Principle of nature

Convective heat transfer is classified as forced convection and natural (or free) convection. The former results from the forced flow of fluid caused by an external means such as a pump, fan, blower, agitator, mixer, etc. In the natural convection, flow is caused by density difference resulting from a temperature gradient within the fluid. An example of the principle of natural convection is illustrated by a heated vertical plate in quiescent air. 

Controlled Airflow through an Envelope Principles of Natural Ventilation 587... 

Newton, I. (1934). Sir Isaac Newton s Mathematical Principles of Natural Philosophy and His System of the World, tr. A. Motte, rev. F. Cajon. Berkeley University of California Press. 

BRE Digest 210, Principles of Natural Ventilation (B. B. Daly) (February 1978). 

The relationship between entropy change and spontaneity can be expressed through a basic principle of nature known as the second law of thermodynamics. One way to state this law is to say that in a spontaneous process, there is a net increase in entropy, taking into account both system and surroundings. That is,... 

Webster, Charles. Water as the ultimate principle of Nature the background to Boyle s Sceptical Chymist. Ambix 33 (1966) 96-107. 

Eigen, M. and Schuster, P. (1979), The Hypercycle. A Principle of Natural Self Organization, Springer, Berlin. 

Here, past events help to explain current events via implicit principles of natural selection. Such ultimate explanations have been famously criticized as just-so stories, too easy to frame and too difficult to test (Gould and Lewontin, 1979). There is certainly something to this charge. Just because available data or even experience shows that eyespots are widespread does not guarantee that they are adaptive now. Even if they are adaptive now, this is by itself insufficient grounds to claim they were selected because they were the best available adaptation for camouflage, as opposed to some other function, or for that matter that they were not selected at all but... 

Doyle L, Deeg H-J, Brown TM (2000) Scientific American, September Dyson F (1985) Origins of Life, Cambridge University Press Ehrenfreund P, Rasmussen S, Cleaves J, Chen L (2006) Astrobiology 6 490 Eigen M, Winkler R (1993) The Laws of the Game How The Principles of Nature Govern Chance, Princeton University Press... 

In 1687, Newton summarized his discoveries in terrestrial and celestial mechanics in his Philosophiae naturalis principia mathematica (Mathematical Principles of Natural Philosophy), one of the greatest milestones in the history of science. In this work he showed how his (45) principle of universal gravitation provided an explanation both of falling bodies on the earth and of the motions of planets, comets, and other bodies in the heavens. The first part of the Principia, devoted to dynamics, includes Newton s three laws of motion the second part to fluid motion and other topics and the third part to the system of the (50) world, in which, among other things, he provides an explanation of Kepler s laws of planetary motion. 

Forrest, S. Genetic algorithms principles of natural selection applied to computation. Science 1993, 261,... 

Matsuda H, Nishida N, Yoshikawa M. (2002) Antidiabetic principles of natural medicines. V. Aldose reductase inhibitors from Myrcia multiflora DC. (2) structures of Myrciacitrins IB, IV, and V. Chem PharmBull 50 429 31. 

Yoshikawa M, Shimada H, Nishida N, Li Y, Toguchida I, Yamahara J, Matsuda H. (1998) Antidiabetic principles of natural medicines. II. Aldose reductase and a-glucosidase inhibitors from Brazilian natural medicine, the leaves of Myrcia multiflora DC. (Myrtacae) Structures of myrciacitrins I and II and myrciaphenones A and B. Chem Pharm Bull 46 113-119. 

The Hypercycle a Principle of Natural Self-Organization. Springer Verlag. 

Charles Webster, Water as the Ultimate Principle of Nature The Background to... 

A number of most important discoveries were made, about this time, by the chemists of Britain, France, and Sweden, relating to the constituent parts of principles of natural substances. New objects have been discovered, which required new names and some of the substances already known, which had formerly been considered as simple, and perhaps elementary, were now found to be compounded while others, formerly held as compounds, were now found to be more simple than the substances of which they had been thought to be compounded. ... 

Eigen, M. and Winkler, R. (1983). Laws of the Game. How the Principles of Nature Govern Chance . Penguin Books, London. 

The question of determinateness presents itself as follows Let the initial (t = 0) values of all the macroscopically independent macroscopic variables be given the equations of macroscopic physics (thermal and hydro-dynamic equations, etc.) show that these variables evolve deterministically with t 0. Yet there are infinitely many different probability densities ( ")t = 0 which have the moments, etc., coinciding with the set of given initial macroscopic values. Each evolves (by Liouville s equation) differently, and hence may induce a different set of macroscopic expected values at / > 0. By what principle of natural selection is the class of probability densities so restricted as to restore macroscopic determinacy ... 

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