. Mancho ◽  
S. Wiggins ◽  
A. Turiel ◽  
E. Hernández-García ◽  
C. López ◽  
...  

Abstract. Nonlinear phenomena are essential ingredients in many oceanic and atmospheric processes, and successful understanding of them benefits from multidisciplinary collaboration between oceanographers, meteorologists, physicists and mathematicians. The present Special Issue on "Nonlinear Processes in Oceanic and Atmospheric Flows" contains selected contributions from attendants to the workshop which, in the above spirit, was held in Castro Urdiales, Spain, in July 2008. Here we summarize the Special Issue contributions, which include papers on the characterization of ocean transport in the Lagrangian and in the Eulerian frameworks, generation and variability of jets and waves, interactions of fluid flow with plankton dynamics or heavy drops, scaling in meteorological fields, and statistical properties of El Niño Southern Oscillation.


2008 ◽  
Vol 25 (12) ◽  
pp. 2230-2244 ◽  
Author(s):  
Carlo Capsoni ◽  
Michele D’Amico ◽  
Paolo Locatelli

Abstract A large collection of radar reflectivity maps gathered from 1988 to 1992 at the Spino d’Adda experimental station, located in the Padana Valley, has been exploited to investigate the statistical properties of rain structures and their descriptors. The results of this analysis can be of interest for meteorological, hydrological, and telecommunication applications. The authors found that the isosuperficial diameter follows an exponential distribution; when the threshold of rain intensity is increased, disappearance is dominant over fragmentation; moreover, the number of “mother cells” that generate N “daughter cells” decreases exponentially with N. To give a complete but concise characterization of the geometrical, physical, and morphological properties of rain cells, a set of analytical descriptors has been introduced and statistically defined through their probability density functions and the centrality, dispersion, and excursion parameters. As a final point, comparative statistical analyses have been performed at different thresholds for every couple of descriptors introduced, which allowed the authors to highlight correlations between them.


1995 ◽  
Vol 32 (02) ◽  
pp. 548-553
Author(s):  
M. E. Ghitany ◽  
M. A. El-saidi ◽  
Z. Khalil

In this paper we establish a characterization theorem for a general class of life-testing models based on a relationship between conditional expectation and the failure rate function. As a simple application of the theorem, we characterize the gamma, Weibull, and Gompertz distributions, since they have many probabilistic and statistical properties useful in both biometry and engineering reliability.


2018 ◽  
Author(s):  
Ingo Fruend ◽  
Elee Stalker

Humans are remarkably well tuned to the statistical properties of natural images. However, quantitative characterization of processing within the domain of natural images has been difficult because most parametric manipulations of a natural image make that image appear less natural. We used generative adversarial networks (GANs) to constrain parametric manipulations to remain within an approximation of the manifold of natural images. In the first experiment, 7 observers decided which one of two synthetic perturbed images matched a synthetic unperturbed comparison image. Observers were significantly more sensitive to perturbations that were constrained to an approximate manifold of natural images than they were to perturbations applied directly in pixel space. Trial by trial errors were consistent with the idea that these perturbations disrupt configural aspects of visual structure used in image segmentation. In a second experiment, 5 observers discriminated paths along the image manifold as recovered by the GAN. Observers were remarkably good at this task, confirming that observers were tuned to fairly detailed properties of an approximate manifold of natural images. We conclude that human tuning to natural images is more general than detecting deviations from natural appearance, and that humans have, to some extent, access to detailed interrelations between natural images.


1994 ◽  
Vol 33 (34) ◽  
pp. 7838 ◽  
Author(s):  
Ivan Ohlídal ◽  
Karel Navrátil ◽  
Miloslav Ohlídal ◽  
Miloslav Druckmüller

2021 ◽  
Author(s):  
Raphaël Liégeois ◽  
B. T. Thomas Yeo ◽  
Dimitri Van De Ville

AbstractNull models are necessary for assessing whether a dataset exhibits non-trivial statistical properties. These models have recently gained interest in the neuroimaging community as means to explore dynamic properties of functional Magnetic Resonance Imaging (fMRI) time series. Interpretation of null-model testing in this context may not be straightforward because (i) null hypotheses associated to different null models are sometimes unclear and (ii) fMRI metrics might be ‘trivial’, i.e. preserved under the null hypothesis, and still be useful in neuroimaging applications. In this commentary, we review several commonly used null models of fMRI time series and discuss the interpretation of the corresponding tests. We argue that, while null-model testing allows for a better characterization of the statistical properties of fMRI time series and associated metrics, it should not be considered as a mandatory validation step to assess their relevance in neuroimaging applications.


2021 ◽  
Vol 9 (2) ◽  
pp. 5-35
Author(s):  
César Daltoé Berci ◽  
Ceslo Pascoli Bottura

Several characteristics of financial time series are of interest both from an academic point of view, which is intended to analyze the dynamics of the data and its numerical properties, as well as from investors point of view, who use this knowledge to generate profit in their financial transactions. By applying several analysis tools and using a massive computing capacity, the numerical and statistical properties of the assets that compose the IBOVESPA index were evaluated. Given the relevance and scope of the analyzed time series, the results obtained from this analysis can serve as a basis for the characterization of financial time series


1997 ◽  
Author(s):  
Stephan Bojinski ◽  
Sergei A. Shapiro ◽  
Norbert Gold ◽  
Jochen Stanullo

2019 ◽  
Vol 16 (156) ◽  
pp. 20190239 ◽  
Author(s):  
Jamie A. Booth ◽  
Verena Tinnemann ◽  
René Hensel ◽  
Eduard Arzt ◽  
Robert M. McMeeking ◽  
...  

Dry adhesives using surface microstructures inspired by climbing animals have been recognized for their potentially novel capabilities, with relevance to a range of applications including pick-and-place handling. Past work has suggested that performance may be strongly dependent on variability in the critical defect size among fibrillar sub-contacts. However, it has not been directly verified that the resulting adhesive strength distribution is well described by the statistical theory of fracture used. Using in situ contact visualization, we characterize adhesive strength on a fibril-by-fibril basis for a synthetic fibrillar adhesive. Two distinct detachment mechanisms are observed. The fundamental, design-dependent mechanism involves defect propagation from within the contact. The secondary mechanism involves defect propagation from fabrication imperfections at the perimeter. The existence of two defect populations complicates characterization of the statistical properties. This is addressed by using the mean order ranking method to isolate the fundamental mechanism. The statistical properties obtained are subsequently used within a bimodal framework, allowing description of the secondary mechanism. Implications for performance are discussed, including the improvement of strength associated with elimination of fabrication imperfections. This statistical analysis of defect-dependent detachment represents a more complete approach to the characterization of fibrillar adhesives, offering new insight for design and fabrication.


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