Results 261 to 270 of about 8,265,428 (297)

Density‐Dependent Natural Selection

Ecology, 1971
Density—dependent selective values illustrate the evolutionary effect of population—regulating processes that diminish an individual's probability of survival with increased crowding. The selective values, assumed to decrease as a linear function of density, lead in a mild environment to the evolution of phenotypes having a high carrying capacity, K ...
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The relation between density regulation and natural selection

Proceedings of the Royal Society of London. Series B - Biological Sciences, 1956
Abstract Darwin (1859) introduced the notion of natural selection by showing that if the density of a species is to remain steady, most of the individuals in each generation must die prematurely. Nicholson (1954) has analyzed the factors determining the density of a species in great detail. Haldane (1953) did so more summarily.
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Density and Viscosity Measurements of Natural Solutions

Chemistry and Ecology, 1986
Abstract Utilizing sophisticated equipment, densimetric and viscosimetric measurements were carried out on samples of ground-waters of Apulia. Experimental data, utilized to check if simple equations can evaluate the density and the viscosity of multicomponent solutions, confirm the validity of the hypothesis.
POLEMIO M., PROVENZANO M. R., BUFO S., SACCO, ANTONIO   +3 more
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Kernel Estimators of Density in Spaces of an Arbitrary Nature

Journal of Mathematical Sciences, 2001
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Prediction of the density for natural gas and liquefied natural gas mixtures

AIChE Journal, 2001
AbstractExperimental liquid densities and compressibility factors of natural gas and liquefied natural gas mixtures were reproduced using an analytical equation of state, based on the statistical‐mechanical perturbation theory of Weeks, Chandler and Andersen.
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Density of Liquefied Natural Gas Components

1978
When measuring cargoes of liquefied natural gas (LNG), knowledge is required of its composition, volume, temperature, and density. It was decided in 1968 to look into the problem of determining LNG density characteristics. Rather than developing a direct-reading densimeter, work was directed toward determining density as a function of composition and ...
J. E. Orrit, J. M. Laupretre
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Density of cellulose fibers. III. Density and refractivity of natural fibers and rayon

Journal of Polymer Science, 1946
AbstractA micromethod is described for density determinations of artificial cellulose fibers by the floating method, in carbon tetrachloride in a dry and air‐free atmosphere, permitting an accuracy of one part per thousand. The density is derived from the temperature at which the samples neither sink nor float. This temperature varies, with the kind of
P. H. Hermans, J. J. Hermans, D. Vermaas
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Natural densities of Markov transition probabilities

Probability Theory and Related Fields, 1986
Let \((P_ t)\), \((P^*\!_ t)\) be two measurable submarkovian semigroups on a measurable space E which are absolutely continuous and in duality with respect to a \(\sigma\)-finite measure \(\mu\). Then it is shown that there exists a unique measurable function \(p: (0,\infty)\times E\times E\to {\bar {\mathbb{R}}}_+\) satisfying \[ (i)\quad P_ tf(x ...
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On Density of Pairs of Natural Numbers

2015
Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 zostało dofinansowane ze środków MNiSW w ramach działalności upowszechniającej naukę.
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Chebyshev's Inequality and Natural Density

The American Mathematical Monthly, 1989
Curtis N. Cooper, Robert E. Kennedy
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