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The Temporal Variability of Densities: Back to Basics
Oikos, 1995We suggest that an index of the temporal variability of abundances should measure proportional change. SD (log[X]) seems to provide a general and interpretable statistic. However, when based on raw counts, a variability measure incorporates sampling error as well as the variability of the underlying densities.
Brian H. McArdle, Kevin J. Gaston
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Linfo – a visual basic program for lineament density, frequency and intersection density analysis
Earth Science Informatics, 2013This paper describes the development of visual basic program called ‘Linfo’ which can be used for calculation of spatial properties (orientation, length, density, frequency and intersection density) of lineaments. The program allows the user to analyze the orientation of lineaments easily and shows the results in the form of rose diagram.
A. C. Dinesh +2 more
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Predicting ash basicity from its density
Coke and Chemistry, 2010Physical determination of the chemical composition and actual density of the ash in coal and coal batch reveals that they are statistically related, as confirmed by high values of the multiple-correlation and determination coefficients. The proposed method of determining the actual density of the ash in coal and batch permits significantly more rapid ...
D. V. Miroshnichenko, M. B. Golovko
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Basic principles of electron density fluctuations in a plasma
Plasma Physics, 1977The collective fluctuation spectrum of the electron density in a plasma is calculated by a method which does not utilize a specific kinetic equation, and relies only on the following three very general principles: the linear response of a plasma to a weak electric field, the Nyquist theorem, and the principle of causality in the form of the Hilbert ...
O Theimer, W J Hicks, Y K Behl
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Low-Density Limit: The Basic Idea
2002In this chapter we consider the low-density limit and the associated equations, including the Boltzmann equation. Here we limit ourselves to a quick outline of the main ideas underlying the emergence of the number process in the stochastic limit and its connection with the 2-particle scattering operator.
Luigi Accardi +2 more
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Basic Concepts of Density Gradient Ultracentrifugation
2018This chapter reviews the development of centrifugal equipment and its achievements in various fields, especially in the field of life sciences. Based on the development of the equipment, centrifugal technology also plays a very crucial role in scientific research.
Jindi Wang, Jun Ma, Xuemei Wen
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Basic Density-Functional Theory an Overview
Physica Scripta, 2004In these notes I have given a personally flavored exposeof static density- functional theory (DFT). I have started from standard many-body physics at a very elementary level and then gradually introduced the basic concepts of DFT. Successively more advanced topics are added and at the end I even discuss a few not yet published theories.
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The Analysis of Electron Densities: From Basics to Emergent Applications
Chemical ReviewsThe electron density determines all properties of a system of nuclei and electrons. It is both computable and observable. Its topology allows gaining insight into the mechanisms of bonding and other phenomena in a way that is complementary to and beyond that available from the molecular orbital picture and the formal oxidation state (FOS) formalism ...
Daniel Koch +7 more
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Isotonic estimators of monotone densities and distribution functions: basic facts
Statistica Neerlandica, 1993We present short proofs of some basic results from isotonic regression theory. A straightforward argument is given to show that the left continuous version of the concave majorant of the empirical distribution function maximizes the likelihood function f↦f(X,)…f(Xn) within the class of non‐increasing densities.
Groeneboom, P., Lopuhaä, H. P.
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Simulation of lipid peroxidation in low density lipoprotein by a basic “skeleton” of reactions
Atherosclerosis, 1995A minimal kinetic model describing lipid peroxidation in low-density lipoprotein (LDL) has been set up. Models have been calculated by numeric integration of the differential equations describing this system consisting of seven reactions and eleven reactants in a single compartment.
P M, Abuja, H, Esterbauer
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