Conservation long-term

For long term simulations, it turns out that the reproduction of the conservation properties is most important in order to ensure reliable results. 

Long term simulations require structurally stable integrators. Symplec-tic and symmetric methods nearly perfectly reproduce structural properties of the QCMD equations, as, for example, the conservation of the total energy. We introduced an explicit symplectic method for the QCMD model — the Pickaback scheme— and a symmetric method based on multiple time stepping. 

For long-term simulations, it generally proves advantageous to consider numerical integrators which pass the structural properties of the model onto the calculated solutions. Hence, a careful analysis of the conservation properties of QCMD model is required. A particularly relevant constant of motion of the QCMD model is the total energy of the system... 

Modem synthetic polymers are the subject of increasing research by conservation scientists. Not only does their frequent use in conservation treatments require a better understanding of their long term stabiUty, but also many objects, including those in collections of contemporary art and in history and technology museums, are made out of these new materials. 

Conservation. In an attempt to save paper, preventive conservation care deserves the highest priority, because it reduces the need for potentially hazardous, comphcated, and expensive treatments later (159—162). Problems which have a stmctural impact on long-term stabiUty of paper should be given a higher priority than problems which are merely cosmetic in nature. For example, infestation by insects, attracted by nutrients in paper, can cause irreparable loss of media and support. 

Unfortunately steroids merely suppress the inflammation while the underlying cause of the disease remains. Another serious concern about steroids is that of toxicity. The abmpt withdrawal of glucocorticoid steroids results in acute adrenal insufficiency. Long term use may induce osteoporosis, peptidic ulcers, the retention of fluid, or an increased susceptibiUty to infections. Because of these problems, steroids are rarely the first line of treatment for any inflammatory condition, and their use in rheumatoid arthritis begins after more conservative therapies have failed. 

The number of cancers over the next 70 years firom this exposure, was estimated using the conservative linear model to be 160 which should be compared with 27,000 cancers the evacuees will get from natural causes over 70 years. Thus, the long-term effect of the accident will be... 

Synthetic polymers are very important in conservation science because they are commonly used for the conservation and restoration of artworks. Consequently, their chemical characterization must be precise enough to well define their innocuousness for art objects and their long term stability. An example is given in the ToF-SIMS analysis of polymers... 

A maximum flexural stress of 9,500 psi is assumed for polycarbonate. This conservative stress value should account for degradation in ultraviolet stabilized polycarbonate exposed to long term solar exposure. While more research is required in this area, it is reasonable to expect at least a ten year useful life for ultraviolet stabilized polycarbonate. A Young s modulus of 345,000 psi and a Poisson s ratio of 0.38 are also assumed for polycarbonate. 

The conservatives Passive reaction, Most likely to behave Short or long term,... 

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