497 research outputs found
Network protocol scalability via a topological Kadanoff transformation
A natural hierarchical framework for network topology abstraction is
presented based on an analogy with the Kadanoff transformation and
renormalisation group in theoretical physics. Some properties of the
renormalisation group bear similarities to the scalability properties of
network routing protocols (interactions). Central to our abstraction are two
intimately connected and complementary path diversity units: simple cycles, and
cycle adjacencies. A recursive network abstraction procedure is presented,
together with an associated generic recursive routing protocol family that
offers many desirable features.Comment: 4 pages, 5 figures, PhysComNet 2008 workshop submissio
Temporal Correlations of Local Network Losses
We introduce a continuum model describing data losses in a single node of a
packet-switched network (like the Internet) which preserves the discrete nature
of the data loss process. {\em By construction}, the model has critical
behavior with a sharp transition from exponentially small to finite losses with
increasing data arrival rate. We show that such a model exhibits strong
fluctuations in the loss rate at the critical point and non-Markovian power-law
correlations in time, in spite of the Markovian character of the data arrival
process. The continuum model allows for rather general incoming data packet
distributions and can be naturally generalized to consider the buffer server
idleness statistics
The study of methods of preliminary cooling of fruits
The studies were aimed at scientific grounding of expedience of combination of preliminary cooling of apples, pears and plums and their processing by antioxidant compositions before the long storage and also at establishing of the optimal regimes and methods of this technological operation. The objects of studies were apple, pear and plums fruits of the different pomological species. As a result of studies was offered the combined method that provides preliminary cooling of apple fruits firstly by hydro-cooling in solutions of antioxidant compositions during 1 hour to the temperature in fruit center 8,5 °С, then additional cooling in AOC solutions during 1,5 hours to the temperature in fruit center 9 °С, additional cooling in chamber of intensive cooling during 50 minutes to the temperature in fruit center 1°С. For plum: hydro-cooling in AOC solutions during 40 minutes to the temperature in fruit center 9 °С, additional cooling in chamber of intensive cooling during 30 minutes to the temperature in fruit center 1°С. The use of such method of preliminary cooling provides the fast decrease of intensity of breath and thermal flux of fruits and essentially decreases the lost of their mass. It favors the prolongation of term of storage of fruit raw material with maximal preservation of quality and biological value. The received data and their scientific grounding give a possibility to recommend producers to use the offered method of preliminary cooling in production condition
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