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Evolution individuality

Weak communal evolution Strong communal evolution Individual evolution... [Pg.222]

For the selection of descriptors, GA simulated evolution of a population. Each individual of the population represents a subset of descriptors and is defined by a chromosome of binary values. The chromosome has as many genes as there are possible descriptors (92 for the aromatic group, 119 for non-rigid aliphatic,... [Pg.527]

Human evolution has taken place close to sea level, and humans are physiologically adjusted to the absolute partial pressure of the oxygen at that point, namely 21.2 kPa (159.2 mm Hg), ie, 20.946% of 101.325 kPa (760 mm Hg). However, humans may become acclimatized to life and work at altitudes as high as 2500—4000 m. At the 3000-m level, the atmospheric pressure drops to 70 kPa (523 mm Hg) and the oxygen partial pressure to 14.61 kPa (110 mm Hg), only slightly above the 13.73 kPa (102.9 mm Hg) for the normal oxygen pressure in alveolar air. To compensate, the individual is forced to breathe much more rapidly to increase the ratio of new air to old in the lung mixture. [Pg.482]

Defining the requirements for a pilot-plant control system is often difficult because process plant experience for comparison and evaluation is commonly lacking and the design is frequentiy performed by personnel inexperienced in either instmmentation systems or pilot-plant operations. The isolated and often intermittent nature of pilot-plant operations also inhibits evolution and promotes individual unique installations. This compHcates the selection process. [Pg.42]

Deterministic air quaUty models describe in a fundamental manner the individual processes that affect the evolution of pollutant concentrations. These models are based on solving the atmospheric diffusion —reaction equation, which is in essence the conservation-of-mass principle for each pollutant species... [Pg.379]

Figure 7. 5. Time evolution of crystallographic texture [(0002) pole figures] along the axis of an explosively driven, hemispherical, titanium liner [66]. A high density of contours near the center of the circle indicate the c-axes of individual crystals are all normal to liner surface. Figure 7. 5. Time evolution of crystallographic texture [(0002) pole figures] along the axis of an explosively driven, hemispherical, titanium liner [66]. A high density of contours near the center of the circle indicate the c-axes of individual crystals are all normal to liner surface.
Servos gives a beautifully clear explanation of the subject-matter of physical chemistry, as Ostwald pursued it. Another excellent recent book on the evolution of physical chemistry, by Laidler (1993) is more guarded in its attempts at definition. He says that it can be defined as that part of chemistry that is done using the methods of physics, or that part of physics that is concerned with chemistry, i.e., with specific chemical substances , and goes on to say that it cannot be precisely defined, but that he can recognise it when he sees it Laidler s attempt at a definition is not entirely satisfactory, since Ostwald s objective was to get away from insights which were specific to individual substances and to attempt to establish laws which were general. [Pg.26]

Stephen Keith, a historian of science, has examined the development of this parepisteme (Keith 1998), complete with the stops and starts caused by fierce competition between individuals and the discouragement of some of them, while a shorter account of the evolution of crystal-growing skill can be found in the first... [Pg.160]

In the finite-difference appntach, the partial differential equation for the conduction of heat in solids is replaced by a set of algebraic equations of temperature differences between discrete points in the slab. Actually, the wall is divided into a number of individual layers, and for each, the energy conserva-tk>n equation is applied. This leads to a set of linear equations, which are explicitly or implicitly solved. This approach allows the calculation of the time evolution of temperatures in the wall, surface temperatures, and heat fluxes. The temporal and spatial resolution can be selected individually, although the computation time increa.ses linearly for high resolutions. The method easily can be expanded to the two- and three-dimensional cases by dividing the wall into individual elements rather than layers. [Pg.1067]

IFIGI3RE 11.34 Determination of the real evolution of the heat flux at the inside wall surface The temperature condition at the exterior surface is approximated by triangular pulses, and the heat flux response at the interior surface is determined by superposition of the heat flux responses of the individual pulses. [Pg.1068]

Contaminant concentrations Dispersal of airborne contaminants such as odors, fumes, smoke, VOCs, etc. transported by these airflows and transformed by a variety of processes including chemical and radiochemical transformation, adsorption, desorption to building materials, filtration, and deposition to surfaces evolution of contaminant concentrations in the individual zones air quality checks in terms of CO2 levels cross-contamination evaluation of zones air quality evaluations in relation to perception as well as health. Methods ate also applicable to smoke control design. [Pg.1082]

With given contaminant source and sink schedules and outdoor concentrations, concentration evolutions over time can be determined for the individual zones on the basis of the calculated airflow rate values per time step. Further postprocessing allows the determination of accumulated values such as air change rate or concentration histograms (see the later example) or inhaled dose values. [Pg.1083]

In a recent paper [11] this approach has been generalized to deal with reactions at surfaces, notably dissociation of molecules. A lattice gas model is employed for homonuclear molecules with both atoms and molecules present on the surface, also accounting for lateral interactions between all species. In a series of model calculations equilibrium properties, such as heats of adsorption, are discussed, and the role of dissociation disequilibrium on the time evolution of an adsorbate during temperature-programmed desorption is examined. This approach is adaptable to more complicated systems, provided the individual species remain in local equilibrium, allowing of course for dissociation and reaction disequilibria. [Pg.443]

Bohnenkamp and Engell and Caplan et have also reported rapid carbon loss from the steel during the initial stage of oxidation at higher temperatures (circa 850°C) followed by a much lower, or zero, loss of carbon later. Caplan et at. measured the COj evolution by infrared gas analysis and reported that the percentage of carbon loss from 0.1 %C, 0.4%C, 0.8%C and 1.2%C steels was overall very small and may be redistributed in the metal. There was no carbon loss detected at 700°C. The overall oxidation rates were all found to be parabolic at 850°C and less than the oxidation rate of pure Fe. In the Fe-C alloys the individual phases of FeO, FejO and... [Pg.974]

Chapter 8 describes a number of generalized CA models, including reversible CA, coupled-map lattices, quantum CA, reaction-diffusion models, immunologically motivated CA models, random Boolean networks, sandpile models (in the context of self-organized criticality), structurally dynamic CA (in which the temporal evolution of the value of individual sites of a lattice are dynamically linked to an evolving lattice structure), and simple CA models of combat. [Pg.19]

State transitions are therefore local in both space and time individual cells evolve iteratively according to a fixed, and usually deterministic, function of the current state of that cell and its neighboring cells. One iteration step of the dynamical evolution is achieved after the simultaneous application of the rule (p to each cell in the lattice C. [Pg.41]

The preceding section dealt with the statistical properties of the set of cell values in individual configurations. An alternative, and in some sense complementary, approach is to examine the statistical properties of the set of all possible configurations. Such a global view sets the stage for drawing comparisons between the evolution of CA and that of general dynamical systems. [Pg.75]

Figures 3.24 and 3.25, for example, show the probabilities for the 2 ° pos.sible configurations on an = 10 lattice obtained at time t = 10 for evolutions by rules R126 and R30 (both in class c3), respectively. The figures show that the evolution modifies the probabilities of states from initially being equally likely to distributions in which individual configurations can have widely differing final probabilities. The properties of the more probable states will then tend to dominate the statistical averages over the enseiiible. Figures 3.24 and 3.25, for example, show the probabilities for the 2 ° pos.sible configurations on an = 10 lattice obtained at time t = 10 for evolutions by rules R126 and R30 (both in class c3), respectively. The figures show that the evolution modifies the probabilities of states from initially being equally likely to distributions in which individual configurations can have widely differing final probabilities. The properties of the more probable states will then tend to dominate the statistical averages over the enseiiible.

See other pages where Evolution individuality is mentioned: [Pg.49]    [Pg.49]    [Pg.1487]    [Pg.1542]    [Pg.1985]    [Pg.2967]    [Pg.527]    [Pg.23]    [Pg.147]    [Pg.402]    [Pg.252]    [Pg.476]    [Pg.377]    [Pg.277]    [Pg.1875]    [Pg.66]    [Pg.30]    [Pg.78]    [Pg.43]    [Pg.362]    [Pg.366]    [Pg.409]    [Pg.5]    [Pg.321]    [Pg.309]    [Pg.310]    [Pg.11]    [Pg.81]    [Pg.87]    [Pg.253]    [Pg.443]    [Pg.581]   
See also in sourсe #XX -- [ Pg.215 ]




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