نتایج جستجو برای: power spectrum area fractal method

تعداد نتایج: 2694931  

Journal: :EAI Endorsed Trans. Complex Systems 2013
Matteo Convertino Filippo Simini Filippo Catani Igor Linkov Gregory A. Kiker

Patterns of animate and inanimate systems show remarkable similarities in their aggregation. One similarity is the double-Pareto distribution of the aggregate-size of system components. Different models have been developed to predict aggregates of system components. However, not many models have been developed to describe probabilistically the aggregate-size distribution of any system regardles...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه بیرجند - دانشکده علوم انسانی 1390

in solvo-hydrothermal method, xrd pattern was indicated presence of intermediate of ammonium octatmolybdate and ammonium tetramolybdate, which were changed to stble phase of ?-moo3 annealing. sem images were indicated nanoparticle with semispheical morphology and tem image was demonstrated nanoparticles with a diameter size of 25nm. also in impregnate method. the xrd pattern was shown high crys...

2007
MARK J. EMBRECHTS

There are several methods for estimating the fractal dimension of a time series of data such as the box counting method and the correlation method [DeGrauwe, Dewachter and EmbrechtS, 1993] [peitgen and Saupe, 1988]. The application of these methods are often demanding in computing time and require expert interaction for interpreting the calculated fractal dimension. Artificial neural nets (ANN)...

2012
M. J. Levin M. J. LEVIN

An asymptotic analysis is carried out for an approximate method of estimating the parameters of the power spectrum of a zero-mean stationary Gaussian random process from an observed realization of limited duration. Maximum likelihood estimates are obtained with the approximation that the coefficients of the Fourier series expansion of the realization are uncorrelated. This is equivalent to othe...

In this work, SiO2 –ZrO2 mixed oxides was prepared by the polymeric sol–gel route. The characterization of pore structure, which determines the permeation process of membrane, is of great importance. So far, most investigations have focused on such pore structure as specific surface area and pore size distribution, but the surface fractal, the important parameter reflecting the roughness of por...

1998
Lorenzo Galleani Letizia Lo Presti

This paper presents a method for the classification of nonlinear systems through the study of the free oscillations in the time-frequency plane, when the measured data are affected by fractal noise of the Wiener type. Nonconservative SDOF (Single Degree Of Freedom) oscillators described by a nonlinear second order differential equation are considered. The nonlinearity is due to a nonlinear func...

2003
H. W. ZHOU H. XIE

A direct determination of the fractal dimensions of a fracture surface is essential for a better understanding of its complete topographic characteristics. In this paper, a laser profilometer is employed to measure the topography of a rock’s fracture surface. With the use of the triangular prism surface area and projective covering methods, the resultant data set enables us to directly determin...

جهانگرد محمدی, , فایز رئیسی گهرویی, ,

Knowledge of the spatial dependency of soil properties, sensitive to grazing systems, is important from an ecosystem protection point of view. In the current study, geostatistical methods and fractal concepts have been used in order to characterize the impact of long-term grazing exclusion on the spatial variability of some soil chemical parameters including organic matter, total nitrogen, avai...

ژورنال: علوم آب و خاک 2004
جهانگرد محمدی, , فایز رئیسی گهرویی, ,

Knowledge of the spatial dependency of soil properties, sensitive to grazing systems, is important from an ecosystem protection point of view. In the current study, geostatistical methods and fractal concepts have been used in order to characterize the impact of long-term grazing exclusion on the spatial variability of some soil chemical parameters including organic matter, total nitrogen, avai...

2013
David A. Seekell Michael L. Pace Lars J. Tranvik Charles Verpoorter

[1] The abundance and size distribution of lakes is critical to assessing the role of lakes in regional and global biogeochemical processes. Lakes are fractal but do not always conform to the power law size-distribution typically associated with fractal geographical features. Here, we evaluate the fractal geometry of lakes with the goal of explaining apparently inconsistent observations of powe...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید