The estimation of the statistics of buffer overflows in networks of queues is inherently costly, simply because of the rarity of these events. This paper presents two eztensions to the known theory for finding optimal transformations for simulating such networks. The first is a direct proof of the asymptotic (as buffer size becomes large) optimality of ezchanging the arrival and service rates i...

We investigate the selective forces that promote the emergence of modularity in nature. We demonstrate the spontaneous emergence of modularity in a population of individuals that evolve in a changing environment. We show that the level of modularity correlates with the rapidity and severity of environmental change. The modularity arises as a synergistic response to the noise in the environment ...

2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd) is a by-product o f t he trichlorophenol (herbicide) production and is also produced through a variety of combustion processes. it appears that tcdd is a ubiquitous chemical, particularly in industrialised countries, and the liver is the target organ of its toxicity. the prominent hepatotoxic effect of tcdd is progressive centrilobular necrosis. the is...

Modern reorder buffers (ROBs) were conceived to improve processor performance by allowing instruction execution out of the original program order and run ahead of sequential instruction code exploiting existing instruction level parallelism (ILP). The ROB is a functional structure of a processor execution engine that supports speculative execution, physical register recycling, and precise excep...