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101.
Artur Manuel Ribeiro dos Santos Caldas de Matos Reiji Suzuki Takaya Arita 《Artificial Life and Robotics》2007,11(2):175-182
Recent studies in evolutionary computation have focused on using developmental processes together with genetic algorithms
in order to achieve more complex designs. Although several models have been proposed, their growth dynamics, and their interactions
with evolutionary algorithms are still poorly understood. One particularly neglected concept in artificial developmental systems
is heterochrony: how evolution affects development by changing the timing and rate of developmental events. In this article we attempt to
address this issue by analyzing heterochronic changes in a well-known artificial developmental model, the cellular encoding
model, by using a previously developed heterochrony framework. We have conducted experiments by evolving networks to solve
a Boolean problem, and analyzed heterochronic changes in both successful and unsuccessful runs. Our findings show that owing
to its properties, the cellular encoding model strongly affects the developmental dynamics and the heterochronic changes that
occur during evolution. Our experiments also show that hypermorphic changes (a kind of heterochronic occurrence) lead to greater
evolvability in successful runs. 相似文献
102.
Hydrodynamische Einlauflänge und Widerstandsgesetz von reibungsmindernden kationschen Tensidlösungen
Dipl.-Ing. Hans-Heinrich Kleuker cand. ing. Anke Laurenzis Dr.-Ing. Wilhelm Althaus Dr.-Ing. Artur Steiff Prof. Dr.-Ing. Paul-Michael Weinspach 《Forschung im Ingenieurwesen》1993,59(1-2):8-18
Zusammenfassung Durch Zugabe geeigneter Tensidsysteme in Wasser kann der Str?mungsdruckverlust in geraden Rohren erheblich gesenkt werden.
Die diesem Effekt zugrunde liegenden Mechanismen wurden in früheren Arbeiten eingehend diskutiert. In dieser Arbeit werden
neue Ergebnisse vorgestellt, die sowohl die Bestimmung der hydrodynamischen Einlaufl?nge als auch die Ermittlung der Widerstandsbeiwerte
im ausgebildeten Str?mungszustand erm?glichen. Für den Bereich der ausgebildeten Rohrstr?mung wird eine neue Berechnungsgleichung
vorgeschlagen. Durch Erweiterung der bisherigen Modellvorstellungen ergibt sich ein Widerstandsgesetz für den gesamten Wirkungsbereich
des Tensids. Die Ergebnisse stützen sich auf Untersuchungen mit zwei verschiedenen Additivsystemen, bei denen die Parameter
Str?mungsgeschwindigkeit, Temperatur und Einsatzkonzentration variiert wurden. 相似文献
103.
104.
In three-phase systems, where the liquid constitutes the continuous phase, solid is the catalyst and gas represents the dispersed phase, there are decisive criteria which have to be observed in reactor design. These are e.g. the interfacial area per unit volume between gas and liquid, the volumetric mass transfer coefficient and the mass transfer coefficient. The basic aim of the present work was therefore the investigation of these parameters in relation to the main influencing parameters. Process parameters stirrer speed and superficial gas velocity were varied as well as the physical properties such as liquid viscosity, solids concentration, particle diameter and a geometrical parameter, i.e. reactor diameter. The sulphite method was employed for the determination of these values. The test results confirmed the known relationships of power consumption and superficial gas velocity. An increase in the liquid viscosity leads to a decrease in all the tested values. In most cases, suspended solid particles lead to a lowering of the test values. The influence of the tank diameter on the plots of the test values against specific power consumption turned out to be invariant so that a scale-up of geometrically similar systems can be carried out at constant power consumption, superficial gas velocity and liquid viscosity. 相似文献
105.
106.
107.
108.
Z Bartkowiak 《Canadian Metallurgical Quarterly》1995,49(3):270-276
The author presents data on the biological casualties and consequences of tobacco-smoking. Smoking is the most dangerous addiction in the scale of the world and in Poland. It causes numerous premature decrease and tobacco-dependent sickness. The author characterises the spread of this addiction in Poland concentrating on the problem of the passive smoking harmfulness. Non-smokers, children and youth, embryo and foetus during the pregnancy are exposed to the passive smoking. The experimental examinations of animals and the analysis of the lateral stream of the tobacco smoke confirm not the least, but rather the greater damage of the passive smoking than the active one. The mechanisms of acting of the tobacco smoke on the passive smokers' body and the health consequences are discussed. The manners, means and activities that are useful for the health protection of non-smokers against the tobacco smoke and the ways of the smoking prevention are described. 相似文献
109.
110.
Kaczyński Łukasz K. Cais-Sokolińska Dorota Szwengiel Artur 《Food science and biotechnology》2019,28(5):1529-1534
Food Science and Biotechnology - The aim of this work was the analysis of galactooligosaccharides (GOS) formation in a model mixture of goat’s milk and its permeate from microfiltration and... 相似文献