257,656 research outputs found
Competing contact processes in the Watts-Strogatz network
We investigate two competing contact processes on a set of Watts--Strogatz
networks with the clustering coefficient tuned by rewiring. The base for
network construction is one-dimensional chain of sites, where each site
is directly linked to nodes labelled as and . So initially,
each node has the same degree . The periodic boundary conditions are
assumed as well.
For each node the links to sites and are rewired to two
randomly selected nodes so far not-connected to node . An increase of the
rewiring probability influences the nodes degree distribution and the
network clusterization coefficient . For given values of rewiring
probability the set of networks is generated.
The network's nodes are decorated with spin-like variables .
During simulation each node having a -site in its neighbourhood converts
this neighbour from to state. Conversely, a node in state having at
least one neighbour also in state -state converts all nearest-neighbours of
this pair into -state. The latter is realized with probability .
We plot the dependence of the nodes final density on initial
nodes fraction . Then, we construct the surface of the unstable
fixed points in space. The system evolves more often
toward for points situated above this
surface while starting simulation with parameters
situated below this surface leads system to . The points on this
surface correspond to such value of initial fraction of nodes (for
fixed values and ) for which their final density is
.Comment: 5 pages, 5 figure
The human, primate and rabbit ultraviolet action spectra
A 5000 watt xenon-mercury high pressure lamp was used to produce a continuous ultraviolet spectrum. Human and animal exposures were made to establish the photokeratitis threshold and abiotic action spectrum. The lower limit of the abiotic action spectrum was 220 nm while the upper limit was 310 nm. The radiant exposure threshold at 270 nm was 0.005 watts/sq cm for the rabbit, 0.004 watts/sq cm for the primate, and 0.004 watts/ sq cm for the human. The rabbit curve was bi-peaked with minimums at 220 nm, 240 nm and 270 nm. The primate curve was tri-peaked with minimums at 220 nm, 240 nm and 270 nm. The human data showed a rather shallow curve with a minimum at 270 nm. Formulas and calculations are given to predict minimum exposure times for ocular damage to man in outer space, to establish valid safety criteria, and to establish protective design criteria
byron C. Watts v. Ardith D. Watts : Respondent\u27s Brief
Appeal from the Judgment of the Third District Court in and for Salt Lake County, Utah the Honorable D. Frank Wilkins, Judg
D-branes, Orientifolds and K-theory
The complete D-brane spectrum in ZZ[squared] orientifolds is computed. Stable non-BPS D-branes with both integral and torsion charges are found. The relation to K-theory is discussed and a new K-theory relevant to orientifolds is suggested
byron C. Watts v. Ardith D. Watts : Appellant\u27s Brief
Appeal from the Judgment of the Third District Court in and for Salt Lake County, Utah the Honorable D. Frank Wilkins, Judg
Order-disorder phase transition in a cliquey social network
We investigate the network model of community by Watts, Dodds and Newman (D.
J. Watts et al., Science 296 (2002) 1302) as a hierarchy of groups, each of 5
individuals. A homophily parameter controls the probability
proportional to of selection of neighbours against distance
. The network nodes are endowed with spin-like variables , with
Ising interaction . The Glauber dynamics is used to investigate the
order-disorder transition. The transition temperature is close to 3.8 for
and it falls down to zero above this value. The result provides
a mathematical illustration of the social ability to a collective action {\it
via} weak ties, as discussed by Granovetter in 1973.Comment: 10 pages, 7 figure
Hermetic-coaxial package design for microwave transistors
Semiconductor package has been developed for high power semiconductor devices that operate in the GHz-frequency range at several watts. Package includes stud, insulating ring, electrically conductive washer, insulating washer, braze ring, and cap. It is mechanically strong and can be used with variety of circuits
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