scholarly journals Search for Non-Gaussianities in the WMAP Data with the Scaling Index Method

2011 ◽  
Vol 2011 ◽  
pp. 1-21 ◽  
Author(s):  
G. Rossmanith ◽  
H. Modest ◽  
C. Räth ◽  
A. J. Banday ◽  
K. M. Górski ◽  
...  
Keyword(s):  
Structural Characteristics ◽  
Microwave Background ◽  
Index Method ◽  
Data Set ◽  
Local Type ◽  
Statistical Measures ◽  
Wmap Data ◽  
Statistical Isotropy ◽  
Scaling Index ◽  
Scaling Index Method

In the recent years, non-Gaussianity and statistical isotropy of the Cosmic Microwave Background (CMB) was investigated with various statistical measures, first and foremost by means of the measurements of the WMAP satellite. In this paper, we focus on the analyses that were accomplished with a measure of local type, the so-calledScaling Index Method(SIM). The SIM is able to detect structural characteristics of a given data set and has proven to be highly valuable in CMB analysis. It was used for comparing the data set with simulations as well as surrogates, which are full-sky maps generated by randomisation of previously selected features of the original map. During these investigations, strong evidence for non-Gaussianities as well as asymmetries and local features could be detected. In combination with the surrogates approach, the SIM detected the highest significances for non-Gaussianity to date.

Scaling-index method as an image processing tool in scanning-probe microscopy

2001 ◽  
Vol 86 (1-2) ◽  
pp. 241-246 ◽  
Author(s):  
F Jamitzky ◽  
R.W Stark ◽  
W Bunk ◽  
S Thalhammer ◽  
C Räth ◽  
...  
Keyword(s):  
Image Processing ◽  
Scanning Probe Microscopy ◽  
Scanning Probe ◽  
Index Method ◽  
Probe Microscopy ◽  
Scaling Index ◽  
Scaling Index Method

Scaling index method: a novel nonlinear technique for the analysis of high-resolution MRI of human bones

2003 ◽  
Author(s):  
Roberto A. Monetti ◽  
Holger Bohm ◽  
Dirk Muller ◽  
David Newitt ◽  
Sharmila Majumdar ◽  
...  
Keyword(s):  
High Resolution ◽  
Index Method ◽  
Human Bones ◽  
High Resolution Mri ◽  
Nonlinear Technique ◽  
Scaling Index ◽  
Scaling Index Method

scholarly journals Method for evaluation of the cleanliness grade of coal resources in the Huainan Coalfield, Anhui, China: a case study

2021 ◽  
Author(s):  
Guangqing Hu ◽  
Guijian Liu ◽  
Dun Wu ◽  
Wenyong Zhang ◽  
Biao Fu
Keyword(s):  
Trace Elements ◽  
Coal Seam ◽  
Regional Distribution ◽  
Large Data ◽  
Index Method ◽  
Data Set ◽  
Poor Grade ◽  
Huainan Coalfield ◽  
Coal Grade ◽  
Grade Iii

AbstractBased on analysis of a large data set and supplementary sampling and analysis for hazardous trace elements in coal samples from the Huainan Coalfield, a generalized contrast-weighted scale index method was used to establish a model to evaluate the grade of coal cleanliness and its regional distribution in the main coal seam (No. 13-1) The results showed that: (1) The contents of Cr, Mn and Ni in the coal seam are relatively high and the average values are greater than 20 μg/g. The contents of Se and Hg are at a high level while most other trace elements are at normal levels. (2) The cleanliness grade of the coal seam is mainly grade III–IV, which corresponds to a relatively good-medium coal cleanliness grade. However, some parts of the seam are at grade V (relatively poor coal cleanliness). (3) Coal of relatively good cleanliness grade (grade III) is distributed mainly in the regions corresponding to the Zhuji-Dingji-Gubei coal mines and in the eastern periphery of the Panji coal mine. Coal of medium cleanliness (grade IV) is distributed mainly in the regions of the Panji-Xiejiaji and Kouzidong coalmines. Relatively poor grade coal (grade V) is distributed in the southwest regions of the coalfield and the contents of Cr, As and Hg in coal collected from the relatively poor coal cleanliness regions often exceed the regulatory standards for the maximum concentration limits.

scholarly journals COSMIC COVARIANCE AND THE LOW QUADRUPOLE ANISOTROPY IN THE WMAP DATA

2008 ◽  
Vol 23 (17n20) ◽  
pp. 1489-1497 ◽  
Author(s):  
LUNG-YIH CHIANG ◽  
PAVEL D. NASELSKY ◽  
PETER COLES
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
A Priori ◽  
Gaussian Random Field ◽  
Minimum Variance ◽  
Microwave Background ◽  
Data Release ◽  
Intrinsic Correlation ◽  
Wmap Data ◽  
Cmb Temperature

Low quadrupole power in the cosmic microwave background (CMB) temperature anisotropies has been a puzzle since WMAP data release. In this talk I will demonstrate that the minimum variance optimization (MVO), a methodology used by many authors including the WMAP science team to separate the CMB from foreground contamination, serves not only to extract the CMB, but to subtract the “cosmic covariance”, an intrinsic correlation between the CMB and the foregrounds. Such subtraction induces low variance in the signal via MVO, which in turn propagates into the multipoles, causing a quadrupole deficit with more than 90% CL. As we do not know the CMB and the foregrounds a priori, and their correlation is subtracted by the MVO in any case, there is therefore an unknown error in the quadrupole power even before the cosmic variance interpretation. We combine the MVO and Monte Carlo simulations, assuming CMB is a Gaussian random field, and the estimated quadrupole power falls in [308.13, 401.97] μ K 2 (at 1 − σ level).

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