We can view the flow of energy from sun to earth and back to outer space as constituting a great natural open system. In the broadest sense, an open system is any organized configuration of matter open to the inflow or outflow of energy or matter, or both. The life layer, man's environment on earth, can be regarded as an open system with arbitrary boundaries-one in the atmosphere above and another lying at the base of a shallow layer of soil or water. It is through the upper boundary that the open system of the life layer has its input and output of energy.
Within the life layer energy moves in many complex pathways. These movements of energy require the presence of matter, both to transport energy from place to place and to store it temporarily. Air and water, as highly mobile fluids, are the principal transporters of energy. Solid earth materials, such as soil, rock, and organic compounds along with air and water, provide for storage of energy within the open system. Placing energy in storage requires that it be transformed. Thus incoming solar energy in the radiant form goes into storage as sensible heat. In this form the energy may be transported by moving air or water, or it may be further transformed into latent energy.
An essential principle in the operation of open systems is that they tend to attain a dynamic equilibrium or steady state, in which rate of input of energy and matter equals rate of output, while the quantity of stored energy and matter within the system remains constant. In the case of the total global system of atmosphere, hydrosphere, and lithosphere only energy enters and leaves the system. Matter remains within the system boundary where it is forced to run repeatedly through flow cycles. Matter is thus recycled within the system. We can conclude that with respect to matter only, the global system is closed, rather than open. Energy, on the other hand, is cycled within the system and also enters and leaves the system.
Locals hypothesize that the legacy of Italian blood and culture in Cologne, colonized by the Romans more than 1500 years ago, makes the people more jovial and lighthearted. Cologne is the largest city on the Rhine.
Kolsch is not only the dialect spoken here but, also the name of their own top-fermented beer. There are more than 4,000 pubs, restaurant's and brewery taverns in Cologne.
Unlike many of the world's large cities, Cologne, with a population of over a million, gets better every day, there are more things to do and see, more new and innovative buildings... more
Travel is an opportunity to learn, whether geography, languages, history or other subjects.
Cologne is situated on the beautiful Rhine River.