9,595,559 research outputs found
Chance, Choice, and Consciousness: The Role of Mind in the Quantum Brain
Contemporary quantum mechanical description of nature involves two processes.
The first is a dynamical process governed by the equations of local quantum
field theory. This process is local and deterministic, but it generates a
structure that is not compatible with observed reality. A second process is
therefore invoked. This second process somehow analyzes the structure generated
by the first process into a collection of possible observable realities, and
selects one of these as the actually appearing reality. This selection process
is not well understood. It is necessarily nonlocal and, according to orthodox
thinking, is governed by an irreducible element of chance. The occurrence of
this irreducible element of chance means that the theory is not naturalistic:
the dynamics is controlled in part by something that is not part of the
physical universe. The present work describes a quantum mechanical model of
brain dynamics in which the quantum selection process is a causal process
governed not by pure chance but rather by a mathematically specified nonlocal
physical process identifiable as the conscious process.Comment: 27 pages, no figures, latexed, uses math_macros.tex that can be found
on Archive, full postscript available from
http://theor1.lbl.gov/www/theorygroup/papers/37944.p
On Practical Verification of Processes
The integration of a formal process theory with a practically usable notation is not straightforward, but it is necessary for practical verification of process specifications. Given such an intermediate language, a verification process that gives useful feedback is not trivial either: Model checkers are not powerful enough to deal with object models, and theorem provers provide insu#cient feedback and are not certain to find a proof
Implementation of critical success factors in construction research and development process
Construction research and development (R&D) process has a number of issues that affect its success. These issues imply that Critical Success Factors (CSFs) of construction R&D process are not properly addressed. Not knowing CSFs could lead to not implementing them and not paying proper attention for them. The study investigates CSFs of construction R&D process and their implementation/consideration during the R&D process. A comprehensive literature review was used first to develop construction R&D process. CSFs and their implementation/consideration were evaluated by a questionnaire survey. Construction R&D process was derived with four phases namely Initiation, Conceptualizing, Development and Launch and Management activities that support coordination and resourcing of R&D process. Study revealed that, as a whole there is a gap between the importance of success factors against their implementation/consideration as majority of CSFs are not properly implemented compared to the importance attached to them.
Keywords: Construction R&D process, Critical success factors, Implementation, Consideratio
Poisson splitting by factors
Given a homogeneous Poisson process on with intensity
, we prove that it is possible to partition the points into two sets,
as a deterministic function of the process, and in an isometry-equivariant way,
so that each set of points forms a homogeneous Poisson process, with any given
pair of intensities summing to . In particular, this answers a
question of Ball [Electron. Commun. Probab. 10 (2005) 60--69], who proved that
in , the Poisson points may be similarly partitioned (via a
translation-equivariant function) so that one set forms a Poisson process of
lower intensity, and asked whether the same is possible for all . We do not
know whether it is possible similarly to add points (again chosen as a
deterministic function of a Poisson process) to obtain a Poisson process of
higher intensity, but we prove that this is not possible under an additional
finitariness condition.Comment: Published in at http://dx.doi.org/10.1214/11-AOP651 the Annals of
Probability (http://www.imstat.org/aop/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Limiting conditional distributions for birth-death processes
In a recent paper one of us identified all of the quasi-stationary distributions for a non-explosive, evanescent birth-death process for which absorption is certain, and established conditions for the existence of the corresponding limiting conditional distributions. Our purpose is to extend these results in a number of directions. We shall consider separately two cases depending on whether or not the process is evanescent. In the former case we shall relax the condition that absorption is certain. Furthermore, we shall allow for the possibility that the minimal process might be explosive, so that the transition rates alone will not necessarily determine the birth-death process uniquely. Although we shall be concerned mainly with the minimal process, our most general results hold for any birth-death process whose transition probabilities satisfy both the backward and the forward Kolmogorov differential equations
Complete convergence theorem for a two level contact process
We study a two-level contact process. We think of fleas living on a species
of animals. The animals are a supercritical contact process in .
The contact process acts as the random environment for the fleas. The fleas do
not affect the animals, give birth at rate when they are living on a host
animal, and die at rate when they do not have a host animal. The main
result is that if the contact process is supercritical and the fleas survive
with a positive probability then the complete convergence theorem holds. This
is done using a block construction, so as a corollary we conclude that the
fleas die out at their critical value
A criterion for separating process calculi
We introduce a new criterion, replacement freeness, to discern the relative
expressiveness of process calculi. Intuitively, a calculus is strongly
replacement free if replacing, within an enclosing context, a process that
cannot perform any visible action by an arbitrary process never inhibits the
capability of the resulting process to perform a visible action. We prove that
there exists no compositional and interaction sensitive encoding of a not
strongly replacement free calculus into any strongly replacement free one. We
then define a weaker version of replacement freeness, by only considering
replacement of closed processes, and prove that, if we additionally require the
encoding to preserve name independence, it is not even possible to encode a non
replacement free calculus into a weakly replacement free one. As a consequence
of our encodability results, we get that many calculi equipped with priority
are not replacement free and hence are not encodable into mainstream calculi
like CCS and pi-calculus, that instead are strongly replacement free. We also
prove that variants of pi-calculus with match among names, pattern matching or
polyadic synchronization are only weakly replacement free, hence they are
separated both from process calculi with priority and from mainstream calculi.Comment: In Proceedings EXPRESS'10, arXiv:1011.601
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