195 research outputs found
Hand tool permits shrink sizing of assembled tubing
Portable tool sizes tubing ends without disassembling the tubing installation. The shrink sizing tool is clamped to the tubing and operated by a ratchet wrench. A gear train forces the tubing end against an appropriate die or mandrel to effect the sizing
Effective Monte Carlo simulation on System-V massively parallel associative string processing architecture
We show that the latest version of massively parallel processing associative
string processing architecture (System-V) is applicable for fast Monte Carlo
simulation if an effective on-processor random number generator is implemented.
Our lagged Fibonacci generator can produce random numbers on a processor
string of 12K PE-s. The time dependent Monte Carlo algorithm of the
one-dimensional non-equilibrium kinetic Ising model performs 80 faster than the
corresponding serial algorithm on a 300 MHz UltraSparc.Comment: 8 pages, 9 color ps figures embedde
Literary families and ancient hermeneutics : Acts and Grego-Roman contemporary historiography
https://place.asburyseminary.edu/ecommonsatsdissertations/2278/thumbnail.jp
Cluster approximation solution of a two species annihilation model
A two species reaction-diffusion model, in which particles diffuse on a
one-dimensional lattice and annihilate when meeting each other, has been
investigated. Mean field equations for general choice of reaction rates have
been solved exactly. Cluster mean field approximation of the model is also
studied. It is shown that, the general form of large time behavior of one- and
two-point functions of the number operators, are determined by the diffusion
rates of the two type of species, and is independent of annihilation rates.Comment: 9 pages, 7 figure
Organisational Learning and Learning Organisations: A Literature Review
The survival of any organisation, particularly one that is profit oriented, depends to a large extent, on how well it can accept and adapt to environmental changes, and do better in terms of its operations. This conceptual paper reviewed some extant literatures on organisational learning and learning organisations with a view to answering the following question: First, how do you identify a learning organisation when you see one? Secondly, what is the conceptual difference between organisational learning and learning organisation? Thirdly, what are those impediments that deprive organisation from becoming a learning organisation? Fourthly, what benefits do organisations derive from being a learning organisation? Furthermore, it attempted to pinpoint some examples of learning organisations in Nigeria and USA. The contributions of the different approaches to the study of organisation learning and learning organisation are analyzed, and some areas are suggested where the transfer of analytical concepts may improve understanding. Accordingly, this paper supports the proposition that organisation learning culture has direct influence on organisational innovativeness, which is directly tied to long-term organisational success. It is recommended, therefore, that any organisation that wants to remain competitive should focus on becoming a learning organisation. The authors further recommends that more empirical research is required in the construct to investigate whether there are indeed organisations that can truly be called learning organisations or the construct is just a misnomer. Keywords: learning organisation, organisational leaning, knowledge transfer, competitive advantag
Urban segregation with cheap and expensive residences
In this paper we study urban segregation of two different communities A and
B, poor and rich, distributed randomly on finite samples, to check cheap and
expensive residences. For this purpose we avoid the complications of the
Schelling model which are not necessary and instead we use the Ising model on
500 x 500 square lattice, which give similar results, with random magnetic
field at lower and higher temperatures (kT/J = 2.0, 99.0) in finite times equal
to 40, 400, 4000 and 40,000. This random-field Ising magnet is a suitable
model, where each site of the square lattice carries a magnetic field h which
is randomly up (expensive) or down (cheap). The resulting addition to the
energy prefers up spins on the expensive and down spins on the cheap sites. Our
simulations were carried out using a 50-lines FORTRAN program. We present at a
lower temperature (2.0) a time series of pictures, separating growing from
non-growing domains. A small random field (h = +- 0.1) allows for large
domains, while a large random field (h = +- 0.9) allows only small clusters. At
higher temperature (99.0) we could not obtain growing domains.Comment: 11 pages, large figures, shortened version will be prepared for IJMP
Non-equilibrium phase transitions in one-dimensional kinetic Ising models
A family of nonequilibrium kinetic Ising models, introduced earlier, evolving
under the competing effect of spin flips at {\it zero temperature} and nearest
neighbour random spin exchanges is further investigated here. By increasing the
range of spin exchanges and/or their strength the nature of the phase
transition 'Ising-to-active' becomes of (dynamic) mean-field type and a first
order tricitical point is located at the Glauber () limit.
Corrections to mean-field theory are evaluated up to sixth order in a cluster
approximation and found to give good results concerning the phase boundary and
the critical exponent of the order parameter which is obtained as
.Comment: 15 pages, revtex file, figures available at request from
[email protected] in postscript format, submitted to J.Phys.
Slow Logarithmic Decay of Magnetization in the Zero Temperature Dynamics of an Ising Spin Chain: Analogy to Granular Compaction
We study the zero temperature coarsening dynamics in an Ising chain in
presence of a dynamically induced field that favors locally the `-' phase
compared to the `+' phase. At late times, while the `+' domains still coarsen
as , the `-' domains coarsen slightly faster as . As
a result, at late times, the magnetization decays slowly as, . We establish this behavior both analytically within an
independent interval approximation (IIA) and numerically. In the zero volume
fraction limit of the `+' phase, we argue that the IIA becomes asymptotically
exact. Our model can be alternately viewed as a simple Ising model for granular
compaction. At late times in our model, the system decays into a fully compact
state (where all spins are `-') in a slow logarithmic manner , a fact that has been observed in recent experiments on granular systems.Comment: 4 pages Revtex, 3 eps figures, supersedes cond-mat/000221
Multispecies reaction-diffusion systems
Multispecies reaction-diffusion systems, for which the time evolution
equation of correlation functions become a closed set, are considered. A formal
solution for the average densities is found. Some special interactions and the
exact time dependence of the average densities in these cases are also studied.
For the general case, the large time behaviour of the average densities has
also been obtained.Comment: LaTeX file, 15 pages, to appear in Phys. Rev.
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